diff options
Diffstat (limited to 'security')
48 files changed, 3151 insertions, 1522 deletions
diff --git a/security/Makefile b/security/Makefile index c26c81e..a5918e0 100644 --- a/security/Makefile +++ b/security/Makefile @@ -16,7 +16,6 @@ obj-$(CONFIG_MMU) += min_addr.o # Object file lists obj-$(CONFIG_SECURITY) += security.o capability.o obj-$(CONFIG_SECURITYFS) += inode.o -# Must precede capability.o in order to stack properly. obj-$(CONFIG_SECURITY_SELINUX) += selinux/built-in.o obj-$(CONFIG_SECURITY_SMACK) += smack/built-in.o obj-$(CONFIG_AUDIT) += lsm_audit.o diff --git a/security/apparmor/Kconfig b/security/apparmor/Kconfig index 9b9013b..d49c539 100644 --- a/security/apparmor/Kconfig +++ b/security/apparmor/Kconfig @@ -29,3 +29,15 @@ config SECURITY_APPARMOR_BOOTPARAM_VALUE boot. If you are unsure how to answer this question, answer 1. + +config SECURITY_APPARMOR_HASH + bool "SHA1 hash of loaded profiles" + depends on SECURITY_APPARMOR + depends on CRYPTO + select CRYPTO_SHA1 + default y + + help + This option selects whether sha1 hashing is done against loaded + profiles and exported for inspection to user space via the apparmor + filesystem. diff --git a/security/apparmor/Makefile b/security/apparmor/Makefile index 5706b74..d693df8 100644 --- a/security/apparmor/Makefile +++ b/security/apparmor/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_SECURITY_APPARMOR) += apparmor.o apparmor-y := apparmorfs.o audit.o capability.o context.o ipc.o lib.o match.o \ path.o domain.o policy.o policy_unpack.o procattr.o lsm.o \ resource.o sid.o file.o +apparmor-$(CONFIG_SECURITY_APPARMOR_HASH) += crypto.o clean-files := capability_names.h rlim_names.h @@ -18,7 +19,11 @@ quiet_cmd_make-caps = GEN $@ cmd_make-caps = echo "static const char *const capability_names[] = {" > $@ ;\ sed $< >>$@ -r -n -e '/CAP_FS_MASK/d' \ -e 's/^\#define[ \t]+CAP_([A-Z0-9_]+)[ \t]+([0-9]+)/[\2] = "\L\1",/p';\ - echo "};" >> $@ + echo "};" >> $@ ;\ + echo -n '\#define AA_FS_CAPS_MASK "' >> $@ ;\ + sed $< -r -n -e '/CAP_FS_MASK/d' \ + -e 's/^\#define[ \t]+CAP_([A-Z0-9_]+)[ \t]+([0-9]+)/\L\1/p' | \ + tr '\n' ' ' | sed -e 's/ $$/"\n/' >> $@ # Build a lower case string table of rlimit names. diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 16c15ec..95c2b26 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -12,6 +12,7 @@ * License. */ +#include <linux/ctype.h> #include <linux/security.h> #include <linux/vmalloc.h> #include <linux/module.h> @@ -19,15 +20,56 @@ #include <linux/uaccess.h> #include <linux/namei.h> #include <linux/capability.h> +#include <linux/rcupdate.h> #include "include/apparmor.h" #include "include/apparmorfs.h" #include "include/audit.h" #include "include/context.h" +#include "include/crypto.h" #include "include/policy.h" #include "include/resource.h" /** + * aa_mangle_name - mangle a profile name to std profile layout form + * @name: profile name to mangle (NOT NULL) + * @target: buffer to store mangled name, same length as @name (MAYBE NULL) + * + * Returns: length of mangled name + */ +static int mangle_name(char *name, char *target) +{ + char *t = target; + + while (*name == '/' || *name == '.') + name++; + + if (target) { + for (; *name; name++) { + if (*name == '/') + *(t)++ = '.'; + else if (isspace(*name)) + *(t)++ = '_'; + else if (isalnum(*name) || strchr("._-", *name)) + *(t)++ = *name; + } + + *t = 0; + } else { + int len = 0; + for (; *name; name++) { + if (isalnum(*name) || isspace(*name) || + strchr("/._-", *name)) + len++; + } + + return len; + } + + return t - target; +} + +/** * aa_simple_write_to_buffer - common routine for getting policy from user * @op: operation doing the user buffer copy * @userbuf: user buffer to copy data from (NOT NULL) @@ -182,8 +224,567 @@ const struct file_operations aa_fs_seq_file_ops = { .release = single_release, }; -/** Base file system setup **/ +static int aa_fs_seq_profile_open(struct inode *inode, struct file *file, + int (*show)(struct seq_file *, void *)) +{ + struct aa_replacedby *r = aa_get_replacedby(inode->i_private); + int error = single_open(file, show, r); + + if (error) { + file->private_data = NULL; + aa_put_replacedby(r); + } + + return error; +} + +static int aa_fs_seq_profile_release(struct inode *inode, struct file *file) +{ + struct seq_file *seq = (struct seq_file *) file->private_data; + if (seq) + aa_put_replacedby(seq->private); + return single_release(inode, file); +} + +static int aa_fs_seq_profname_show(struct seq_file *seq, void *v) +{ + struct aa_replacedby *r = seq->private; + struct aa_profile *profile = aa_get_profile_rcu(&r->profile); + seq_printf(seq, "%s\n", profile->base.name); + aa_put_profile(profile); + + return 0; +} + +static int aa_fs_seq_profname_open(struct inode *inode, struct file *file) +{ + return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profname_show); +} + +static const struct file_operations aa_fs_profname_fops = { + .owner = THIS_MODULE, + .open = aa_fs_seq_profname_open, + .read = seq_read, + .llseek = seq_lseek, + .release = aa_fs_seq_profile_release, +}; + +static int aa_fs_seq_profmode_show(struct seq_file *seq, void *v) +{ + struct aa_replacedby *r = seq->private; + struct aa_profile *profile = aa_get_profile_rcu(&r->profile); + seq_printf(seq, "%s\n", aa_profile_mode_names[profile->mode]); + aa_put_profile(profile); + + return 0; +} + +static int aa_fs_seq_profmode_open(struct inode *inode, struct file *file) +{ + return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profmode_show); +} + +static const struct file_operations aa_fs_profmode_fops = { + .owner = THIS_MODULE, + .open = aa_fs_seq_profmode_open, + .read = seq_read, + .llseek = seq_lseek, + .release = aa_fs_seq_profile_release, +}; + +static int aa_fs_seq_profattach_show(struct seq_file *seq, void *v) +{ + struct aa_replacedby *r = seq->private; + struct aa_profile *profile = aa_get_profile_rcu(&r->profile); + if (profile->attach) + seq_printf(seq, "%s\n", profile->attach); + else if (profile->xmatch) + seq_puts(seq, "<unknown>\n"); + else + seq_printf(seq, "%s\n", profile->base.name); + aa_put_profile(profile); + + return 0; +} + +static int aa_fs_seq_profattach_open(struct inode *inode, struct file *file) +{ + return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profattach_show); +} + +static const struct file_operations aa_fs_profattach_fops = { + .owner = THIS_MODULE, + .open = aa_fs_seq_profattach_open, + .read = seq_read, + .llseek = seq_lseek, + .release = aa_fs_seq_profile_release, +}; + +static int aa_fs_seq_hash_show(struct seq_file *seq, void *v) +{ + struct aa_replacedby *r = seq->private; + struct aa_profile *profile = aa_get_profile_rcu(&r->profile); + unsigned int i, size = aa_hash_size(); + + if (profile->hash) { + for (i = 0; i < size; i++) + seq_printf(seq, "%.2x", profile->hash[i]); + seq_puts(seq, "\n"); + } + + return 0; +} + +static int aa_fs_seq_hash_open(struct inode *inode, struct file *file) +{ + return single_open(file, aa_fs_seq_hash_show, inode->i_private); +} + +static const struct file_operations aa_fs_seq_hash_fops = { + .owner = THIS_MODULE, + .open = aa_fs_seq_hash_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +/** fns to setup dynamic per profile/namespace files **/ +void __aa_fs_profile_rmdir(struct aa_profile *profile) +{ + struct aa_profile *child; + int i; + + if (!profile) + return; + + list_for_each_entry(child, &profile->base.profiles, base.list) + __aa_fs_profile_rmdir(child); + + for (i = AAFS_PROF_SIZEOF - 1; i >= 0; --i) { + struct aa_replacedby *r; + if (!profile->dents[i]) + continue; + + r = profile->dents[i]->d_inode->i_private; + securityfs_remove(profile->dents[i]); + aa_put_replacedby(r); + profile->dents[i] = NULL; + } +} + +void __aa_fs_profile_migrate_dents(struct aa_profile *old, + struct aa_profile *new) +{ + int i; + + for (i = 0; i < AAFS_PROF_SIZEOF; i++) { + new->dents[i] = old->dents[i]; + old->dents[i] = NULL; + } +} + +static struct dentry *create_profile_file(struct dentry *dir, const char *name, + struct aa_profile *profile, + const struct file_operations *fops) +{ + struct aa_replacedby *r = aa_get_replacedby(profile->replacedby); + struct dentry *dent; + + dent = securityfs_create_file(name, S_IFREG | 0444, dir, r, fops); + if (IS_ERR(dent)) + aa_put_replacedby(r); + + return dent; +} + +/* requires lock be held */ +int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent) +{ + struct aa_profile *child; + struct dentry *dent = NULL, *dir; + int error; + + if (!parent) { + struct aa_profile *p; + p = aa_deref_parent(profile); + dent = prof_dir(p); + /* adding to parent that previously didn't have children */ + dent = securityfs_create_dir("profiles", dent); + if (IS_ERR(dent)) + goto fail; + prof_child_dir(p) = parent = dent; + } + + if (!profile->dirname) { + int len, id_len; + len = mangle_name(profile->base.name, NULL); + id_len = snprintf(NULL, 0, ".%ld", profile->ns->uniq_id); + + profile->dirname = kmalloc(len + id_len + 1, GFP_KERNEL); + if (!profile->dirname) + goto fail; + + mangle_name(profile->base.name, profile->dirname); + sprintf(profile->dirname + len, ".%ld", profile->ns->uniq_id++); + } + + dent = securityfs_create_dir(profile->dirname, parent); + if (IS_ERR(dent)) + goto fail; + prof_dir(profile) = dir = dent; + + dent = create_profile_file(dir, "name", profile, &aa_fs_profname_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_NAME] = dent; + + dent = create_profile_file(dir, "mode", profile, &aa_fs_profmode_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_MODE] = dent; + + dent = create_profile_file(dir, "attach", profile, + &aa_fs_profattach_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_ATTACH] = dent; + + if (profile->hash) { + dent = create_profile_file(dir, "sha1", profile, + &aa_fs_seq_hash_fops); + if (IS_ERR(dent)) + goto fail; + profile->dents[AAFS_PROF_HASH] = dent; + } + + list_for_each_entry(child, &profile->base.profiles, base.list) { + error = __aa_fs_profile_mkdir(child, prof_child_dir(profile)); + if (error) + goto fail2; + } + + return 0; + +fail: + error = PTR_ERR(dent); + +fail2: + __aa_fs_profile_rmdir(profile); + + return error; +} + +void __aa_fs_namespace_rmdir(struct aa_namespace *ns) +{ + struct aa_namespace *sub; + struct aa_profile *child; + int i; + + if (!ns) + return; + + list_for_each_entry(child, &ns->base.profiles, base.list) + __aa_fs_profile_rmdir(child); + + list_for_each_entry(sub, &ns->sub_ns, base.list) { + mutex_lock(&sub->lock); + __aa_fs_namespace_rmdir(sub); + mutex_unlock(&sub->lock); + } + for (i = AAFS_NS_SIZEOF - 1; i >= 0; --i) { + securityfs_remove(ns->dents[i]); + ns->dents[i] = NULL; + } +} + +int __aa_fs_namespace_mkdir(struct aa_namespace *ns, struct dentry *parent, + const char *name) +{ + struct aa_namespace *sub; + struct aa_profile *child; + struct dentry *dent, *dir; + int error; + + if (!name) + name = ns->base.name; + + dent = securityfs_create_dir(name, parent); + if (IS_ERR(dent)) + goto fail; + ns_dir(ns) = dir = dent; + + dent = securityfs_create_dir("profiles", dir); + if (IS_ERR(dent)) + goto fail; + ns_subprofs_dir(ns) = dent; + + dent = securityfs_create_dir("namespaces", dir); + if (IS_ERR(dent)) + goto fail; + ns_subns_dir(ns) = dent; + + list_for_each_entry(child, &ns->base.profiles, base.list) { + error = __aa_fs_profile_mkdir(child, ns_subprofs_dir(ns)); + if (error) + goto fail2; + } + + list_for_each_entry(sub, &ns->sub_ns, base.list) { + mutex_lock(&sub->lock); + error = __aa_fs_namespace_mkdir(sub, ns_subns_dir(ns), NULL); + mutex_unlock(&sub->lock); + if (error) + goto fail2; + } + + return 0; + +fail: + error = PTR_ERR(dent); + +fail2: + __aa_fs_namespace_rmdir(ns); + + return error; +} + + +#define list_entry_next(pos, member) \ + list_entry(pos->member.next, typeof(*pos), member) +#define list_entry_is_head(pos, head, member) (&pos->member == (head)) + +/** + * __next_namespace - find the next namespace to list + * @root: root namespace to stop search at (NOT NULL) + * @ns: current ns position (NOT NULL) + * + * Find the next namespace from @ns under @root and handle all locking needed + * while switching current namespace. + * + * Returns: next namespace or NULL if at last namespace under @root + * Requires: ns->parent->lock to be held + * NOTE: will not unlock root->lock + */ +static struct aa_namespace *__next_namespace(struct aa_namespace *root, + struct aa_namespace *ns) +{ + struct aa_namespace *parent, *next; + + /* is next namespace a child */ + if (!list_empty(&ns->sub_ns)) { + next = list_first_entry(&ns->sub_ns, typeof(*ns), base.list); + mutex_lock(&next->lock); + return next; + } + + /* check if the next ns is a sibling, parent, gp, .. */ + parent = ns->parent; + while (parent) { + mutex_unlock(&ns->lock); + next = list_entry_next(ns, base.list); + if (!list_entry_is_head(next, &parent->sub_ns, base.list)) { + mutex_lock(&next->lock); + return next; + } + if (parent == root) + return NULL; + ns = parent; + parent = parent->parent; + } + + return NULL; +} + +/** + * __first_profile - find the first profile in a namespace + * @root: namespace that is root of profiles being displayed (NOT NULL) + * @ns: namespace to start in (NOT NULL) + * + * Returns: unrefcounted profile or NULL if no profile + * Requires: profile->ns.lock to be held + */ +static struct aa_profile *__first_profile(struct aa_namespace *root, + struct aa_namespace *ns) +{ + for (; ns; ns = __next_namespace(root, ns)) { + if (!list_empty(&ns->base.profiles)) + return list_first_entry(&ns->base.profiles, + struct aa_profile, base.list); + } + return NULL; +} + +/** + * __next_profile - step to the next profile in a profile tree + * @profile: current profile in tree (NOT NULL) + * + * Perform a depth first traversal on the profile tree in a namespace + * + * Returns: next profile or NULL if done + * Requires: profile->ns.lock to be held + */ +static struct aa_profile *__next_profile(struct aa_profile *p) +{ + struct aa_profile *parent; + struct aa_namespace *ns = p->ns; + + /* is next profile a child */ + if (!list_empty(&p->base.profiles)) + return list_first_entry(&p->base.profiles, typeof(*p), + base.list); + + /* is next profile a sibling, parent sibling, gp, sibling, .. */ + parent = rcu_dereference_protected(p->parent, + mutex_is_locked(&p->ns->lock)); + while (parent) { + p = list_entry_next(p, base.list); + if (!list_entry_is_head(p, &parent->base.profiles, base.list)) + return p; + p = parent; + parent = rcu_dereference_protected(parent->parent, + mutex_is_locked(&parent->ns->lock)); + } + + /* is next another profile in the namespace */ + p = list_entry_next(p, base.list); + if (!list_entry_is_head(p, &ns->base.profiles, base.list)) + return p; + + return NULL; +} + +/** + * next_profile - step to the next profile in where ever it may be + * @root: root namespace (NOT NULL) + * @profile: current profile (NOT NULL) + * + * Returns: next profile or NULL if there isn't one + */ +static struct aa_profile *next_profile(struct aa_namespace *root, + struct aa_profile *profile) +{ + struct aa_profile *next = __next_profile(profile); + if (next) + return next; + + /* finished all profiles in namespace move to next namespace */ + return __first_profile(root, __next_namespace(root, profile->ns)); +} + +/** + * p_start - start a depth first traversal of profile tree + * @f: seq_file to fill + * @pos: current position + * + * Returns: first profile under current namespace or NULL if none found + * + * acquires first ns->lock + */ +static void *p_start(struct seq_file *f, loff_t *pos) +{ + struct aa_profile *profile = NULL; + struct aa_namespace *root = aa_current_profile()->ns; + loff_t l = *pos; + f->private = aa_get_namespace(root); + + + /* find the first profile */ + mutex_lock(&root->lock); + profile = __first_profile(root, root); + + /* skip to position */ + for (; profile && l > 0; l--) + profile = next_profile(root, profile); + + return profile; +} + +/** + * p_next - read the next profile entry + * @f: seq_file to fill + * @p: profile previously returned + * @pos: current position + * + * Returns: next profile after @p or NULL if none + * + * may acquire/release locks in namespace tree as necessary + */ +static void *p_next(struct seq_file *f, void *p, loff_t *pos) +{ + struct aa_profile *profile = p; + struct aa_namespace *ns = f->private; + (*pos)++; + + return next_profile(ns, profile); +} + +/** + * p_stop - stop depth first traversal + * @f: seq_file we are filling + * @p: the last profile writen + * + * Release all locking done by p_start/p_next on namespace tree + */ +static void p_stop(struct seq_file *f, void *p) +{ + struct aa_profile *profile = p; + struct aa_namespace *root = f->private, *ns; + + if (profile) { + for (ns = profile->ns; ns && ns != root; ns = ns->parent) + mutex_unlock(&ns->lock); + } + mutex_unlock(&root->lock); + aa_put_namespace(root); +} + +/** + * seq_show_profile - show a profile entry + * @f: seq_file to file + * @p: current position (profile) (NOT NULL) + * + * Returns: error on failure + */ +static int seq_show_profile(struct seq_file *f, void *p) +{ + struct aa_profile *profile = (struct aa_profile *)p; + struct aa_namespace *root = f->private; + + if (profile->ns != root) + seq_printf(f, ":%s://", aa_ns_name(root, profile->ns)); + seq_printf(f, "%s (%s)\n", profile->base.hname, + aa_profile_mode_names[profile->mode]); + + return 0; +} + +static const struct seq_operations aa_fs_profiles_op = { + .start = p_start, + .next = p_next, + .stop = p_stop, + .show = seq_show_profile, +}; + +static int profiles_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &aa_fs_profiles_op); +} + +static int profiles_release(struct inode *inode, struct file *file) +{ + return seq_release(inode, file); +} + +static const struct file_operations aa_fs_profiles_fops = { + .open = profiles_open, + .read = seq_read, + .llseek = seq_lseek, + .release = profiles_release, +}; + + +/** Base file system setup **/ static struct aa_fs_entry aa_fs_entry_file[] = { AA_FS_FILE_STRING("mask", "create read write exec append mmap_exec " \ "link lock"), @@ -198,11 +799,18 @@ static struct aa_fs_entry aa_fs_entry_domain[] = { { } }; +static struct aa_fs_entry aa_fs_entry_policy[] = { + AA_FS_FILE_BOOLEAN("set_load", 1), + {} +}; + static struct aa_fs_entry aa_fs_entry_features[] = { + AA_FS_DIR("policy", aa_fs_entry_policy), AA_FS_DIR("domain", aa_fs_entry_domain), AA_FS_DIR("file", aa_fs_entry_file), AA_FS_FILE_U64("capability", VFS_CAP_FLAGS_MASK), AA_FS_DIR("rlimit", aa_fs_entry_rlimit), + AA_FS_DIR("caps", aa_fs_entry_caps), { } }; @@ -210,6 +818,7 @@ static struct aa_fs_entry aa_fs_entry_apparmor[] = { AA_FS_FILE_FOPS(".load", 0640, &aa_fs_profile_load), AA_FS_FILE_FOPS(".replace", 0640, &aa_fs_profile_replace), AA_FS_FILE_FOPS(".remove", 0640, &aa_fs_profile_remove), + AA_FS_FILE_FOPS("profiles", 0640, &aa_fs_profiles_fops), AA_FS_DIR("features", aa_fs_entry_features), { } }; @@ -240,6 +849,7 @@ static int __init aafs_create_file(struct aa_fs_entry *fs_file, return error; } +static void __init aafs_remove_dir(struct aa_fs_entry *fs_dir); /** * aafs_create_dir - recursively create a directory entry in the securityfs * @fs_dir: aa_fs_entry (and all child entries) to build (NOT NULL) @@ -250,17 +860,16 @@ static int __init aafs_create_file(struct aa_fs_entry *fs_file, static int __init aafs_create_dir(struct aa_fs_entry *fs_dir, struct dentry *parent) { - int error; struct aa_fs_entry *fs_file; + struct dentry *dir; + int error; - fs_dir->dentry = securityfs_create_dir(fs_dir->name, parent); - if (IS_ERR(fs_dir->dentry)) { - error = PTR_ERR(fs_dir->dentry); - fs_dir->dentry = NULL; - goto failed; - } + dir = securityfs_create_dir(fs_dir->name, parent); + if (IS_ERR(dir)) + return PTR_ERR(dir); + fs_dir->dentry = dir; - for (fs_file = fs_dir->v.files; fs_file->name; ++fs_file) { + for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) { if (fs_file->v_type == AA_FS_TYPE_DIR) error = aafs_create_dir(fs_file, fs_dir->dentry); else @@ -272,6 +881,8 @@ static int __init aafs_create_dir(struct aa_fs_entry *fs_dir, return 0; failed: + aafs_remove_dir(fs_dir); + return error; } @@ -296,7 +907,7 @@ static void __init aafs_remove_dir(struct aa_fs_entry *fs_dir) { struct aa_fs_entry *fs_file; - for (fs_file = fs_dir->v.files; fs_file->name; ++fs_file) { + for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) { if (fs_file->v_type == AA_FS_TYPE_DIR) aafs_remove_dir(fs_file); else @@ -340,6 +951,11 @@ static int __init aa_create_aafs(void) if (error) goto error; + error = __aa_fs_namespace_mkdir(root_ns, aa_fs_entry.dentry, + "policy"); + if (error) + goto error; + /* TODO: add support for apparmorfs_null and apparmorfs_mnt */ /* Report that AppArmor fs is enabled */ diff --git a/security/apparmor/capability.c b/security/apparmor/capability.c index 887a5e9..84d1f5f 100644 --- a/security/apparmor/capability.c +++ b/security/apparmor/capability.c @@ -27,6 +27,11 @@ */ #include "capability_names.h" +struct aa_fs_entry aa_fs_entry_caps[] = { + AA_FS_FILE_STRING("mask", AA_FS_CAPS_MASK), + { } +}; + struct audit_cache { struct aa_profile *profile; kernel_cap_t caps; diff --git a/security/apparmor/context.c b/security/apparmor/context.c index d5af1d1..3064c6c 100644 --- a/security/apparmor/context.c +++ b/security/apparmor/context.c @@ -112,9 +112,9 @@ int aa_replace_current_profile(struct aa_profile *profile) aa_clear_task_cxt_trans(cxt); /* be careful switching cxt->profile, when racing replacement it - * is possible that cxt->profile->replacedby is the reference keeping - * @profile valid, so make sure to get its reference before dropping - * the reference on cxt->profile */ + * is possible that cxt->profile->replacedby->profile is the reference + * keeping @profile valid, so make sure to get its reference before + * dropping the reference on cxt->profile */ aa_get_profile(profile); aa_put_profile(cxt->profile); cxt->profile = profile; @@ -175,7 +175,7 @@ int aa_set_current_hat(struct aa_profile *profile, u64 token) abort_creds(new); return -EACCES; } - cxt->profile = aa_get_profile(aa_newest_version(profile)); + cxt->profile = aa_get_newest_profile(profile); /* clear exec on switching context */ aa_put_profile(cxt->onexec); cxt->onexec = NULL; @@ -212,14 +212,8 @@ int aa_restore_previous_profile(u64 token) } aa_put_profile(cxt->profile); - cxt->profile = aa_newest_version(cxt->previous); + cxt->profile = aa_get_newest_profile(cxt->previous); BUG_ON(!cxt->profile); - if (unlikely(cxt->profile != cxt->previous)) { - aa_get_profile(cxt->profile); - aa_put_profile(cxt->previous); - } - /* ref has been transfered so avoid putting ref in clear_task_cxt */ - cxt->previous = NULL; /* clear exec && prev information when restoring to previous context */ aa_clear_task_cxt_trans(cxt); diff --git a/security/apparmor/crypto.c b/security/apparmor/crypto.c new file mode 100644 index 0000000..d6222ba --- /dev/null +++ b/security/apparmor/crypto.c @@ -0,0 +1,97 @@ +/* + * AppArmor security module + * + * This file contains AppArmor policy loading interface function definitions. + * + * Copyright 2013 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * Fns to provide a checksum of policy that has been loaded this can be + * compared to userspace policy compiles to check loaded policy is what + * it should be. + */ + +#include <linux/crypto.h> + +#include "include/apparmor.h" +#include "include/crypto.h" + +static unsigned int apparmor_hash_size; + +static struct crypto_hash *apparmor_tfm; + +unsigned int aa_hash_size(void) +{ + return apparmor_hash_size; +} + +int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start, + size_t len) +{ + struct scatterlist sg[2]; + struct hash_desc desc = { + .tfm = apparmor_tfm, + .flags = 0 + }; + int error = -ENOMEM; + u32 le32_version = cpu_to_le32(version); + + if (!apparmor_tfm) + return 0; + + sg_init_table(sg, 2); + sg_set_buf(&sg[0], &le32_version, 4); + sg_set_buf(&sg[1], (u8 *) start, len); + + profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL); + if (!profile->hash) + goto fail; + + error = crypto_hash_init(&desc); + if (error) + goto fail; + error = crypto_hash_update(&desc, &sg[0], 4); + if (error) + goto fail; + error = crypto_hash_update(&desc, &sg[1], len); + if (error) + goto fail; + error = crypto_hash_final(&desc, profile->hash); + if (error) + goto fail; + + return 0; + +fail: + kfree(profile->hash); + profile->hash = NULL; + + return error; +} + +static int __init init_profile_hash(void) +{ + struct crypto_hash *tfm; + + if (!apparmor_initialized) + return 0; + + tfm = crypto_alloc_hash("sha1", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(tfm)) { + int error = PTR_ERR(tfm); + AA_ERROR("failed to setup profile sha1 hashing: %d\n", error); + return error; + } + apparmor_tfm = tfm; + apparmor_hash_size = crypto_hash_digestsize(apparmor_tfm); + + aa_info_message("AppArmor sha1 policy hashing enabled"); + + return 0; +} + +late_initcall(init_profile_hash); diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c index 01b7bd6..26c607c 100644 --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -144,7 +144,7 @@ static struct aa_profile *__attach_match(const char *name, int len = 0; struct aa_profile *profile, *candidate = NULL; - list_for_each_entry(profile, head, base.list) { + list_for_each_entry_rcu(profile, head, base.list) { if (profile->flags & PFLAG_NULL) continue; if (profile->xmatch && profile->xmatch_len > len) { @@ -177,9 +177,9 @@ static struct aa_profile *find_attach(struct aa_namespace *ns, { struct aa_profile *profile; - read_lock(&ns->lock); + rcu_read_lock(); profile = aa_get_profile(__attach_match(name, list)); - read_unlock(&ns->lock); + rcu_read_unlock(); return profile; } @@ -359,7 +359,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm) cxt = cred_cxt(bprm->cred); BUG_ON(!cxt); - profile = aa_get_profile(aa_newest_version(cxt->profile)); + profile = aa_get_newest_profile(cxt->profile); /* * get the namespace from the replacement profile as replacement * can change the namespace @@ -371,8 +371,8 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm) error = aa_path_name(&bprm->file->f_path, profile->path_flags, &buffer, &name, &info); if (error) { - if (profile->flags & - (PFLAG_IX_ON_NAME_ERROR | PFLAG_UNCONFINED)) + if (unconfined(profile) || + (profile->flags & PFLAG_IX_ON_NAME_ERROR)) error = 0; name = bprm->filename; goto audit; @@ -417,7 +417,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm) if (!(cp.allow & AA_MAY_ONEXEC)) goto audit; - new_profile = aa_get_profile(aa_newest_version(cxt->onexec)); + new_profile = aa_get_newest_profile(cxt->onexec); goto apply; } @@ -434,7 +434,7 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm) new_profile = aa_get_profile(profile); goto x_clear; } else if (perms.xindex & AA_X_UNCONFINED) { - new_profile = aa_get_profile(ns->unconfined); + new_profile = aa_get_newest_profile(ns->unconfined); info = "ux fallback"; } else { error = -ENOENT; @@ -641,7 +641,10 @@ int aa_change_hat(const char *hats[], int count, u64 token, bool permtest) if (count) { /* attempting to change into a new hat or switch to a sibling */ struct aa_profile *root; - root = PROFILE_IS_HAT(profile) ? profile->parent : profile; + if (PROFILE_IS_HAT(profile)) + root = aa_get_profile_rcu(&profile->parent); + else + root = aa_get_profile(profile); /* find first matching hat */ for (i = 0; i < count && !hat; i++) @@ -653,6 +656,7 @@ int aa_change_hat(const char *hats[], int count, u64 token, bool permtest) error = -ECHILD; else error = -ENOENT; + aa_put_profile(root); goto out; } @@ -667,6 +671,7 @@ int aa_change_hat(const char *hats[], int count, u64 token, bool permtest) /* freed below */ name = new_compound_name(root->base.hname, hats[0]); + aa_put_profile(root); target = name; /* released below */ hat = aa_new_null_profile(profile, 1); @@ -676,6 +681,7 @@ int aa_change_hat(const char *hats[], int count, u64 token, bool permtest) goto audit; } } else { + aa_put_profile(root); target = hat->base.hname; if (!PROFILE_IS_HAT(hat)) { info = "target not hat"; diff --git a/security/apparmor/include/apparmor.h b/security/apparmor/include/apparmor.h index 1ba2ca5..8fb1488 100644 --- a/security/apparmor/include/apparmor.h +++ b/security/apparmor/include/apparmor.h @@ -78,6 +78,12 @@ static inline void *kvzalloc(size_t size) return __aa_kvmalloc(size, __GFP_ZERO); } +/* returns 0 if kref not incremented */ +static inline int kref_get_not0(struct kref *kref) +{ + return atomic_inc_not_zero(&kref->refcount); +} + /** * aa_strneq - compare null terminated @str to a non null terminated substring * @str: a null terminated string diff --git a/security/apparmor/include/apparmorfs.h b/security/apparmor/include/apparmorfs.h index 7ea4769..414e568 100644 --- a/security/apparmor/include/apparmorfs.h +++ b/security/apparmor/include/apparmorfs.h @@ -61,4 +61,44 @@ extern const struct file_operations aa_fs_seq_file_ops; extern void __init aa_destroy_aafs(void); +struct aa_profile; +struct aa_namespace; + +enum aafs_ns_type { + AAFS_NS_DIR, + AAFS_NS_PROFS, + AAFS_NS_NS, + AAFS_NS_COUNT, + AAFS_NS_MAX_COUNT, + AAFS_NS_SIZE, + AAFS_NS_MAX_SIZE, + AAFS_NS_OWNER, + AAFS_NS_SIZEOF, +}; + +enum aafs_prof_type { + AAFS_PROF_DIR, + AAFS_PROF_PROFS, + AAFS_PROF_NAME, + AAFS_PROF_MODE, + AAFS_PROF_ATTACH, + AAFS_PROF_HASH, + AAFS_PROF_SIZEOF, +}; + +#define ns_dir(X) ((X)->dents[AAFS_NS_DIR]) +#define ns_subns_dir(X) ((X)->dents[AAFS_NS_NS]) +#define ns_subprofs_dir(X) ((X)->dents[AAFS_NS_PROFS]) + +#define prof_dir(X) ((X)->dents[AAFS_PROF_DIR]) +#define prof_child_dir(X) ((X)->dents[AAFS_PROF_PROFS]) + +void __aa_fs_profile_rmdir(struct aa_profile *profile); +void __aa_fs_profile_migrate_dents(struct aa_profile *old, + struct aa_profile *new); +int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent); +void __aa_fs_namespace_rmdir(struct aa_namespace *ns); +int __aa_fs_namespace_mkdir(struct aa_namespace *ns, struct dentry *parent, + const char *name); + #endif /* __AA_APPARMORFS_H */ diff --git a/security/apparmor/include/audit.h b/security/apparmor/include/audit.h index 69d8cae..30e8d76 100644 --- a/security/apparmor/include/audit.h +++ b/security/apparmor/include/audit.h @@ -27,7 +27,6 @@ struct aa_profile; extern const char *const audit_mode_names[]; #define AUDIT_MAX_INDEX 5 - enum audit_mode { AUDIT_NORMAL, /* follow normal auditing of accesses */ AUDIT_QUIET_DENIED, /* quiet all denied access messages */ diff --git a/security/apparmor/include/capability.h b/security/apparmor/include/capability.h index c24d295..2e7c9d6 100644 --- a/security/apparmor/include/capability.h +++ b/security/apparmor/include/capability.h @@ -17,6 +17,8 @@ #include <linux/sched.h> +#include "apparmorfs.h" + struct aa_profile; /* aa_caps - confinement data for capabilities @@ -34,6 +36,8 @@ struct aa_caps { kernel_cap_t extended; }; +extern struct aa_fs_entry aa_fs_entry_caps[]; + int aa_capable(struct task_struct *task, struct aa_profile *profile, int cap, int audit); diff --git a/security/apparmor/include/context.h b/security/apparmor/include/context.h index d44ba58..6bf6579 100644 --- a/security/apparmor/include/context.h +++ b/security/apparmor/include/context.h @@ -98,7 +98,7 @@ static inline struct aa_profile *aa_cred_profile(const struct cred *cred) { struct aa_task_cxt *cxt = cred_cxt(cred); BUG_ON(!cxt || !cxt->profile); - return aa_newest_version(cxt->profile); + return cxt->profile; } /** @@ -152,15 +152,14 @@ static inline struct aa_profile *aa_current_profile(void) struct aa_profile *profile; BUG_ON(!cxt || !cxt->profile); - profile = aa_newest_version(cxt->profile); - /* - * Whether or not replacement succeeds, use newest profile so - * there is no need to update it after replacement. - */ - if (unlikely((cxt->profile != profile))) + if (PROFILE_INVALID(cxt->profile)) { + profile = aa_get_newest_profile(cxt->profile); aa_replace_current_profile(profile); + aa_put_profile(profile); + cxt = current_cxt(); + } - return profile; + return cxt->profile; } /** diff --git a/security/apparmor/include/crypto.h b/security/apparmor/include/crypto.h new file mode 100644 index 0000000..dc418e5 --- /dev/null +++ b/security/apparmor/include/crypto.h @@ -0,0 +1,36 @@ +/* + * AppArmor security module + * + * This file contains AppArmor policy loading interface function definitions. + * + * Copyright 2013 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#ifndef __APPARMOR_CRYPTO_H +#define __APPARMOR_CRYPTO_H + +#include "policy.h" + +#ifdef CONFIG_SECURITY_APPARMOR_HASH +unsigned int aa_hash_size(void); +int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start, + size_t len); +#else +static inline int aa_calc_profile_hash(struct aa_profile *profile, u32 version, + void *start, size_t len) +{ + return 0; +} + +static inline unsigned int aa_hash_size(void) +{ + return 0; +} +#endif + +#endif /* __APPARMOR_CRYPTO_H */ diff --git a/security/apparmor/include/policy.h b/security/apparmor/include/policy.h index b25491a..f2d4b63 100644 --- a/security/apparmor/include/policy.h +++ b/security/apparmor/include/policy.h @@ -29,8 +29,8 @@ #include "file.h" #include "resource.h" -extern const char *const profile_mode_names[]; -#define APPARMOR_NAMES_MAX_INDEX 3 +extern const char *const aa_profile_mode_names[]; +#define APPARMOR_MODE_NAMES_MAX_INDEX 4 #define PROFILE_MODE(_profile, _mode) \ ((aa_g_profile_mode == (_mode)) || \ @@ -42,6 +42,10 @@ extern const char *const profile_mode_names[]; #define PROFILE_IS_HAT(_profile) ((_profile)->flags & PFLAG_HAT) +#define PROFILE_INVALID(_profile) ((_profile)->flags & PFLAG_INVALID) + +#define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2) + /* * FIXME: currently need a clean way to replace and remove profiles as a * set. It should be done at the namespace level. @@ -52,17 +56,19 @@ enum profile_mode { APPARMOR_ENFORCE, /* enforce access rules */ APPARMOR_COMPLAIN, /* allow and log access violations */ APPARMOR_KILL, /* kill task on access violation */ + APPARMOR_UNCONFINED, /* profile set to unconfined */ }; enum profile_flags { PFLAG_HAT = 1, /* profile is a hat */ - PFLAG_UNCONFINED = 2, /* profile is an unconfined profile */ PFLAG_NULL = 4, /* profile is null learning profile */ PFLAG_IX_ON_NAME_ERROR = 8, /* fallback to ix on name lookup fail */ PFLAG_IMMUTABLE = 0x10, /* don't allow changes/replacement */ PFLAG_USER_DEFINED = 0x20, /* user based profile - lower privs */ PFLAG_NO_LIST_REF = 0x40, /* list doesn't keep profile ref */ PFLAG_OLD_NULL_TRANS = 0x100, /* use // as the null transition */ + PFLAG_INVALID = 0x200, /* profile replaced/removed */ + PFLAG_NS_COUNT = 0x400, /* carries NS ref count */ /* These flags must correspond with PATH_flags */ PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */ @@ -73,14 +79,12 @@ struct aa_profile; /* struct aa_policy - common part of both namespaces and profiles * @name: name of the object * @hname - The hierarchical name - * @count: reference count of the obj * @list: list policy object is on * @profiles: head of the profiles list contained in the object */ struct aa_policy { char *name; char *hname; - struct kref count; struct list_head list; struct list_head profiles; }; @@ -106,6 +110,8 @@ struct aa_ns_acct { * @unconfined: special unconfined profile for the namespace * @sub_ns: list of namespaces under the current namespace. * @uniq_null: uniq value used for null learning profiles + * @uniq_id: a unique id count for the profiles in the namespace + * @dents: dentries for the namespaces file entries in apparmorfs * * An aa_namespace defines the set profiles that are searched to determine * which profile to attach to a task. Profiles can not be shared between @@ -124,11 +130,14 @@ struct aa_ns_acct { struct aa_namespace { struct aa_policy base; struct aa_namespace *parent; - rwlock_t lock; + struct mutex lock; struct aa_ns_acct acct; struct aa_profile *unconfined; struct list_head sub_ns; atomic_t uniq_null; + long uniq_id; + + struct dentry *dents[AAFS_NS_SIZEOF]; }; /* struct aa_policydb - match engine for a policy @@ -142,12 +151,21 @@ struct aa_policydb { }; +struct aa_replacedby { + struct kref count; + struct aa_profile __rcu *profile; +}; + + /* struct aa_profile - basic confinement data * @base - base components of the profile (name, refcount, lists, lock ...) + * @count: reference count of the obj + * @rcu: rcu head used when removing from @list * @parent: parent of profile * @ns: namespace the profile is in * @replacedby: is set to the profile that replaced this profile * @rename: optional profile name that this profile renamed + * @attach: human readable attachment string * @xmatch: optional extended matching for unconfined executables names * @xmatch_len: xmatch prefix len, used to determine xmatch priority * @audit: the auditing mode of the profile @@ -160,13 +178,15 @@ struct aa_policydb { * @caps: capabilities for the profile * @rlimits: rlimits for the profile * + * @dents: dentries for the profiles file entries in apparmorfs + * @dirname: name of the profile dir in apparmorfs + * * The AppArmor profile contains the basic confinement data. Each profile * has a name, and exists in a namespace. The @name and @exec_match are * used to determine profile attachment against unconfined tasks. All other * attachments are determined by profile X transition rules. * - * The @replacedby field is write protected by the profile lock. Reads - * are assumed to be atomic, and are done without locking. + * The @replacedby struct is write protected by the profile lock. * * Profiles have a hierarchy where hats and children profiles keep * a reference to their parent. @@ -177,17 +197,20 @@ struct aa_policydb { */ struct aa_profile { struct aa_policy base; - struct aa_profile *parent; + struct kref count; + struct rcu_head rcu; + struct aa_profile __rcu *parent; struct aa_namespace *ns; - struct aa_profile *replacedby; + struct aa_replacedby *replacedby; const char *rename; + const char *attach; struct aa_dfa *xmatch; int xmatch_len; enum audit_mode audit; - enum profile_mode mode; - u32 flags; + long mode; + long flags; u32 path_flags; int size; @@ -195,6 +218,10 @@ struct aa_profile { struct aa_file_rules file; struct aa_caps caps; struct aa_rlimit rlimits; + + unsigned char *hash; + char *dirname; + struct dentry *dents[AAFS_PROF_SIZEOF]; }; extern struct aa_namespace *root_ns; @@ -211,43 +238,11 @@ void aa_free_namespace_kref(struct kref *kref); struct aa_namespace *aa_find_namespace(struct aa_namespace *root, const char *name); -static inline struct aa_policy *aa_get_common(struct aa_policy *c) -{ - if (c) - kref_get(&c->count); - - return c; -} - -/** - * aa_get_namespace - increment references count on @ns - * @ns: namespace to increment reference count of (MAYBE NULL) - * - * Returns: pointer to @ns, if @ns is NULL returns NULL - * Requires: @ns must be held with valid refcount when called - */ -static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns) -{ - if (ns) - kref_get(&(ns->base.count)); - - return ns; -} - -/** - * aa_put_namespace - decrement refcount on @ns - * @ns: namespace to put reference of - * - * Decrement reference count of @ns and if no longer in use free it - */ -static inline void aa_put_namespace(struct aa_namespace *ns) -{ - if (ns) - kref_put(&ns->base.count, aa_free_namespace_kref); -} +void aa_free_replacedby_kref(struct kref *kref); struct aa_profile *aa_alloc_profile(const char *name); struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat); +void aa_free_profile(struct aa_profile *profile); void aa_free_profile_kref(struct kref *kref); struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name); struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name); @@ -259,25 +254,13 @@ ssize_t aa_remove_profiles(char *name, size_t size); #define PROF_ADD 1 #define PROF_REPLACE 0 -#define unconfined(X) ((X)->flags & PFLAG_UNCONFINED) +#define unconfined(X) ((X)->mode == APPARMOR_UNCONFINED) -/** - * aa_newest_version - find the newest version of @profile - * @profile: the profile to check for newer versions of (NOT NULL) - * - * Returns: newest version of @profile, if @profile is the newest version - * return @profile. - * - * NOTE: the profile returned is not refcounted, The refcount on @profile - * must be held until the caller decides what to do with the returned newest - * version. - */ -static inline struct aa_profile *aa_newest_version(struct aa_profile *profile) -{ - while (profile->replacedby) - profile = profile->replacedby; - return profile; +static inline struct aa_profile *aa_deref_parent(struct aa_profile *p) +{ + return rcu_dereference_protected(p->parent, + mutex_is_locked(&p->ns->lock)); } /** @@ -290,19 +273,124 @@ static inline struct aa_profile *aa_newest_version(struct aa_profile *profile) static inline struct aa_profile *aa_get_profile(struct aa_profile *p) { if (p) - kref_get(&(p->base.count)); + kref_get(&(p->count)); return p; } /** + * aa_get_profile_not0 - increment refcount on profile @p found via lookup + * @p: profile (MAYBE NULL) + * + * Returns: pointer to @p if @p is NULL will return NULL + * Requires: @p must be held with valid refcount when called + */ +static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p) +{ + if (p && kref_get_not0(&p->count)) + return p; + + return NULL; +} + +/** + * aa_get_profile_rcu - increment a refcount profile that can be replaced + * @p: pointer to profile that can be replaced (NOT NULL) + * + * Returns: pointer to a refcounted profile. + * else NULL if no profile + */ +static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p) +{ + struct aa_profile *c; + + rcu_read_lock(); + do { + c = rcu_dereference(*p); + } while (c && !kref_get_not0(&c->count)); + rcu_read_unlock(); + + return c; +} + +/** + * aa_get_newest_profile - find the newest version of @profile + * @profile: the profile to check for newer versions of + * + * Returns: refcounted newest version of @profile taking into account + * replacement, renames and removals + * return @profile. + */ +static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p) +{ + if (!p) + return NULL; + + if (PROFILE_INVALID(p)) + return aa_get_profile_rcu(&p->replacedby->profile); + + return aa_get_profile(p); +} + +/** * aa_put_profile - decrement refcount on profile @p * @p: profile (MAYBE NULL) */ static inline void aa_put_profile(struct aa_profile *p) { if (p) - kref_put(&p->base.count, aa_free_profile_kref); + kref_put(&p->count, aa_free_profile_kref); +} + +static inline struct aa_replacedby *aa_get_replacedby(struct aa_replacedby *p) +{ + if (p) + kref_get(&(p->count)); + + return p; +} + +static inline void aa_put_replacedby(struct aa_replacedby *p) +{ + if (p) + kref_put(&p->count, aa_free_replacedby_kref); +} + +/* requires profile list write lock held */ +static inline void __aa_update_replacedby(struct aa_profile *orig, + struct aa_profile *new) +{ + struct aa_profile *tmp = rcu_dereference(orig->replacedby->profile); + rcu_assign_pointer(orig->replacedby->profile, aa_get_profile(new)); + orig->flags |= PFLAG_INVALID; + aa_put_profile(tmp); +} + +/** + * aa_get_namespace - increment references count on @ns + * @ns: namespace to increment reference count of (MAYBE NULL) + * + * Returns: pointer to @ns, if @ns is NULL returns NULL + * Requires: @ns must be held with valid refcount when called + */ +static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns) +{ + if (ns) + aa_get_profile(ns->unconfined); + + return ns; +} + +/** + * aa_put_namespace - decrement refcount on @ns + * @ns: namespace to put reference of + * + * Decrement reference count of @ns and if no longer in use free it + */ +static inline void aa_put_namespace(struct aa_namespace *ns) +{ + if (ns) + aa_put_profile(ns->unconfined); } static inline int AUDIT_MODE(struct aa_profile *profile) diff --git a/security/apparmor/include/policy_unpack.h b/security/apparmor/include/policy_unpack.h index a2dccca..c214fb8 100644 --- a/security/apparmor/include/policy_unpack.h +++ b/security/apparmor/include/policy_unpack.h @@ -15,6 +15,25 @@ #ifndef __POLICY_INTERFACE_H #define __POLICY_INTERFACE_H -struct aa_profile *aa_unpack(void *udata, size_t size, const char **ns); +#include <linux/list.h> + +struct aa_load_ent { + struct list_head list; + struct aa_profile *new; + struct aa_profile *old; + struct aa_profile *rename; +}; + +void aa_load_ent_free(struct aa_load_ent *ent); +struct aa_load_ent *aa_load_ent_alloc(void); + +#define PACKED_FLAG_HAT 1 + +#define PACKED_MODE_ENFORCE 0 +#define PACKED_MODE_COMPLAIN 1 +#define PACKED_MODE_KILL 2 +#define PACKED_MODE_UNCONFINED 3 + +int aa_unpack(void *udata, size_t size, struct list_head *lh, const char **ns); #endif /* __POLICY_INTERFACE_H */ diff --git a/security/apparmor/lib.c b/security/apparmor/lib.c index fcfe023..6968992 100644 --- a/security/apparmor/lib.c +++ b/security/apparmor/lib.c @@ -97,11 +97,6 @@ void *__aa_kvmalloc(size_t size, gfp_t flags) if (size <= (16*PAGE_SIZE)) buffer = kmalloc(size, flags | GFP_NOIO | __GFP_NOWARN); if (!buffer) { - /* see kvfree for why size must be at least work_struct size - * when allocated via vmalloc - */ - if (size < sizeof(struct work_struct)) - size = sizeof(struct work_struct); if (flags & __GFP_ZERO) buffer = vzalloc(size); else diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 2e2a0dd..fb99e18 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -508,19 +508,21 @@ static int apparmor_getprocattr(struct task_struct *task, char *name, /* released below */ const struct cred *cred = get_task_cred(task); struct aa_task_cxt *cxt = cred_cxt(cred); + struct aa_profile *profile = NULL; if (strcmp(name, "current") == 0) - error = aa_getprocattr(aa_newest_version(cxt->profile), - value); + profile = aa_get_newest_profile(cxt->profile); else if (strcmp(name, "prev") == 0 && cxt->previous) - error = aa_getprocattr(aa_newest_version(cxt->previous), - value); + profile = aa_get_newest_profile(cxt->previous); else if (strcmp(name, "exec") == 0 && cxt->onexec) - error = aa_getprocattr(aa_newest_version(cxt->onexec), - value); + profile = aa_get_newest_profile(cxt->onexec); else error = -EINVAL; + if (profile) + error = aa_getprocattr(profile, value); + + aa_put_profile(profile); put_cred(cred); return error; @@ -666,6 +668,7 @@ static int param_set_aabool(const char *val, const struct kernel_param *kp); static int param_get_aabool(char *buffer, const struct kernel_param *kp); #define param_check_aabool param_check_bool static struct kernel_param_ops param_ops_aabool = { + .flags = KERNEL_PARAM_FL_NOARG, .set = param_set_aabool, .get = param_get_aabool }; @@ -682,6 +685,7 @@ static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp); #define param_check_aalockpolicy param_check_bool static struct kernel_param_ops param_ops_aalockpolicy = { + .flags = KERNEL_PARAM_FL_NOARG, .set = param_set_aalockpolicy, .get = param_get_aalockpolicy }; @@ -742,7 +746,7 @@ module_param_named(paranoid_load, aa_g_paranoid_load, aabool, /* Boot time disable flag */ static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE; -module_param_named(enabled, apparmor_enabled, aabool, S_IRUSR); +module_param_named(enabled, apparmor_enabled, bool, S_IRUGO); static int __init apparmor_enabled_setup(char *str) { @@ -841,7 +845,7 @@ static int param_get_mode(char *buffer, struct kernel_param *kp) if (!apparmor_enabled) return -EINVAL; - return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]); + return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]); } static int param_set_mode(const char *val, struct kernel_param *kp) @@ -856,8 +860,8 @@ static int param_set_mode(const char *val, struct kernel_param *kp) if (!val) return -EINVAL; - for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) { - if (strcmp(val, profile_mode_names[i]) == 0) { + for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) { + if (strcmp(val, aa_profile_mode_names[i]) == 0) { aa_g_profile_mode = i; return 0; } diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c index 0f345c4..6172509 100644 --- a/security/apparmor/policy.c +++ b/security/apparmor/policy.c @@ -92,10 +92,11 @@ /* root profile namespace */ struct aa_namespace *root_ns; -const char *const profile_mode_names[] = { +const char *const aa_profile_mode_names[] = { "enforce", "complain", "kill", + "unconfined", }; /** @@ -141,7 +142,6 @@ static bool policy_init(struct aa_policy *policy, const char *prefix, policy->name = (char *)hname_tail(policy->hname); INIT_LIST_HEAD(&policy->list); INIT_LIST_HEAD(&policy->profiles); - kref_init(&policy->count); return 1; } @@ -153,13 +153,13 @@ static bool policy_init(struct aa_policy *policy, const char *prefix, static void policy_destroy(struct aa_policy *policy) { /* still contains profiles -- invalid */ - if (!list_empty(&policy->profiles)) { + if (on_list_rcu(&policy->profiles)) { AA_ERROR("%s: internal error, " "policy '%s' still contains profiles\n", __func__, policy->name); BUG(); } - if (!list_empty(&policy->list)) { + if (on_list_rcu(&policy->list)) { AA_ERROR("%s: internal error, policy '%s' still on list\n", __func__, policy->name); BUG(); @@ -174,7 +174,7 @@ static void policy_destroy(struct aa_policy *policy) * @head: list to search (NOT NULL) * @name: name to search for (NOT NULL) * - * Requires: correct locks for the @head list be held + * Requires: rcu_read_lock be held * * Returns: unrefcounted policy that match @name or NULL if not found */ @@ -182,7 +182,7 @@ static struct aa_policy *__policy_find(struct list_head *head, const char *name) { struct aa_policy *policy; - list_for_each_entry(policy, head, list) { + list_for_each_entry_rcu(policy, head, list) { if (!strcmp(policy->name, name)) return policy; } @@ -195,7 +195,7 @@ static struct aa_policy *__policy_find(struct list_head *head, const char *name) * @str: string to search for (NOT NULL) * @len: length of match required * - * Requires: correct locks for the @head list be held + * Requires: rcu_read_lock be held * * Returns: unrefcounted policy that match @str or NULL if not found * @@ -207,7 +207,7 @@ static struct aa_policy *__policy_strn_find(struct list_head *head, { struct aa_policy *policy; - list_for_each_entry(policy, head, list) { + list_for_each_entry_rcu(policy, head, list) { if (aa_strneq(policy->name, str, len)) return policy; } @@ -284,22 +284,19 @@ static struct aa_namespace *alloc_namespace(const char *prefix, goto fail_ns; INIT_LIST_HEAD(&ns->sub_ns); - rwlock_init(&ns->lock); + mutex_init(&ns->lock); /* released by free_namespace */ ns->unconfined = aa_alloc_profile("unconfined"); if (!ns->unconfined) goto fail_unconfined; - ns->unconfined->flags = PFLAG_UNCONFINED | PFLAG_IX_ON_NAME_ERROR | - PFLAG_IMMUTABLE; + ns->unconfined->flags = PFLAG_IX_ON_NAME_ERROR | + PFLAG_IMMUTABLE | PFLAG_NS_COUNT; + ns->unconfined->mode = APPARMOR_UNCONFINED; - /* - * released by free_namespace, however __remove_namespace breaks - * the cyclic references (ns->unconfined, and unconfined->ns) and - * replaces with refs to parent namespace unconfined - */ - ns->unconfined->ns = aa_get_namespace(ns); + /* ns and ns->unconfined share ns->unconfined refcount */ + ns->unconfined->ns = ns; atomic_set(&ns->uniq_null, 0); @@ -327,30 +324,19 @@ static void free_namespace(struct aa_namespace *ns) policy_destroy(&ns->base); aa_put_namespace(ns->parent); - if (ns->unconfined && ns->unconfined->ns == ns) - ns->unconfined->ns = NULL; - - aa_put_profile(ns->unconfined); + ns->unconfined->ns = NULL; + aa_free_profile(ns->unconfined); kzfree(ns); } /** - * aa_free_namespace_kref - free aa_namespace by kref (see aa_put_namespace) - * @kr: kref callback for freeing of a namespace (NOT NULL) - */ -void aa_free_namespace_kref(struct kref *kref) -{ - free_namespace(container_of(kref, struct aa_namespace, base.count)); -} - -/** * __aa_find_namespace - find a namespace on a list by @name * @head: list to search for namespace on (NOT NULL) * @name: name of namespace to look for (NOT NULL) * * Returns: unrefcounted namespace * - * Requires: ns lock be held + * Requires: rcu_read_lock be held */ static struct aa_namespace *__aa_find_namespace(struct list_head *head, const char *name) @@ -373,9 +359,9 @@ struct aa_namespace *aa_find_namespace(struct aa_namespace *root, { struct aa_namespace *ns = NULL; - read_lock(&root->lock); + rcu_read_lock(); ns = aa_get_namespace(__aa_find_namespace(&root->sub_ns, name)); - read_unlock(&root->lock); + rcu_read_unlock(); return ns; } @@ -392,7 +378,7 @@ static struct aa_namespace *aa_prepare_namespace(const char *name) root = aa_current_profile()->ns; - write_lock(&root->lock); + mutex_lock(&root->lock); /* if name isn't specified the profile is loaded to the current ns */ if (!name) { @@ -405,31 +391,23 @@ static struct aa_namespace *aa_prepare_namespace(const char *name) /* released by caller */ ns = aa_get_namespace(__aa_find_namespace(&root->sub_ns, name)); if (!ns) { - /* namespace not found */ - struct aa_namespace *new_ns; - write_unlock(&root->lock); - new_ns = alloc_namespace(root->base.hname, name); - if (!new_ns) - return NULL; - write_lock(&root->lock); - /* test for race when new_ns was allocated */ - ns = __aa_find_namespace(&root->sub_ns, name); - if (!ns) { - /* add parent ref */ - new_ns->parent = aa_get_namespace(root); - - list_add(&new_ns->base.list, &root->sub_ns); - /* add list ref */ - ns = aa_get_namespace(new_ns); - } else { - /* raced so free the new one */ - free_namespace(new_ns); - /* get reference on namespace */ - aa_get_namespace(ns); + ns = alloc_namespace(root->base.hname, name); + if (!ns) + goto out; + if (__aa_fs_namespace_mkdir(ns, ns_subns_dir(root), name)) { + AA_ERROR("Failed to create interface for ns %s\n", + ns->base.name); + free_namespace(ns); + ns = NULL; + goto out; } + ns->parent = aa_get_namespace(root); + list_add_rcu(&ns->base.list, &root->sub_ns); + /* add list ref */ + aa_get_namespace(ns); } out: - write_unlock(&root->lock); + mutex_unlock(&root->lock); /* return ref */ return ns; @@ -447,7 +425,7 @@ out: static void __list_add_profile(struct list_head *list, struct aa_profile *profile) { - list_add(&profile->base.list, list); + list_add_rcu(&profile->base.list, list); /* get list reference */ aa_get_profile(profile); } @@ -466,49 +444,8 @@ static void __list_add_profile(struct list_head *list, */ static void __list_remove_profile(struct aa_profile *profile) { - list_del_init(&profile->base.list); - if (!(profile->flags & PFLAG_NO_LIST_REF)) - /* release list reference */ - aa_put_profile(profile); -} - -/** - * __replace_profile - replace @old with @new on a list - * @old: profile to be replaced (NOT NULL) - * @new: profile to replace @old with (NOT NULL) - * - * Will duplicate and refcount elements that @new inherits from @old - * and will inherit @old children. - * - * refcount @new for list, put @old list refcount - * - * Requires: namespace list lock be held, or list not be shared - */ -static void __replace_profile(struct aa_profile *old, struct aa_profile *new) -{ - struct aa_policy *policy; - struct aa_profile *child, *tmp; - - if (old->parent) - policy = &old->parent->base; - else - policy = &old->ns->base; - - /* released when @new is freed */ - new->parent = aa_get_profile(old->parent); - new->ns = aa_get_namespace(old->ns); - __list_add_profile(&policy->profiles, new); - /* inherit children */ - list_for_each_entry_safe(child, tmp, &old->base.profiles, base.list) { - aa_put_profile(child->parent); - child->parent = aa_get_profile(new); - /* list refcount transferred to @new*/ - list_move(&child->base.list, &new->base.profiles); - } - - /* released by free_profile */ - old->replacedby = aa_get_profile(new); - __list_remove_profile(old); + list_del_rcu(&profile->base.list); + aa_put_profile(profile); } static void __profile_list_release(struct list_head *head); @@ -524,7 +461,8 @@ static void __remove_profile(struct aa_profile *profile) /* release any children lists first */ __profile_list_release(&profile->base.profiles); /* released by free_profile */ - profile->replacedby = aa_get_profile(profile->ns->unconfined); + __aa_update_replacedby(profile, profile->ns->unconfined); + __aa_fs_profile_rmdir(profile); __list_remove_profile(profile); } @@ -552,14 +490,17 @@ static void destroy_namespace(struct aa_namespace *ns) if (!ns) return; - write_lock(&ns->lock); + mutex_lock(&ns->lock); /* release all profiles in this namespace */ __profile_list_release(&ns->base.profiles); /* release all sub namespaces */ __ns_list_release(&ns->sub_ns); - write_unlock(&ns->lock); + if (ns->parent) + __aa_update_replacedby(ns->unconfined, ns->parent->unconfined); + __aa_fs_namespace_rmdir(ns); + mutex_unlock(&ns->lock); } /** @@ -570,25 +511,9 @@ static void destroy_namespace(struct aa_namespace *ns) */ static void __remove_namespace(struct aa_namespace *ns) { - struct aa_profile *unconfined = ns->unconfined; - /* remove ns from namespace list */ - list_del_init(&ns->base.list); - - /* - * break the ns, unconfined profile cyclic reference and forward - * all new unconfined profiles requests to the parent namespace - * This will result in all confined tasks that have a profile - * being removed, inheriting the parent->unconfined profile. - */ - if (ns->parent) - ns->unconfined = aa_get_profile(ns->parent->unconfined); - + list_del_rcu(&ns->base.list); destroy_namespace(ns); - - /* release original ns->unconfined ref */ - aa_put_profile(unconfined); - /* release ns->base.list ref, from removal above */ aa_put_namespace(ns); } @@ -634,8 +559,25 @@ void __init aa_free_root_ns(void) aa_put_namespace(ns); } + +static void free_replacedby(struct aa_replacedby *r) +{ + if (r) { + aa_put_profile(rcu_dereference(r->profile)); + kzfree(r); + } +} + + +void aa_free_replacedby_kref(struct kref *kref) +{ + struct aa_replacedby *r = container_of(kref, struct aa_replacedby, + count); + free_replacedby(r); +} + /** - * free_profile - free a profile + * aa_free_profile - free a profile * @profile: the profile to free (MAYBE NULL) * * Free a profile, its hats and null_profile. All references to the profile, @@ -644,25 +586,16 @@ void __init aa_free_root_ns(void) * If the profile was referenced from a task context, free_profile() will * be called from an rcu callback routine, so we must not sleep here. */ -static void free_profile(struct aa_profile *profile) +void aa_free_profile(struct aa_profile *profile) { - struct aa_profile *p; - AA_DEBUG("%s(%p)\n", __func__, profile); if (!profile) return; - if (!list_empty(&profile->base.list)) { - AA_ERROR("%s: internal error, " - "profile '%s' still on ns list\n", - __func__, profile->base.name); - BUG(); - } - /* free children profiles */ policy_destroy(&profile->base); - aa_put_profile(profile->parent); + aa_put_profile(rcu_access_pointer(profile->parent)); aa_put_namespace(profile->ns); kzfree(profile->rename); @@ -671,44 +604,35 @@ static void free_profile(struct aa_profile *profile) aa_free_cap_rules(&profile->caps); aa_free_rlimit_rules(&profile->rlimits); + kzfree(profile->dirname); aa_put_dfa(profile->xmatch); aa_put_dfa(profile->policy.dfa); - - /* put the profile reference for replacedby, but not via - * put_profile(kref_put). - * replacedby can form a long chain that can result in cascading - * frees that blows the stack because kref_put makes a nested fn - * call (it looks like recursion, with free_profile calling - * free_profile) for each profile in the chain lp#1056078. - */ - for (p = profile->replacedby; p; ) { - if (atomic_dec_and_test(&p->base.count.refcount)) { - /* no more refs on p, grab its replacedby */ - struct aa_profile *next = p->replacedby; - /* break the chain */ - p->replacedby = NULL; - /* now free p, chain is broken */ - free_profile(p); - - /* follow up with next profile in the chain */ - p = next; - } else - break; - } + aa_put_replacedby(profile->replacedby); kzfree(profile); } /** + * aa_free_profile_rcu - free aa_profile by rcu (called by aa_free_profile_kref) + * @head: rcu_head callback for freeing of a profile (NOT NULL) + */ +static void aa_free_profile_rcu(struct rcu_head *head) +{ + struct aa_profile *p = container_of(head, struct aa_profile, rcu); + if (p->flags & PFLAG_NS_COUNT) + free_namespace(p->ns); + else + aa_free_profile(p); +} + +/** * aa_free_profile_kref - free aa_profile by kref (called by aa_put_profile) * @kr: kref callback for freeing of a profile (NOT NULL) */ void aa_free_profile_kref(struct kref *kref) { - struct aa_profile *p = container_of(kref, struct aa_profile, - base.count); - - free_profile(p); + struct aa_profile *p = container_of(kref, struct aa_profile, count); + call_rcu(&p->rcu, aa_free_profile_rcu); } /** @@ -726,13 +650,23 @@ struct aa_profile *aa_alloc_profile(const char *hname) if (!profile) return NULL; - if (!policy_init(&profile->base, NULL, hname)) { - kzfree(profile); - return NULL; - } + profile->replacedby = kzalloc(sizeof(struct aa_replacedby), GFP_KERNEL); + if (!profile->replacedby) + goto fail; + kref_init(&profile->replacedby->count); + + if (!policy_init(&profile->base, NULL, hname)) + goto fail; + kref_init(&profile->count); /* refcount released by caller */ return profile; + +fail: + kzfree(profile->replacedby); + kzfree(profile); + + return NULL; } /** @@ -772,12 +706,12 @@ struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat) profile->flags |= PFLAG_HAT; /* released on free_profile */ - profile->parent = aa_get_profile(parent); + rcu_assign_pointer(profile->parent, aa_get_profile(parent)); profile->ns = aa_get_namespace(parent->ns); - write_lock(&profile->ns->lock); + mutex_lock(&profile->ns->lock); __list_add_profile(&parent->base.profiles, profile); - write_unlock(&profile->ns->lock); + mutex_unlock(&profile->ns->lock); /* refcount released by caller */ return profile; @@ -793,7 +727,7 @@ fail: * @head: list to search (NOT NULL) * @name: name of profile (NOT NULL) * - * Requires: ns lock protecting list be held + * Requires: rcu_read_lock be held * * Returns: unrefcounted profile ptr, or NULL if not found */ @@ -808,7 +742,7 @@ static struct aa_profile *__find_child(struct list_head *head, const char *name) * @name: name of profile (NOT NULL) * @len: length of @name substring to match * - * Requires: ns lock protecting list be held + * Requires: rcu_read_lock be held * * Returns: unrefcounted profile ptr, or NULL if not found */ @@ -829,9 +763,9 @@ struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name) { struct aa_profile *profile; - read_lock(&parent->ns->lock); + rcu_read_lock(); profile = aa_get_profile(__find_child(&parent->base.profiles, name)); - read_unlock(&parent->ns->lock); + rcu_read_unlock(); /* refcount released by caller */ return profile; @@ -846,7 +780,7 @@ struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name) * that matches hname does not need to exist, in general this * is used to load a new profile. * - * Requires: ns->lock be held + * Requires: rcu_read_lock be held * * Returns: unrefcounted policy or NULL if not found */ @@ -878,7 +812,7 @@ static struct aa_policy *__lookup_parent(struct aa_namespace *ns, * @base: base list to start looking up profile name from (NOT NULL) * @hname: hierarchical profile name (NOT NULL) * - * Requires: ns->lock be held + * Requires: rcu_read_lock be held * * Returns: unrefcounted profile pointer or NULL if not found * @@ -917,13 +851,15 @@ struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *hname) { struct aa_profile *profile; - read_lock(&ns->lock); - profile = aa_get_profile(__lookup_profile(&ns->base, hname)); - read_unlock(&ns->lock); + rcu_read_lock(); + do { + profile = __lookup_profile(&ns->base, hname); + } while (profile && !aa_get_profile_not0(profile)); + rcu_read_unlock(); /* the unconfined profile is not in the regular profile list */ if (!profile && strcmp(hname, "unconfined") == 0) - profile = aa_get_profile(ns->unconfined); + profile = aa_get_newest_profile(ns->unconfined); /* refcount released by caller */ return profile; @@ -953,25 +889,6 @@ static int replacement_allowed(struct aa_profile *profile, int noreplace, } /** - * __add_new_profile - simple wrapper around __list_add_profile - * @ns: namespace that profile is being added to (NOT NULL) - * @policy: the policy container to add the profile to (NOT NULL) - * @profile: profile to add (NOT NULL) - * - * add a profile to a list and do other required basic allocations - */ -static void __add_new_profile(struct aa_namespace *ns, struct aa_policy *policy, - struct aa_profile *profile) -{ - if (policy != &ns->base) - /* released on profile replacement or free_profile */ - profile->parent = aa_get_profile((struct aa_profile *) policy); - __list_add_profile(&policy->profiles, profile); - /* released on free_profile */ - profile->ns = aa_get_namespace(ns); -} - -/** * aa_audit_policy - Do auditing of policy changes * @op: policy operation being performed * @gfp: memory allocation flags @@ -1019,6 +936,121 @@ bool aa_may_manage_policy(int op) return 1; } +static struct aa_profile *__list_lookup_parent(struct list_head *lh, + struct aa_profile *profile) +{ + const char *base = hname_tail(profile->base.hname); + long len = base - profile->base.hname; + struct aa_load_ent *ent; + + /* parent won't have trailing // so remove from len */ + if (len <= 2) + return NULL; + len -= 2; + + list_for_each_entry(ent, lh, list) { + if (ent->new == profile) + continue; + if (strncmp(ent->new->base.hname, profile->base.hname, len) == + 0 && ent->new->base.hname[len] == 0) + return ent->new; + } + + return NULL; +} + +/** + * __replace_profile - replace @old with @new on a list + * @old: profile to be replaced (NOT NULL) + * @new: profile to replace @old with (NOT NULL) + * @share_replacedby: transfer @old->replacedby to @new + * + * Will duplicate and refcount elements that @new inherits from @old + * and will inherit @old children. + * + * refcount @new for list, put @old list refcount + * + * Requires: namespace list lock be held, or list not be shared + */ +static void __replace_profile(struct aa_profile *old, struct aa_profile *new, + bool share_replacedby) +{ + struct aa_profile *child, *tmp; + + if (!list_empty(&old->base.profiles)) { + LIST_HEAD(lh); + list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu); + + list_for_each_entry_safe(child, tmp, &lh, base.list) { + struct aa_profile *p; + + list_del_init(&child->base.list); + p = __find_child(&new->base.profiles, child->base.name); + if (p) { + /* @p replaces @child */ + __replace_profile(child, p, share_replacedby); + continue; + } + + /* inherit @child and its children */ + /* TODO: update hname of inherited children */ + /* list refcount transferred to @new */ + p = aa_deref_parent(child); + rcu_assign_pointer(child->parent, aa_get_profile(new)); + list_add_rcu(&child->base.list, &new->base.profiles); + aa_put_profile(p); + } + } + + if (!rcu_access_pointer(new->parent)) { + struct aa_profile *parent = aa_deref_parent(old); + rcu_assign_pointer(new->parent, aa_get_profile(parent)); + } + __aa_update_replacedby(old, new); + if (share_replacedby) { + aa_put_replacedby(new->replacedby); + new->replacedby = aa_get_replacedby(old->replacedby); + } else if (!rcu_access_pointer(new->replacedby->profile)) + /* aafs interface uses replacedby */ + rcu_assign_pointer(new->replacedby->profile, + aa_get_profile(new)); + __aa_fs_profile_migrate_dents(old, new); + + if (list_empty(&new->base.list)) { + /* new is not on a list already */ + list_replace_rcu(&old->base.list, &new->base.list); + aa_get_profile(new); + aa_put_profile(old); + } else + __list_remove_profile(old); +} + +/** + * __lookup_replace - lookup replacement information for a profile + * @ns - namespace the lookup occurs in + * @hname - name of profile to lookup + * @noreplace - true if not replacing an existing profile + * @p - Returns: profile to be replaced + * @info - Returns: info string on why lookup failed + * + * Returns: profile to replace (no ref) on success else ptr error + */ +static int __lookup_replace(struct aa_namespace *ns, const char *hname, + bool noreplace, struct aa_profile **p, + const char **info) +{ + *p = aa_get_profile(__lookup_profile(&ns->base, hname)); + if (*p) { + int error = replacement_allowed(*p, noreplace, info); + if (error) { + *info = "profile can not be replaced"; + return error; + } + } + + return 0; +} + /** * aa_replace_profiles - replace profile(s) on the profile list * @udata: serialized data stream (NOT NULL) @@ -1033,21 +1065,17 @@ bool aa_may_manage_policy(int op) */ ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace) { - struct aa_policy *policy; - struct aa_profile *old_profile = NULL, *new_profile = NULL; - struct aa_profile *rename_profile = NULL; - struct aa_namespace *ns = NULL; const char *ns_name, *name = NULL, *info = NULL; + struct aa_namespace *ns = NULL; + struct aa_load_ent *ent, *tmp; int op = OP_PROF_REPL; ssize_t error; + LIST_HEAD(lh); /* released below */ - new_profile = aa_unpack(udata, size, &ns_name); - if (IS_ERR(new_profile)) { - error = PTR_ERR(new_profile); - new_profile = NULL; - goto fail; - } + error = aa_unpack(udata, size, &lh, &ns_name); + if (error) + goto out; /* released below */ ns = aa_prepare_namespace(ns_name); @@ -1058,71 +1086,140 @@ ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace) goto fail; } - name = new_profile->base.hname; - - write_lock(&ns->lock); - /* no ref on policy only use inside lock */ - policy = __lookup_parent(ns, new_profile->base.hname); + mutex_lock(&ns->lock); + /* setup parent and ns info */ + list_for_each_entry(ent, &lh, list) { + struct aa_policy *policy; + + name = ent->new->base.hname; + error = __lookup_replace(ns, ent->new->base.hname, noreplace, + &ent->old, &info); + if (error) + goto fail_lock; + + if (ent->new->rename) { + error = __lookup_replace(ns, ent->new->rename, + noreplace, &ent->rename, + &info); + if (error) + goto fail_lock; + } - if (!policy) { - info = "parent does not exist"; - error = -ENOENT; - goto audit; + /* released when @new is freed */ + ent->new->ns = aa_get_namespace(ns); + + if (ent->old || ent->rename) + continue; + + /* no ref on policy only use inside lock */ + policy = __lookup_parent(ns, ent->new->base.hname); + if (!policy) { + struct aa_profile *p; + p = __list_lookup_parent(&lh, ent->new); + if (!p) { + error = -ENOENT; + info = "parent does not exist"; + name = ent->new->base.hname; + goto fail_lock; + } + rcu_assign_pointer(ent->new->parent, aa_get_profile(p)); + } else if (policy != &ns->base) { + /* released on profile replacement or free_profile */ + struct aa_profile *p = (struct aa_profile *) policy; + rcu_assign_pointer(ent->new->parent, aa_get_profile(p)); + } } - old_profile = __find_child(&policy->profiles, new_profile->base.name); - /* released below */ - aa_get_profile(old_profile); + /* create new fs entries for introspection if needed */ + list_for_each_entry(ent, &lh, list) { + if (ent->old) { + /* inherit old interface files */ - if (new_profile->rename) { - rename_profile = __lookup_profile(&ns->base, - new_profile->rename); - /* released below */ - aa_get_profile(rename_profile); + /* if (ent->rename) + TODO: support rename */ + /* } else if (ent->rename) { + TODO: support rename */ + } else { + struct dentry *parent; + if (rcu_access_pointer(ent->new->parent)) { + struct aa_profile *p; + p = aa_deref_parent(ent->new); + parent = prof_child_dir(p); + } else + parent = ns_subprofs_dir(ent->new->ns); + error = __aa_fs_profile_mkdir(ent->new, parent); + } - if (!rename_profile) { - info = "profile to rename does not exist"; - name = new_profile->rename; - error = -ENOENT; - goto audit; + if (error) { + info = "failed to create "; + goto fail_lock; } } - error = replacement_allowed(old_profile, noreplace, &info); - if (error) - goto audit; - - error = replacement_allowed(rename_profile, noreplace, &info); - if (error) - goto audit; - -audit: - if (!old_profile && !rename_profile) - op = OP_PROF_LOAD; - - error = audit_policy(op, GFP_ATOMIC, name, info, error); - - if (!error) { - if (rename_profile) - __replace_profile(rename_profile, new_profile); - if (old_profile) - __replace_profile(old_profile, new_profile); - if (!(old_profile || rename_profile)) - __add_new_profile(ns, policy, new_profile); + /* Done with checks that may fail - do actual replacement */ + list_for_each_entry_safe(ent, tmp, &lh, list) { + list_del_init(&ent->list); + op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL; + + audit_policy(op, GFP_ATOMIC, ent->new->base.name, NULL, error); + + if (ent->old) { + __replace_profile(ent->old, ent->new, 1); + if (ent->rename) { + /* aafs interface uses replacedby */ + struct aa_replacedby *r = ent->new->replacedby; + rcu_assign_pointer(r->profile, + aa_get_profile(ent->new)); + __replace_profile(ent->rename, ent->new, 0); + } + } else if (ent->rename) { + /* aafs interface uses replacedby */ + rcu_assign_pointer(ent->new->replacedby->profile, + aa_get_profile(ent->new)); + __replace_profile(ent->rename, ent->new, 0); + } else if (ent->new->parent) { + struct aa_profile *parent, *newest; + parent = aa_deref_parent(ent->new); + newest = aa_get_newest_profile(parent); + + /* parent replaced in this atomic set? */ + if (newest != parent) { + aa_get_profile(newest); + aa_put_profile(parent); + rcu_assign_pointer(ent->new->parent, newest); + } else + aa_put_profile(newest); + /* aafs interface uses replacedby */ + rcu_assign_pointer(ent->new->replacedby->profile, + aa_get_profile(ent->new)); + __list_add_profile(&parent->base.profiles, ent->new); + } else { + /* aafs interface uses replacedby */ + rcu_assign_pointer(ent->new->replacedby->profile, + aa_get_profile(ent->new)); + __list_add_profile(&ns->base.profiles, ent->new); + } + aa_load_ent_free(ent); } - write_unlock(&ns->lock); + mutex_unlock(&ns->lock); out: aa_put_namespace(ns); - aa_put_profile(rename_profile); - aa_put_profile(old_profile); - aa_put_profile(new_profile); + if (error) return error; return size; +fail_lock: + mutex_unlock(&ns->lock); fail: error = audit_policy(op, GFP_KERNEL, name, info, error); + + list_for_each_entry_safe(ent, tmp, &lh, list) { + list_del_init(&ent->list); + aa_load_ent_free(ent); + } + goto out; } @@ -1169,12 +1266,12 @@ ssize_t aa_remove_profiles(char *fqname, size_t size) if (!name) { /* remove namespace - can only happen if fqname[0] == ':' */ - write_lock(&ns->parent->lock); + mutex_lock(&ns->parent->lock); __remove_namespace(ns); - write_unlock(&ns->parent->lock); + mutex_unlock(&ns->parent->lock); } else { /* remove profile */ - write_lock(&ns->lock); + mutex_lock(&ns->lock); profile = aa_get_profile(__lookup_profile(&ns->base, name)); if (!profile) { error = -ENOENT; @@ -1183,7 +1280,7 @@ ssize_t aa_remove_profiles(char *fqname, size_t size) } name = profile->base.hname; __remove_profile(profile); - write_unlock(&ns->lock); + mutex_unlock(&ns->lock); } /* don't fail removal if audit fails */ @@ -1193,7 +1290,7 @@ ssize_t aa_remove_profiles(char *fqname, size_t size) return size; fail_ns_lock: - write_unlock(&ns->lock); + mutex_unlock(&ns->lock); aa_put_namespace(ns); fail: diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index 6dac7d7..a689f10 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -24,6 +24,7 @@ #include "include/apparmor.h" #include "include/audit.h" #include "include/context.h" +#include "include/crypto.h" #include "include/match.h" #include "include/policy.h" #include "include/policy_unpack.h" @@ -333,8 +334,10 @@ static struct aa_dfa *unpack_dfa(struct aa_ext *e) /* * The dfa is aligned with in the blob to 8 bytes * from the beginning of the stream. + * alignment adjust needed by dfa unpack */ - size_t sz = blob - (char *)e->start; + size_t sz = blob - (char *) e->start - + ((e->pos - e->start) & 7); size_t pad = ALIGN(sz, 8) - sz; int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) | TO_ACCEPT2_FLAG(YYTD_DATA32); @@ -490,6 +493,9 @@ static struct aa_profile *unpack_profile(struct aa_ext *e) /* profile renaming is optional */ (void) unpack_str(e, &profile->rename, "rename"); + /* attachment string is optional */ + (void) unpack_str(e, &profile->attach, "attach"); + /* xmatch is optional and may be NULL */ profile->xmatch = unpack_dfa(e); if (IS_ERR(profile->xmatch)) { @@ -509,12 +515,16 @@ static struct aa_profile *unpack_profile(struct aa_ext *e) goto fail; if (!unpack_u32(e, &tmp, NULL)) goto fail; - if (tmp) + if (tmp & PACKED_FLAG_HAT) profile->flags |= PFLAG_HAT; if (!unpack_u32(e, &tmp, NULL)) goto fail; - if (tmp) + if (tmp == PACKED_MODE_COMPLAIN) profile->mode = APPARMOR_COMPLAIN; + else if (tmp == PACKED_MODE_KILL) + profile->mode = APPARMOR_KILL; + else if (tmp == PACKED_MODE_UNCONFINED) + profile->mode = APPARMOR_UNCONFINED; if (!unpack_u32(e, &tmp, NULL)) goto fail; if (tmp) @@ -614,7 +624,7 @@ fail: else if (!name) name = "unknown"; audit_iface(profile, name, "failed to unpack profile", e, error); - aa_put_profile(profile); + aa_free_profile(profile); return ERR_PTR(error); } @@ -622,29 +632,41 @@ fail: /** * verify_head - unpack serialized stream header * @e: serialized data read head (NOT NULL) + * @required: whether the header is required or optional * @ns: Returns - namespace if one is specified else NULL (NOT NULL) * * Returns: error or 0 if header is good */ -static int verify_header(struct aa_ext *e, const char **ns) +static int verify_header(struct aa_ext *e, int required, const char **ns) { int error = -EPROTONOSUPPORT; + const char *name = NULL; + *ns = NULL; + /* get the interface version */ if (!unpack_u32(e, &e->version, "version")) { - audit_iface(NULL, NULL, "invalid profile format", e, error); - return error; - } + if (required) { + audit_iface(NULL, NULL, "invalid profile format", e, + error); + return error; + } - /* check that the interface version is currently supported */ - if (e->version != 5) { - audit_iface(NULL, NULL, "unsupported interface version", e, - error); - return error; + /* check that the interface version is currently supported */ + if (e->version != 5) { + audit_iface(NULL, NULL, "unsupported interface version", + e, error); + return error; + } } + /* read the namespace if present */ - if (!unpack_str(e, ns, "namespace")) - *ns = NULL; + if (unpack_str(e, &name, "namespace")) { + if (*ns && strcmp(*ns, name)) + audit_iface(NULL, NULL, "invalid ns change", e, error); + else if (!*ns) + *ns = name; + } return 0; } @@ -693,18 +715,40 @@ static int verify_profile(struct aa_profile *profile) return 0; } +void aa_load_ent_free(struct aa_load_ent *ent) +{ + if (ent) { + aa_put_profile(ent->rename); + aa_put_profile(ent->old); + aa_put_profile(ent->new); + kzfree(ent); + } +} + +struct aa_load_ent *aa_load_ent_alloc(void) +{ + struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL); + if (ent) + INIT_LIST_HEAD(&ent->list); + return ent; +} + /** - * aa_unpack - unpack packed binary profile data loaded from user space + * aa_unpack - unpack packed binary profile(s) data loaded from user space * @udata: user data copied to kmem (NOT NULL) * @size: the size of the user data + * @lh: list to place unpacked profiles in a aa_repl_ws * @ns: Returns namespace profile is in if specified else NULL (NOT NULL) * - * Unpack user data and return refcounted allocated profile or ERR_PTR + * Unpack user data and return refcounted allocated profile(s) stored in + * @lh in order of discovery, with the list chain stored in base.list + * or error * - * Returns: profile else error pointer if fails to unpack + * Returns: profile(s) on @lh else error pointer if fails to unpack */ -struct aa_profile *aa_unpack(void *udata, size_t size, const char **ns) +int aa_unpack(void *udata, size_t size, struct list_head *lh, const char **ns) { + struct aa_load_ent *tmp, *ent; struct aa_profile *profile = NULL; int error; struct aa_ext e = { @@ -713,20 +757,49 @@ struct aa_profile *aa_unpack(void *udata, size_t size, const char **ns) .pos = udata, }; - error = verify_header(&e, ns); - if (error) - return ERR_PTR(error); + *ns = NULL; + while (e.pos < e.end) { + void *start; + error = verify_header(&e, e.pos == e.start, ns); + if (error) + goto fail; + + start = e.pos; + profile = unpack_profile(&e); + if (IS_ERR(profile)) { + error = PTR_ERR(profile); + goto fail; + } + + error = verify_profile(profile); + if (error) + goto fail_profile; + + error = aa_calc_profile_hash(profile, e.version, start, + e.pos - start); + if (error) + goto fail_profile; + + ent = aa_load_ent_alloc(); + if (!ent) { + error = -ENOMEM; + goto fail_profile; + } + + ent->new = profile; + list_add_tail(&ent->list, lh); + } + + return 0; - profile = unpack_profile(&e); - if (IS_ERR(profile)) - return profile; +fail_profile: + aa_put_profile(profile); - error = verify_profile(profile); - if (error) { - aa_put_profile(profile); - profile = ERR_PTR(error); +fail: + list_for_each_entry_safe(ent, tmp, lh, list) { + list_del_init(&ent->list); + aa_load_ent_free(ent); } - /* return refcount */ - return profile; + return error; } diff --git a/security/apparmor/procattr.c b/security/apparmor/procattr.c index 6c93901..b125acc 100644 --- a/security/apparmor/procattr.c +++ b/security/apparmor/procattr.c @@ -37,7 +37,7 @@ int aa_getprocattr(struct aa_profile *profile, char **string) { char *str; int len = 0, mode_len = 0, ns_len = 0, name_len; - const char *mode_str = profile_mode_names[profile->mode]; + const char *mode_str = aa_profile_mode_names[profile->mode]; const char *ns_name = NULL; struct aa_namespace *ns = profile->ns; struct aa_namespace *current_ns = __aa_current_profile()->ns; diff --git a/security/capability.c b/security/capability.c index b6d779b..8b4f24a 100644 --- a/security/capability.c +++ b/security/capability.c @@ -129,7 +129,7 @@ static void cap_inode_free_security(struct inode *inode) } static int cap_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, char **name, + const struct qstr *qstr, const char **name, void **value, size_t *len) { return -EOPNOTSUPP; diff --git a/security/commoncap.c b/security/commoncap.c index c44b6fe..b9d613e 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -768,16 +768,16 @@ int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags) */ static int cap_safe_nice(struct task_struct *p) { - int is_subset; + int is_subset, ret = 0; rcu_read_lock(); is_subset = cap_issubset(__task_cred(p)->cap_permitted, current_cred()->cap_permitted); + if (!is_subset && !ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) + ret = -EPERM; rcu_read_unlock(); - if (!is_subset && !capable(CAP_SYS_NICE)) - return -EPERM; - return 0; + return ret; } /** @@ -824,7 +824,7 @@ int cap_task_setnice(struct task_struct *p, int nice) */ static long cap_prctl_drop(struct cred *new, unsigned long cap) { - if (!capable(CAP_SETPCAP)) + if (!ns_capable(current_user_ns(), CAP_SETPCAP)) return -EPERM; if (!cap_valid(cap)) return -EINVAL; diff --git a/security/device_cgroup.c b/security/device_cgroup.c index e8aad69..c123628 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -53,22 +53,17 @@ struct dev_cgroup { static inline struct dev_cgroup *css_to_devcgroup(struct cgroup_subsys_state *s) { - return container_of(s, struct dev_cgroup, css); -} - -static inline struct dev_cgroup *cgroup_to_devcgroup(struct cgroup *cgroup) -{ - return css_to_devcgroup(cgroup_subsys_state(cgroup, devices_subsys_id)); + return s ? container_of(s, struct dev_cgroup, css) : NULL; } static inline struct dev_cgroup *task_devcgroup(struct task_struct *task) { - return css_to_devcgroup(task_subsys_state(task, devices_subsys_id)); + return css_to_devcgroup(task_css(task, devices_subsys_id)); } struct cgroup_subsys devices_subsys; -static int devcgroup_can_attach(struct cgroup *new_cgrp, +static int devcgroup_can_attach(struct cgroup_subsys_state *new_css, struct cgroup_taskset *set) { struct task_struct *task = cgroup_taskset_first(set); @@ -193,18 +188,16 @@ static inline bool is_devcg_online(const struct dev_cgroup *devcg) /** * devcgroup_online - initializes devcgroup's behavior and exceptions based on * parent's - * @cgroup: cgroup getting online + * @css: css getting online * returns 0 in case of success, error code otherwise */ -static int devcgroup_online(struct cgroup *cgroup) +static int devcgroup_online(struct cgroup_subsys_state *css) { - struct dev_cgroup *dev_cgroup, *parent_dev_cgroup = NULL; + struct dev_cgroup *dev_cgroup = css_to_devcgroup(css); + struct dev_cgroup *parent_dev_cgroup = css_to_devcgroup(css_parent(css)); int ret = 0; mutex_lock(&devcgroup_mutex); - dev_cgroup = cgroup_to_devcgroup(cgroup); - if (cgroup->parent) - parent_dev_cgroup = cgroup_to_devcgroup(cgroup->parent); if (parent_dev_cgroup == NULL) dev_cgroup->behavior = DEVCG_DEFAULT_ALLOW; @@ -219,9 +212,9 @@ static int devcgroup_online(struct cgroup *cgroup) return ret; } -static void devcgroup_offline(struct cgroup *cgroup) +static void devcgroup_offline(struct cgroup_subsys_state *css) { - struct dev_cgroup *dev_cgroup = cgroup_to_devcgroup(cgroup); + struct dev_cgroup *dev_cgroup = css_to_devcgroup(css); mutex_lock(&devcgroup_mutex); dev_cgroup->behavior = DEVCG_DEFAULT_NONE; @@ -231,7 +224,8 @@ static void devcgroup_offline(struct cgroup *cgroup) /* * called from kernel/cgroup.c with cgroup_lock() held. */ -static struct cgroup_subsys_state *devcgroup_css_alloc(struct cgroup *cgroup) +static struct cgroup_subsys_state * +devcgroup_css_alloc(struct cgroup_subsys_state *parent_css) { struct dev_cgroup *dev_cgroup; @@ -244,11 +238,10 @@ static struct cgroup_subsys_state *devcgroup_css_alloc(struct cgroup *cgroup) return &dev_cgroup->css; } -static void devcgroup_css_free(struct cgroup *cgroup) +static void devcgroup_css_free(struct cgroup_subsys_state *css) { - struct dev_cgroup *dev_cgroup; + struct dev_cgroup *dev_cgroup = css_to_devcgroup(css); - dev_cgroup = cgroup_to_devcgroup(cgroup); __dev_exception_clean(dev_cgroup); kfree(dev_cgroup); } @@ -291,10 +284,10 @@ static void set_majmin(char *str, unsigned m) sprintf(str, "%u", m); } -static int devcgroup_seq_read(struct cgroup *cgroup, struct cftype *cft, - struct seq_file *m) +static int devcgroup_seq_read(struct cgroup_subsys_state *css, + struct cftype *cft, struct seq_file *m) { - struct dev_cgroup *devcgroup = cgroup_to_devcgroup(cgroup); + struct dev_cgroup *devcgroup = css_to_devcgroup(css); struct dev_exception_item *ex; char maj[MAJMINLEN], min[MAJMINLEN], acc[ACCLEN]; @@ -394,12 +387,10 @@ static bool may_access(struct dev_cgroup *dev_cgroup, static int parent_has_perm(struct dev_cgroup *childcg, struct dev_exception_item *ex) { - struct cgroup *pcg = childcg->css.cgroup->parent; - struct dev_cgroup *parent; + struct dev_cgroup *parent = css_to_devcgroup(css_parent(&childcg->css)); - if (!pcg) + if (!parent) return 1; - parent = cgroup_to_devcgroup(pcg); return may_access(parent, ex, childcg->behavior); } @@ -451,13 +442,13 @@ static void revalidate_active_exceptions(struct dev_cgroup *devcg) static int propagate_exception(struct dev_cgroup *devcg_root, struct dev_exception_item *ex) { - struct cgroup *root = devcg_root->css.cgroup, *pos; + struct cgroup_subsys_state *pos; int rc = 0; rcu_read_lock(); - cgroup_for_each_descendant_pre(pos, root) { - struct dev_cgroup *devcg = cgroup_to_devcgroup(pos); + css_for_each_descendant_pre(pos, &devcg_root->css) { + struct dev_cgroup *devcg = css_to_devcgroup(pos); /* * Because devcgroup_mutex is held, no devcg will become @@ -465,7 +456,7 @@ static int propagate_exception(struct dev_cgroup *devcg_root, * methods), and online ones are safe to access outside RCU * read lock without bumping refcnt. */ - if (!is_devcg_online(devcg)) + if (pos == &devcg_root->css || !is_devcg_online(devcg)) continue; rcu_read_unlock(); @@ -524,15 +515,11 @@ static int devcgroup_update_access(struct dev_cgroup *devcgroup, char temp[12]; /* 11 + 1 characters needed for a u32 */ int count, rc = 0; struct dev_exception_item ex; - struct cgroup *p = devcgroup->css.cgroup; - struct dev_cgroup *parent = NULL; + struct dev_cgroup *parent = css_to_devcgroup(css_parent(&devcgroup->css)); if (!capable(CAP_SYS_ADMIN)) return -EPERM; - if (p->parent) - parent = cgroup_to_devcgroup(p->parent); - memset(&ex, 0, sizeof(ex)); b = buffer; @@ -677,13 +664,13 @@ static int devcgroup_update_access(struct dev_cgroup *devcgroup, return rc; } -static int devcgroup_access_write(struct cgroup *cgrp, struct cftype *cft, - const char *buffer) +static int devcgroup_access_write(struct cgroup_subsys_state *css, + struct cftype *cft, const char *buffer) { int retval; mutex_lock(&devcgroup_mutex); - retval = devcgroup_update_access(cgroup_to_devcgroup(cgrp), + retval = devcgroup_update_access(css_to_devcgroup(css), cft->private, buffer); mutex_unlock(&devcgroup_mutex); return retval; diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index df0fa45..af9b685 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -418,7 +418,7 @@ int evm_inode_init_security(struct inode *inode, evm_xattr->value = xattr_data; evm_xattr->value_len = sizeof(*xattr_data); - evm_xattr->name = kstrdup(XATTR_EVM_SUFFIX, GFP_NOFS); + evm_xattr->name = XATTR_EVM_SUFFIX; return 0; out: kfree(xattr_data); diff --git a/security/keys/Kconfig b/security/keys/Kconfig index a90d6d30..53d8748 100644 --- a/security/keys/Kconfig +++ b/security/keys/Kconfig @@ -4,6 +4,7 @@ config KEYS bool "Enable access key retention support" + select ASSOCIATIVE_ARRAY help This option provides support for retaining authentication tokens and access keys in the kernel. @@ -19,6 +20,34 @@ config KEYS If you are unsure as to whether this is required, answer N. +config PERSISTENT_KEYRINGS + bool "Enable register of persistent per-UID keyrings" + depends on KEYS + help + This option provides a register of persistent per-UID keyrings, + primarily aimed at Kerberos key storage. The keyrings are persistent + in the sense that they stay around after all processes of that UID + have exited, not that they survive the machine being rebooted. + + A particular keyring may be accessed by either the user whose keyring + it is or by a process with administrative privileges. The active + LSMs gets to rule on which admin-level processes get to access the + cache. + + Keyrings are created and added into the register upon demand and get + removed if they expire (a default timeout is set upon creation). + +config BIG_KEYS + tristate "Large payload keys" + depends on KEYS + depends on TMPFS + help + This option provides support for holding large keys within the kernel + (for example Kerberos ticket caches). The data may be stored out to + swapspace by tmpfs. + + If you are unsure as to whether this is required, answer N. + config TRUSTED_KEYS tristate "TRUSTED KEYS" depends on KEYS && TCG_TPM diff --git a/security/keys/Makefile b/security/keys/Makefile index 504aaa0..dfb3a7b 100644 --- a/security/keys/Makefile +++ b/security/keys/Makefile @@ -18,9 +18,11 @@ obj-y := \ obj-$(CONFIG_KEYS_COMPAT) += compat.o obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_SYSCTL) += sysctl.o +obj-$(CONFIG_PERSISTENT_KEYRINGS) += persistent.o # # Key types # +obj-$(CONFIG_BIG_KEYS) += big_key.o obj-$(CONFIG_TRUSTED_KEYS) += trusted.o obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys/ diff --git a/security/keys/big_key.c b/security/keys/big_key.c new file mode 100644 index 0000000..5f9defc --- /dev/null +++ b/security/keys/big_key.c @@ -0,0 +1,204 @@ +/* Large capacity key type + * + * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/seq_file.h> +#include <linux/file.h> +#include <linux/shmem_fs.h> +#include <linux/err.h> +#include <keys/user-type.h> +#include <keys/big_key-type.h> + +MODULE_LICENSE("GPL"); + +/* + * If the data is under this limit, there's no point creating a shm file to + * hold it as the permanently resident metadata for the shmem fs will be at + * least as large as the data. + */ +#define BIG_KEY_FILE_THRESHOLD (sizeof(struct inode) + sizeof(struct dentry)) + +/* + * big_key defined keys take an arbitrary string as the description and an + * arbitrary blob of data as the payload + */ +struct key_type key_type_big_key = { + .name = "big_key", + .def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, + .instantiate = big_key_instantiate, + .match = user_match, + .revoke = big_key_revoke, + .destroy = big_key_destroy, + .describe = big_key_describe, + .read = big_key_read, +}; + +/* + * Instantiate a big key + */ +int big_key_instantiate(struct key *key, struct key_preparsed_payload *prep) +{ + struct path *path = (struct path *)&key->payload.data2; + struct file *file; + ssize_t written; + size_t datalen = prep->datalen; + int ret; + + ret = -EINVAL; + if (datalen <= 0 || datalen > 1024 * 1024 || !prep->data) + goto error; + + /* Set an arbitrary quota */ + ret = key_payload_reserve(key, 16); + if (ret < 0) + goto error; + + key->type_data.x[1] = datalen; + + if (datalen > BIG_KEY_FILE_THRESHOLD) { + /* Create a shmem file to store the data in. This will permit the data + * to be swapped out if needed. + * + * TODO: Encrypt the stored data with a temporary key. + */ + file = shmem_file_setup("", datalen, 0); + if (IS_ERR(file)) + goto err_quota; + + written = kernel_write(file, prep->data, prep->datalen, 0); + if (written != datalen) { + if (written >= 0) + ret = -ENOMEM; + goto err_fput; + } + + /* Pin the mount and dentry to the key so that we can open it again + * later + */ + *path = file->f_path; + path_get(path); + fput(file); + } else { + /* Just store the data in a buffer */ + void *data = kmalloc(datalen, GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto err_quota; + } + + key->payload.data = memcpy(data, prep->data, prep->datalen); + } + return 0; + +err_fput: + fput(file); +err_quota: + key_payload_reserve(key, 0); +error: + return ret; +} + +/* + * dispose of the links from a revoked keyring + * - called with the key sem write-locked + */ +void big_key_revoke(struct key *key) +{ + struct path *path = (struct path *)&key->payload.data2; + + /* clear the quota */ + key_payload_reserve(key, 0); + if (key_is_instantiated(key) && key->type_data.x[1] > BIG_KEY_FILE_THRESHOLD) + vfs_truncate(path, 0); +} + +/* + * dispose of the data dangling from the corpse of a big_key key + */ +void big_key_destroy(struct key *key) +{ + if (key->type_data.x[1] > BIG_KEY_FILE_THRESHOLD) { + struct path *path = (struct path *)&key->payload.data2; + path_put(path); + path->mnt = NULL; + path->dentry = NULL; + } else { + kfree(key->payload.data); + key->payload.data = NULL; + } +} + +/* + * describe the big_key key + */ +void big_key_describe(const struct key *key, struct seq_file *m) +{ + unsigned long datalen = key->type_data.x[1]; + + seq_puts(m, key->description); + + if (key_is_instantiated(key)) + seq_printf(m, ": %lu [%s]", + datalen, + datalen > BIG_KEY_FILE_THRESHOLD ? "file" : "buff"); +} + +/* + * read the key data + * - the key's semaphore is read-locked + */ +long big_key_read(const struct key *key, char __user *buffer, size_t buflen) +{ + unsigned long datalen = key->type_data.x[1]; + long ret; + + if (!buffer || buflen < datalen) + return datalen; + + if (datalen > BIG_KEY_FILE_THRESHOLD) { + struct path *path = (struct path *)&key->payload.data2; + struct file *file; + loff_t pos; + + file = dentry_open(path, O_RDONLY, current_cred()); + if (IS_ERR(file)) + return PTR_ERR(file); + + pos = 0; + ret = vfs_read(file, buffer, datalen, &pos); + fput(file); + if (ret >= 0 && ret != datalen) + ret = -EIO; + } else { + ret = datalen; + if (copy_to_user(buffer, key->payload.data, datalen) != 0) + ret = -EFAULT; + } + + return ret; +} + +/* + * Module stuff + */ +static int __init big_key_init(void) +{ + return register_key_type(&key_type_big_key); +} + +static void __exit big_key_cleanup(void) +{ + unregister_key_type(&key_type_big_key); +} + +module_init(big_key_init); +module_exit(big_key_cleanup); diff --git a/security/keys/compat.c b/security/keys/compat.c index d65fa7f..bbd32c7 100644 --- a/security/keys/compat.c +++ b/security/keys/compat.c @@ -138,6 +138,9 @@ asmlinkage long compat_sys_keyctl(u32 option, case KEYCTL_INVALIDATE: return keyctl_invalidate_key(arg2); + case KEYCTL_GET_PERSISTENT: + return keyctl_get_persistent(arg2, arg3); + default: return -EOPNOTSUPP; } diff --git a/security/keys/gc.c b/security/keys/gc.c index d67c97b..cce621c 100644 --- a/security/keys/gc.c +++ b/security/keys/gc.c @@ -130,6 +130,13 @@ void key_gc_keytype(struct key_type *ktype) kleave(""); } +static int key_gc_keyring_func(const void *object, void *iterator_data) +{ + const struct key *key = object; + time_t *limit = iterator_data; + return key_is_dead(key, *limit); +} + /* * Garbage collect pointers from a keyring. * @@ -138,10 +145,9 @@ void key_gc_keytype(struct key_type *ktype) */ static void key_gc_keyring(struct key *keyring, time_t limit) { - struct keyring_list *klist; - int loop; + int result; - kenter("%x", key_serial(keyring)); + kenter("%x{%s}", keyring->serial, keyring->description ?: ""); if (keyring->flags & ((1 << KEY_FLAG_INVALIDATED) | (1 << KEY_FLAG_REVOKED))) @@ -149,27 +155,17 @@ static void key_gc_keyring(struct key *keyring, time_t limit) /* scan the keyring looking for dead keys */ rcu_read_lock(); - klist = rcu_dereference(keyring->payload.subscriptions); - if (!klist) - goto unlock_dont_gc; - - loop = klist->nkeys; - smp_rmb(); - for (loop--; loop >= 0; loop--) { - struct key *key = rcu_dereference(klist->keys[loop]); - if (key_is_dead(key, limit)) - goto do_gc; - } - -unlock_dont_gc: + result = assoc_array_iterate(&keyring->keys, + key_gc_keyring_func, &limit); rcu_read_unlock(); + if (result == true) + goto do_gc; + dont_gc: kleave(" [no gc]"); return; do_gc: - rcu_read_unlock(); - keyring_gc(keyring, limit); kleave(" [gc]"); } @@ -392,7 +388,6 @@ found_unreferenced_key: */ found_keyring: spin_unlock(&key_serial_lock); - kdebug("scan keyring %d", key->serial); key_gc_keyring(key, limit); goto maybe_resched; diff --git a/security/keys/internal.h b/security/keys/internal.h index d4f1468..80b2aac 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -89,42 +89,53 @@ extern struct key_type *key_type_lookup(const char *type); extern void key_type_put(struct key_type *ktype); extern int __key_link_begin(struct key *keyring, - const struct key_type *type, - const char *description, - unsigned long *_prealloc); + const struct keyring_index_key *index_key, + struct assoc_array_edit **_edit); extern int __key_link_check_live_key(struct key *keyring, struct key *key); -extern void __key_link(struct key *keyring, struct key *key, - unsigned long *_prealloc); +extern void __key_link(struct key *key, struct assoc_array_edit **_edit); extern void __key_link_end(struct key *keyring, - struct key_type *type, - unsigned long prealloc); + const struct keyring_index_key *index_key, + struct assoc_array_edit *edit); -extern key_ref_t __keyring_search_one(key_ref_t keyring_ref, - const struct key_type *type, - const char *description, - key_perm_t perm); +extern key_ref_t find_key_to_update(key_ref_t keyring_ref, + const struct keyring_index_key *index_key); extern struct key *keyring_search_instkey(struct key *keyring, key_serial_t target_id); +extern int iterate_over_keyring(const struct key *keyring, + int (*func)(const struct key *key, void *data), + void *data); + typedef int (*key_match_func_t)(const struct key *, const void *); +struct keyring_search_context { + struct keyring_index_key index_key; + const struct cred *cred; + key_match_func_t match; + const void *match_data; + unsigned flags; +#define KEYRING_SEARCH_LOOKUP_TYPE 0x0001 /* [as type->def_lookup_type] */ +#define KEYRING_SEARCH_NO_STATE_CHECK 0x0002 /* Skip state checks */ +#define KEYRING_SEARCH_DO_STATE_CHECK 0x0004 /* Override NO_STATE_CHECK */ +#define KEYRING_SEARCH_NO_UPDATE_TIME 0x0008 /* Don't update times */ +#define KEYRING_SEARCH_NO_CHECK_PERM 0x0010 /* Don't check permissions */ +#define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0020 /* Give an error on excessive depth */ + + int (*iterator)(const void *object, void *iterator_data); + + /* Internal stuff */ + int skipped_ret; + bool possessed; + key_ref_t result; + struct timespec now; +}; + extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, - const struct cred *cred, - struct key_type *type, - const void *description, - key_match_func_t match, - bool no_state_check); - -extern key_ref_t search_my_process_keyrings(struct key_type *type, - const void *description, - key_match_func_t match, - bool no_state_check, - const struct cred *cred); -extern key_ref_t search_process_keyrings(struct key_type *type, - const void *description, - key_match_func_t match, - const struct cred *cred); + struct keyring_search_context *ctx); + +extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx); +extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx); extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check); @@ -202,7 +213,7 @@ extern struct key *key_get_instantiation_authkey(key_serial_t target_id); /* * Determine whether a key is dead. */ -static inline bool key_is_dead(struct key *key, time_t limit) +static inline bool key_is_dead(const struct key *key, time_t limit) { return key->flags & ((1 << KEY_FLAG_DEAD) | @@ -244,6 +255,15 @@ extern long keyctl_invalidate_key(key_serial_t); extern long keyctl_instantiate_key_common(key_serial_t, const struct iovec *, unsigned, size_t, key_serial_t); +#ifdef CONFIG_PERSISTENT_KEYRINGS +extern long keyctl_get_persistent(uid_t, key_serial_t); +extern unsigned persistent_keyring_expiry; +#else +static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring) +{ + return -EOPNOTSUPP; +} +#endif /* * Debugging key validation diff --git a/security/keys/key.c b/security/keys/key.c index 8fb7c7b..d331ea9 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -242,8 +242,8 @@ struct key *key_alloc(struct key_type *type, const char *desc, } } - desclen = strlen(desc) + 1; - quotalen = desclen + type->def_datalen; + desclen = strlen(desc); + quotalen = desclen + 1 + type->def_datalen; /* get hold of the key tracking for this user */ user = key_user_lookup(uid); @@ -277,7 +277,8 @@ struct key *key_alloc(struct key_type *type, const char *desc, goto no_memory_2; if (desc) { - key->description = kmemdup(desc, desclen, GFP_KERNEL); + key->index_key.desc_len = desclen; + key->index_key.description = kmemdup(desc, desclen + 1, GFP_KERNEL); if (!key->description) goto no_memory_3; } @@ -285,7 +286,7 @@ struct key *key_alloc(struct key_type *type, const char *desc, atomic_set(&key->usage, 1); init_rwsem(&key->sem); lockdep_set_class(&key->sem, &type->lock_class); - key->type = type; + key->index_key.type = type; key->user = user; key->quotalen = quotalen; key->datalen = type->def_datalen; @@ -299,6 +300,8 @@ struct key *key_alloc(struct key_type *type, const char *desc, if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) key->flags |= 1 << KEY_FLAG_IN_QUOTA; + if (flags & KEY_ALLOC_TRUSTED) + key->flags |= 1 << KEY_FLAG_TRUSTED; memset(&key->type_data, 0, sizeof(key->type_data)); @@ -408,7 +411,7 @@ static int __key_instantiate_and_link(struct key *key, struct key_preparsed_payload *prep, struct key *keyring, struct key *authkey, - unsigned long *_prealloc) + struct assoc_array_edit **_edit) { int ret, awaken; @@ -435,7 +438,7 @@ static int __key_instantiate_and_link(struct key *key, /* and link it into the destination keyring */ if (keyring) - __key_link(keyring, key, _prealloc); + __key_link(key, _edit); /* disable the authorisation key */ if (authkey) @@ -475,7 +478,7 @@ int key_instantiate_and_link(struct key *key, struct key *authkey) { struct key_preparsed_payload prep; - unsigned long prealloc; + struct assoc_array_edit *edit; int ret; memset(&prep, 0, sizeof(prep)); @@ -489,17 +492,15 @@ int key_instantiate_and_link(struct key *key, } if (keyring) { - ret = __key_link_begin(keyring, key->type, key->description, - &prealloc); + ret = __key_link_begin(keyring, &key->index_key, &edit); if (ret < 0) goto error_free_preparse; } - ret = __key_instantiate_and_link(key, &prep, keyring, authkey, - &prealloc); + ret = __key_instantiate_and_link(key, &prep, keyring, authkey, &edit); if (keyring) - __key_link_end(keyring, key->type, prealloc); + __key_link_end(keyring, &key->index_key, edit); error_free_preparse: if (key->type->preparse) @@ -537,7 +538,7 @@ int key_reject_and_link(struct key *key, struct key *keyring, struct key *authkey) { - unsigned long prealloc; + struct assoc_array_edit *edit; struct timespec now; int ret, awaken, link_ret = 0; @@ -548,8 +549,7 @@ int key_reject_and_link(struct key *key, ret = -EBUSY; if (keyring) - link_ret = __key_link_begin(keyring, key->type, - key->description, &prealloc); + link_ret = __key_link_begin(keyring, &key->index_key, &edit); mutex_lock(&key_construction_mutex); @@ -571,7 +571,7 @@ int key_reject_and_link(struct key *key, /* and link it into the destination keyring */ if (keyring && link_ret == 0) - __key_link(keyring, key, &prealloc); + __key_link(key, &edit); /* disable the authorisation key */ if (authkey) @@ -581,7 +581,7 @@ int key_reject_and_link(struct key *key, mutex_unlock(&key_construction_mutex); if (keyring) - __key_link_end(keyring, key->type, prealloc); + __key_link_end(keyring, &key->index_key, edit); /* wake up anyone waiting for a key to be constructed */ if (awaken) @@ -645,7 +645,7 @@ found: /* this races with key_put(), but that doesn't matter since key_put() * doesn't actually change the key */ - atomic_inc(&key->usage); + __key_get(key); error: spin_unlock(&key_serial_lock); @@ -780,25 +780,27 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, key_perm_t perm, unsigned long flags) { - unsigned long prealloc; + struct keyring_index_key index_key = { + .description = description, + }; struct key_preparsed_payload prep; + struct assoc_array_edit *edit; const struct cred *cred = current_cred(); - struct key_type *ktype; struct key *keyring, *key = NULL; key_ref_t key_ref; int ret; /* look up the key type to see if it's one of the registered kernel * types */ - ktype = key_type_lookup(type); - if (IS_ERR(ktype)) { + index_key.type = key_type_lookup(type); + if (IS_ERR(index_key.type)) { key_ref = ERR_PTR(-ENODEV); goto error; } key_ref = ERR_PTR(-EINVAL); - if (!ktype->match || !ktype->instantiate || - (!description && !ktype->preparse)) + if (!index_key.type->match || !index_key.type->instantiate || + (!index_key.description && !index_key.type->preparse)) goto error_put_type; keyring = key_ref_to_ptr(keyring_ref); @@ -812,21 +814,28 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, memset(&prep, 0, sizeof(prep)); prep.data = payload; prep.datalen = plen; - prep.quotalen = ktype->def_datalen; - if (ktype->preparse) { - ret = ktype->preparse(&prep); + prep.quotalen = index_key.type->def_datalen; + prep.trusted = flags & KEY_ALLOC_TRUSTED; + if (index_key.type->preparse) { + ret = index_key.type->preparse(&prep); if (ret < 0) { key_ref = ERR_PTR(ret); goto error_put_type; } - if (!description) - description = prep.description; + if (!index_key.description) + index_key.description = prep.description; key_ref = ERR_PTR(-EINVAL); - if (!description) + if (!index_key.description) goto error_free_prep; } + index_key.desc_len = strlen(index_key.description); + + key_ref = ERR_PTR(-EPERM); + if (!prep.trusted && test_bit(KEY_FLAG_TRUSTED_ONLY, &keyring->flags)) + goto error_free_prep; + flags |= prep.trusted ? KEY_ALLOC_TRUSTED : 0; - ret = __key_link_begin(keyring, ktype, description, &prealloc); + ret = __key_link_begin(keyring, &index_key, &edit); if (ret < 0) { key_ref = ERR_PTR(ret); goto error_free_prep; @@ -844,10 +853,9 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, * key of the same type and description in the destination keyring and * update that instead if possible */ - if (ktype->update) { - key_ref = __keyring_search_one(keyring_ref, ktype, description, - 0); - if (!IS_ERR(key_ref)) + if (index_key.type->update) { + key_ref = find_key_to_update(keyring_ref, &index_key); + if (key_ref) goto found_matching_key; } @@ -856,23 +864,24 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; perm |= KEY_USR_VIEW; - if (ktype->read) + if (index_key.type->read) perm |= KEY_POS_READ; - if (ktype == &key_type_keyring || ktype->update) + if (index_key.type == &key_type_keyring || + index_key.type->update) perm |= KEY_POS_WRITE; } /* allocate a new key */ - key = key_alloc(ktype, description, cred->fsuid, cred->fsgid, cred, - perm, flags); + key = key_alloc(index_key.type, index_key.description, + cred->fsuid, cred->fsgid, cred, perm, flags); if (IS_ERR(key)) { key_ref = ERR_CAST(key); goto error_link_end; } /* instantiate it and link it into the target keyring */ - ret = __key_instantiate_and_link(key, &prep, keyring, NULL, &prealloc); + ret = __key_instantiate_and_link(key, &prep, keyring, NULL, &edit); if (ret < 0) { key_put(key); key_ref = ERR_PTR(ret); @@ -882,12 +891,12 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, key_ref = make_key_ref(key, is_key_possessed(keyring_ref)); error_link_end: - __key_link_end(keyring, ktype, prealloc); + __key_link_end(keyring, &index_key, edit); error_free_prep: - if (ktype->preparse) - ktype->free_preparse(&prep); + if (index_key.type->preparse) + index_key.type->free_preparse(&prep); error_put_type: - key_type_put(ktype); + key_type_put(index_key.type); error: return key_ref; @@ -895,7 +904,7 @@ error: /* we found a matching key, so we're going to try to update it * - we can drop the locks first as we have the key pinned */ - __key_link_end(keyring, ktype, prealloc); + __key_link_end(keyring, &index_key, edit); key_ref = __key_update(key_ref, &prep); goto error_free_prep; diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 33cfd27..cee72ce 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -1667,6 +1667,9 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, case KEYCTL_INVALIDATE: return keyctl_invalidate_key((key_serial_t) arg2); + case KEYCTL_GET_PERSISTENT: + return keyctl_get_persistent((uid_t)arg2, (key_serial_t)arg3); + default: return -EOPNOTSUPP; } diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 6ece7f2..9b6f6e0 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -1,6 +1,6 @@ /* Keyring handling * - * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved. + * Copyright (C) 2004-2005, 2008, 2013 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or @@ -17,25 +17,11 @@ #include <linux/seq_file.h> #include <linux/err.h> #include <keys/keyring-type.h> +#include <keys/user-type.h> +#include <linux/assoc_array_priv.h> #include <linux/uaccess.h> #include "internal.h" -#define rcu_dereference_locked_keyring(keyring) \ - (rcu_dereference_protected( \ - (keyring)->payload.subscriptions, \ - rwsem_is_locked((struct rw_semaphore *)&(keyring)->sem))) - -#define rcu_deref_link_locked(klist, index, keyring) \ - (rcu_dereference_protected( \ - (klist)->keys[index], \ - rwsem_is_locked((struct rw_semaphore *)&(keyring)->sem))) - -#define MAX_KEYRING_LINKS \ - min_t(size_t, USHRT_MAX - 1, \ - ((PAGE_SIZE - sizeof(struct keyring_list)) / sizeof(struct key *))) - -#define KEY_LINK_FIXQUOTA 1UL - /* * When plumbing the depths of the key tree, this sets a hard limit * set on how deep we're willing to go. @@ -47,6 +33,28 @@ */ #define KEYRING_NAME_HASH_SIZE (1 << 5) +/* + * We mark pointers we pass to the associative array with bit 1 set if + * they're keyrings and clear otherwise. + */ +#define KEYRING_PTR_SUBTYPE 0x2UL + +static inline bool keyring_ptr_is_keyring(const struct assoc_array_ptr *x) +{ + return (unsigned long)x & KEYRING_PTR_SUBTYPE; +} +static inline struct key *keyring_ptr_to_key(const struct assoc_array_ptr *x) +{ + void *object = assoc_array_ptr_to_leaf(x); + return (struct key *)((unsigned long)object & ~KEYRING_PTR_SUBTYPE); +} +static inline void *keyring_key_to_ptr(struct key *key) +{ + if (key->type == &key_type_keyring) + return (void *)((unsigned long)key | KEYRING_PTR_SUBTYPE); + return key; +} + static struct list_head keyring_name_hash[KEYRING_NAME_HASH_SIZE]; static DEFINE_RWLOCK(keyring_name_lock); @@ -67,7 +75,6 @@ static inline unsigned keyring_hash(const char *desc) */ static int keyring_instantiate(struct key *keyring, struct key_preparsed_payload *prep); -static int keyring_match(const struct key *keyring, const void *criterion); static void keyring_revoke(struct key *keyring); static void keyring_destroy(struct key *keyring); static void keyring_describe(const struct key *keyring, struct seq_file *m); @@ -76,9 +83,9 @@ static long keyring_read(const struct key *keyring, struct key_type key_type_keyring = { .name = "keyring", - .def_datalen = sizeof(struct keyring_list), + .def_datalen = 0, .instantiate = keyring_instantiate, - .match = keyring_match, + .match = user_match, .revoke = keyring_revoke, .destroy = keyring_destroy, .describe = keyring_describe, @@ -127,6 +134,7 @@ static int keyring_instantiate(struct key *keyring, ret = -EINVAL; if (prep->datalen == 0) { + assoc_array_init(&keyring->keys); /* make the keyring available by name if it has one */ keyring_publish_name(keyring); ret = 0; @@ -136,15 +144,226 @@ static int keyring_instantiate(struct key *keyring, } /* - * Match keyrings on their name + * Multiply 64-bits by 32-bits to 96-bits and fold back to 64-bit. Ideally we'd + * fold the carry back too, but that requires inline asm. + */ +static u64 mult_64x32_and_fold(u64 x, u32 y) +{ + u64 hi = (u64)(u32)(x >> 32) * y; + u64 lo = (u64)(u32)(x) * y; + return lo + ((u64)(u32)hi << 32) + (u32)(hi >> 32); +} + +/* + * Hash a key type and description. */ -static int keyring_match(const struct key *keyring, const void *description) +static unsigned long hash_key_type_and_desc(const struct keyring_index_key *index_key) { - return keyring->description && - strcmp(keyring->description, description) == 0; + const unsigned level_shift = ASSOC_ARRAY_LEVEL_STEP; + const unsigned long level_mask = ASSOC_ARRAY_LEVEL_STEP_MASK; + const char *description = index_key->description; + unsigned long hash, type; + u32 piece; + u64 acc; + int n, desc_len = index_key->desc_len; + + type = (unsigned long)index_key->type; + + acc = mult_64x32_and_fold(type, desc_len + 13); + acc = mult_64x32_and_fold(acc, 9207); + for (;;) { + n = desc_len; + if (n <= 0) + break; + if (n > 4) + n = 4; + piece = 0; + memcpy(&piece, description, n); + description += n; + desc_len -= n; + acc = mult_64x32_and_fold(acc, piece); + acc = mult_64x32_and_fold(acc, 9207); + } + + /* Fold the hash down to 32 bits if need be. */ + hash = acc; + if (ASSOC_ARRAY_KEY_CHUNK_SIZE == 32) + hash ^= acc >> 32; + + /* Squidge all the keyrings into a separate part of the tree to + * ordinary keys by making sure the lowest level segment in the hash is + * zero for keyrings and non-zero otherwise. + */ + if (index_key->type != &key_type_keyring && (hash & level_mask) == 0) + return hash | (hash >> (ASSOC_ARRAY_KEY_CHUNK_SIZE - level_shift)) | 1; + if (index_key->type == &key_type_keyring && (hash & level_mask) != 0) + return (hash + (hash << level_shift)) & ~level_mask; + return hash; } /* + * Build the next index key chunk. + * + * On 32-bit systems the index key is laid out as: + * + * 0 4 5 9... + * hash desclen typeptr desc[] + * + * On 64-bit systems: + * + * 0 8 9 17... + * hash desclen typeptr desc[] + * + * We return it one word-sized chunk at a time. + */ +static unsigned long keyring_get_key_chunk(const void *data, int level) +{ + const struct keyring_index_key *index_key = data; + unsigned long chunk = 0; + long offset = 0; + int desc_len = index_key->desc_len, n = sizeof(chunk); + + level /= ASSOC_ARRAY_KEY_CHUNK_SIZE; + switch (level) { + case 0: + return hash_key_type_and_desc(index_key); + case 1: + return ((unsigned long)index_key->type << 8) | desc_len; + case 2: + if (desc_len == 0) + return (u8)((unsigned long)index_key->type >> + (ASSOC_ARRAY_KEY_CHUNK_SIZE - 8)); + n--; + offset = 1; + default: + offset += sizeof(chunk) - 1; + offset += (level - 3) * sizeof(chunk); + if (offset >= desc_len) + return 0; + desc_len -= offset; + if (desc_len > n) + desc_len = n; + offset += desc_len; + do { + chunk <<= 8; + chunk |= ((u8*)index_key->description)[--offset]; + } while (--desc_len > 0); + + if (level == 2) { + chunk <<= 8; + chunk |= (u8)((unsigned long)index_key->type >> + (ASSOC_ARRAY_KEY_CHUNK_SIZE - 8)); + } + return chunk; + } +} + +static unsigned long keyring_get_object_key_chunk(const void *object, int level) +{ + const struct key *key = keyring_ptr_to_key(object); + return keyring_get_key_chunk(&key->index_key, level); +} + +static bool keyring_compare_object(const void *object, const void *data) +{ + const struct keyring_index_key *index_key = data; + const struct key *key = keyring_ptr_to_key(object); + + return key->index_key.type == index_key->type && + key->index_key.desc_len == index_key->desc_len && + memcmp(key->index_key.description, index_key->description, + index_key->desc_len) == 0; +} + +/* + * Compare the index keys of a pair of objects and determine the bit position + * at which they differ - if they differ. + */ +static int keyring_diff_objects(const void *_a, const void *_b) +{ + const struct key *key_a = keyring_ptr_to_key(_a); + const struct key *key_b = keyring_ptr_to_key(_b); + const struct keyring_index_key *a = &key_a->index_key; + const struct keyring_index_key *b = &key_b->index_key; + unsigned long seg_a, seg_b; + int level, i; + + level = 0; + seg_a = hash_key_type_and_desc(a); + seg_b = hash_key_type_and_desc(b); + if ((seg_a ^ seg_b) != 0) + goto differ; + + /* The number of bits contributed by the hash is controlled by a + * constant in the assoc_array headers. Everything else thereafter we + * can deal with as being machine word-size dependent. + */ + level += ASSOC_ARRAY_KEY_CHUNK_SIZE / 8; + seg_a = a->desc_len; + seg_b = b->desc_len; + if ((seg_a ^ seg_b) != 0) + goto differ; + + /* The next bit may not work on big endian */ + level++; + seg_a = (unsigned long)a->type; + seg_b = (unsigned long)b->type; + if ((seg_a ^ seg_b) != 0) + goto differ; + + level += sizeof(unsigned long); + if (a->desc_len == 0) + goto same; + + i = 0; + if (((unsigned long)a->description | (unsigned long)b->description) & + (sizeof(unsigned long) - 1)) { + do { + seg_a = *(unsigned long *)(a->description + i); + seg_b = *(unsigned long *)(b->description + i); + if ((seg_a ^ seg_b) != 0) + goto differ_plus_i; + i += sizeof(unsigned long); + } while (i < (a->desc_len & (sizeof(unsigned long) - 1))); + } + + for (; i < a->desc_len; i++) { + seg_a = *(unsigned char *)(a->description + i); + seg_b = *(unsigned char *)(b->description + i); + if ((seg_a ^ seg_b) != 0) + goto differ_plus_i; + } + +same: + return -1; + +differ_plus_i: + level += i; +differ: + i = level * 8 + __ffs(seg_a ^ seg_b); + return i; +} + +/* + * Free an object after stripping the keyring flag off of the pointer. + */ +static void keyring_free_object(void *object) +{ + key_put(keyring_ptr_to_key(object)); +} + +/* + * Operations for keyring management by the index-tree routines. + */ +static const struct assoc_array_ops keyring_assoc_array_ops = { + .get_key_chunk = keyring_get_key_chunk, + .get_object_key_chunk = keyring_get_object_key_chunk, + .compare_object = keyring_compare_object, + .diff_objects = keyring_diff_objects, + .free_object = keyring_free_object, +}; + +/* * Clean up a keyring when it is destroyed. Unpublish its name if it had one * and dispose of its data. * @@ -155,9 +374,6 @@ static int keyring_match(const struct key *keyring, const void *description) */ static void keyring_destroy(struct key *keyring) { - struct keyring_list *klist; - int loop; - if (keyring->description) { write_lock(&keyring_name_lock); @@ -168,12 +384,7 @@ static void keyring_destroy(struct key *keyring) write_unlock(&keyring_name_lock); } - klist = rcu_access_pointer(keyring->payload.subscriptions); - if (klist) { - for (loop = klist->nkeys - 1; loop >= 0; loop--) - key_put(rcu_access_pointer(klist->keys[loop])); - kfree(klist); - } + assoc_array_destroy(&keyring->keys, &keyring_assoc_array_ops); } /* @@ -181,76 +392,88 @@ static void keyring_destroy(struct key *keyring) */ static void keyring_describe(const struct key *keyring, struct seq_file *m) { - struct keyring_list *klist; - if (keyring->description) seq_puts(m, keyring->description); else seq_puts(m, "[anon]"); if (key_is_instantiated(keyring)) { - rcu_read_lock(); - klist = rcu_dereference(keyring->payload.subscriptions); - if (klist) - seq_printf(m, ": %u/%u", klist->nkeys, klist->maxkeys); + if (keyring->keys.nr_leaves_on_tree != 0) + seq_printf(m, ": %lu", keyring->keys.nr_leaves_on_tree); else seq_puts(m, ": empty"); - rcu_read_unlock(); } } +struct keyring_read_iterator_context { + size_t qty; + size_t count; + key_serial_t __user *buffer; +}; + +static int keyring_read_iterator(const void *object, void *data) +{ + struct keyring_read_iterator_context *ctx = data; + const struct key *key = keyring_ptr_to_key(object); + int ret; + + kenter("{%s,%d},,{%zu/%zu}", + key->type->name, key->serial, ctx->count, ctx->qty); + + if (ctx->count >= ctx->qty) + return 1; + + ret = put_user(key->serial, ctx->buffer); + if (ret < 0) + return ret; + ctx->buffer++; + ctx->count += sizeof(key->serial); + return 0; +} + /* * Read a list of key IDs from the keyring's contents in binary form * - * The keyring's semaphore is read-locked by the caller. + * The keyring's semaphore is read-locked by the caller. This prevents someone + * from modifying it under us - which could cause us to read key IDs multiple + * times. */ static long keyring_read(const struct key *keyring, char __user *buffer, size_t buflen) { - struct keyring_list *klist; - struct key *key; - size_t qty, tmp; - int loop, ret; + struct keyring_read_iterator_context ctx; + unsigned long nr_keys; + int ret; - ret = 0; - klist = rcu_dereference_locked_keyring(keyring); - if (klist) { - /* calculate how much data we could return */ - qty = klist->nkeys * sizeof(key_serial_t); - - if (buffer && buflen > 0) { - if (buflen > qty) - buflen = qty; - - /* copy the IDs of the subscribed keys into the - * buffer */ - ret = -EFAULT; - - for (loop = 0; loop < klist->nkeys; loop++) { - key = rcu_deref_link_locked(klist, loop, - keyring); - - tmp = sizeof(key_serial_t); - if (tmp > buflen) - tmp = buflen; - - if (copy_to_user(buffer, - &key->serial, - tmp) != 0) - goto error; - - buflen -= tmp; - if (buflen == 0) - break; - buffer += tmp; - } - } + kenter("{%d},,%zu", key_serial(keyring), buflen); - ret = qty; + if (buflen & (sizeof(key_serial_t) - 1)) + return -EINVAL; + + nr_keys = keyring->keys.nr_leaves_on_tree; + if (nr_keys == 0) + return 0; + + /* Calculate how much data we could return */ + ctx.qty = nr_keys * sizeof(key_serial_t); + + if (!buffer || !buflen) + return ctx.qty; + + if (buflen > ctx.qty) + ctx.qty = buflen; + + /* Copy the IDs of the subscribed keys into the buffer */ + ctx.buffer = (key_serial_t __user *)buffer; + ctx.count = 0; + ret = assoc_array_iterate(&keyring->keys, keyring_read_iterator, &ctx); + if (ret < 0) { + kleave(" = %d [iterate]", ret); + return ret; } -error: - return ret; + kleave(" = %zu [ok]", ctx.count); + return ctx.count; } /* @@ -277,227 +500,360 @@ struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid, } EXPORT_SYMBOL(keyring_alloc); -/** - * keyring_search_aux - Search a keyring tree for a key matching some criteria - * @keyring_ref: A pointer to the keyring with possession indicator. - * @cred: The credentials to use for permissions checks. - * @type: The type of key to search for. - * @description: Parameter for @match. - * @match: Function to rule on whether or not a key is the one required. - * @no_state_check: Don't check if a matching key is bad - * - * Search the supplied keyring tree for a key that matches the criteria given. - * The root keyring and any linked keyrings must grant Search permission to the - * caller to be searchable and keys can only be found if they too grant Search - * to the caller. The possession flag on the root keyring pointer controls use - * of the possessor bits in permissions checking of the entire tree. In - * addition, the LSM gets to forbid keyring searches and key matches. - * - * The search is performed as a breadth-then-depth search up to the prescribed - * limit (KEYRING_SEARCH_MAX_DEPTH). - * - * Keys are matched to the type provided and are then filtered by the match - * function, which is given the description to use in any way it sees fit. The - * match function may use any attributes of a key that it wishes to to - * determine the match. Normally the match function from the key type would be - * used. - * - * RCU is used to prevent the keyring key lists from disappearing without the - * need to take lots of locks. - * - * Returns a pointer to the found key and increments the key usage count if - * successful; -EAGAIN if no matching keys were found, or if expired or revoked - * keys were found; -ENOKEY if only negative keys were found; -ENOTDIR if the - * specified keyring wasn't a keyring. - * - * In the case of a successful return, the possession attribute from - * @keyring_ref is propagated to the returned key reference. +/* + * Iteration function to consider each key found. */ -key_ref_t keyring_search_aux(key_ref_t keyring_ref, - const struct cred *cred, - struct key_type *type, - const void *description, - key_match_func_t match, - bool no_state_check) +static int keyring_search_iterator(const void *object, void *iterator_data) { - struct { - /* Need a separate keylist pointer for RCU purposes */ - struct key *keyring; - struct keyring_list *keylist; - int kix; - } stack[KEYRING_SEARCH_MAX_DEPTH]; + struct keyring_search_context *ctx = iterator_data; + const struct key *key = keyring_ptr_to_key(object); + unsigned long kflags = key->flags; - struct keyring_list *keylist; - struct timespec now; - unsigned long possessed, kflags; - struct key *keyring, *key; - key_ref_t key_ref; - long err; - int sp, nkeys, kix; - - keyring = key_ref_to_ptr(keyring_ref); - possessed = is_key_possessed(keyring_ref); - key_check(keyring); + kenter("{%d}", key->serial); - /* top keyring must have search permission to begin the search */ - err = key_task_permission(keyring_ref, cred, KEY_SEARCH); - if (err < 0) { - key_ref = ERR_PTR(err); - goto error; + /* ignore keys not of this type */ + if (key->type != ctx->index_key.type) { + kleave(" = 0 [!type]"); + return 0; } - key_ref = ERR_PTR(-ENOTDIR); - if (keyring->type != &key_type_keyring) - goto error; + /* skip invalidated, revoked and expired keys */ + if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) { + if (kflags & ((1 << KEY_FLAG_INVALIDATED) | + (1 << KEY_FLAG_REVOKED))) { + ctx->result = ERR_PTR(-EKEYREVOKED); + kleave(" = %d [invrev]", ctx->skipped_ret); + goto skipped; + } - rcu_read_lock(); + if (key->expiry && ctx->now.tv_sec >= key->expiry) { + ctx->result = ERR_PTR(-EKEYEXPIRED); + kleave(" = %d [expire]", ctx->skipped_ret); + goto skipped; + } + } - now = current_kernel_time(); - err = -EAGAIN; - sp = 0; - - /* firstly we should check to see if this top-level keyring is what we - * are looking for */ - key_ref = ERR_PTR(-EAGAIN); - kflags = keyring->flags; - if (keyring->type == type && match(keyring, description)) { - key = keyring; - if (no_state_check) - goto found; + /* keys that don't match */ + if (!ctx->match(key, ctx->match_data)) { + kleave(" = 0 [!match]"); + return 0; + } - /* check it isn't negative and hasn't expired or been - * revoked */ - if (kflags & (1 << KEY_FLAG_REVOKED)) - goto error_2; - if (key->expiry && now.tv_sec >= key->expiry) - goto error_2; - key_ref = ERR_PTR(key->type_data.reject_error); - if (kflags & (1 << KEY_FLAG_NEGATIVE)) - goto error_2; - goto found; + /* key must have search permissions */ + if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM) && + key_task_permission(make_key_ref(key, ctx->possessed), + ctx->cred, KEY_SEARCH) < 0) { + ctx->result = ERR_PTR(-EACCES); + kleave(" = %d [!perm]", ctx->skipped_ret); + goto skipped; } - /* otherwise, the top keyring must not be revoked, expired, or - * negatively instantiated if we are to search it */ - key_ref = ERR_PTR(-EAGAIN); - if (kflags & ((1 << KEY_FLAG_INVALIDATED) | - (1 << KEY_FLAG_REVOKED) | - (1 << KEY_FLAG_NEGATIVE)) || - (keyring->expiry && now.tv_sec >= keyring->expiry)) - goto error_2; - - /* start processing a new keyring */ -descend: - kflags = keyring->flags; - if (kflags & ((1 << KEY_FLAG_INVALIDATED) | - (1 << KEY_FLAG_REVOKED))) - goto not_this_keyring; + if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) { + /* we set a different error code if we pass a negative key */ + if (kflags & (1 << KEY_FLAG_NEGATIVE)) { + ctx->result = ERR_PTR(key->type_data.reject_error); + kleave(" = %d [neg]", ctx->skipped_ret); + goto skipped; + } + } - keylist = rcu_dereference(keyring->payload.subscriptions); - if (!keylist) - goto not_this_keyring; + /* Found */ + ctx->result = make_key_ref(key, ctx->possessed); + kleave(" = 1 [found]"); + return 1; - /* iterate through the keys in this keyring first */ - nkeys = keylist->nkeys; - smp_rmb(); - for (kix = 0; kix < nkeys; kix++) { - key = rcu_dereference(keylist->keys[kix]); - kflags = key->flags; +skipped: + return ctx->skipped_ret; +} - /* ignore keys not of this type */ - if (key->type != type) - continue; +/* + * Search inside a keyring for a key. We can search by walking to it + * directly based on its index-key or we can iterate over the entire + * tree looking for it, based on the match function. + */ +static int search_keyring(struct key *keyring, struct keyring_search_context *ctx) +{ + if ((ctx->flags & KEYRING_SEARCH_LOOKUP_TYPE) == + KEYRING_SEARCH_LOOKUP_DIRECT) { + const void *object; + + object = assoc_array_find(&keyring->keys, + &keyring_assoc_array_ops, + &ctx->index_key); + return object ? ctx->iterator(object, ctx) : 0; + } + return assoc_array_iterate(&keyring->keys, ctx->iterator, ctx); +} - /* skip invalidated, revoked and expired keys */ - if (!no_state_check) { - if (kflags & ((1 << KEY_FLAG_INVALIDATED) | - (1 << KEY_FLAG_REVOKED))) - continue; +/* + * Search a tree of keyrings that point to other keyrings up to the maximum + * depth. + */ +static bool search_nested_keyrings(struct key *keyring, + struct keyring_search_context *ctx) +{ + struct { + struct key *keyring; + struct assoc_array_node *node; + int slot; + } stack[KEYRING_SEARCH_MAX_DEPTH]; - if (key->expiry && now.tv_sec >= key->expiry) - continue; - } + struct assoc_array_shortcut *shortcut; + struct assoc_array_node *node; + struct assoc_array_ptr *ptr; + struct key *key; + int sp = 0, slot; - /* keys that don't match */ - if (!match(key, description)) - continue; + kenter("{%d},{%s,%s}", + keyring->serial, + ctx->index_key.type->name, + ctx->index_key.description); - /* key must have search permissions */ - if (key_task_permission(make_key_ref(key, possessed), - cred, KEY_SEARCH) < 0) - continue; + if (ctx->index_key.description) + ctx->index_key.desc_len = strlen(ctx->index_key.description); - if (no_state_check) + /* Check to see if this top-level keyring is what we are looking for + * and whether it is valid or not. + */ + if (ctx->flags & KEYRING_SEARCH_LOOKUP_ITERATE || + keyring_compare_object(keyring, &ctx->index_key)) { + ctx->skipped_ret = 2; + ctx->flags |= KEYRING_SEARCH_DO_STATE_CHECK; + switch (ctx->iterator(keyring_key_to_ptr(keyring), ctx)) { + case 1: goto found; - - /* we set a different error code if we pass a negative key */ - if (kflags & (1 << KEY_FLAG_NEGATIVE)) { - err = key->type_data.reject_error; - continue; + case 2: + return false; + default: + break; } + } + ctx->skipped_ret = 0; + if (ctx->flags & KEYRING_SEARCH_NO_STATE_CHECK) + ctx->flags &= ~KEYRING_SEARCH_DO_STATE_CHECK; + + /* Start processing a new keyring */ +descend_to_keyring: + kdebug("descend to %d", keyring->serial); + if (keyring->flags & ((1 << KEY_FLAG_INVALIDATED) | + (1 << KEY_FLAG_REVOKED))) + goto not_this_keyring; + + /* Search through the keys in this keyring before its searching its + * subtrees. + */ + if (search_keyring(keyring, ctx)) goto found; - } - /* search through the keyrings nested in this one */ - kix = 0; -ascend: - nkeys = keylist->nkeys; - smp_rmb(); - for (; kix < nkeys; kix++) { - key = rcu_dereference(keylist->keys[kix]); - if (key->type != &key_type_keyring) - continue; + /* Then manually iterate through the keyrings nested in this one. + * + * Start from the root node of the index tree. Because of the way the + * hash function has been set up, keyrings cluster on the leftmost + * branch of the root node (root slot 0) or in the root node itself. + * Non-keyrings avoid the leftmost branch of the root entirely (root + * slots 1-15). + */ + ptr = ACCESS_ONCE(keyring->keys.root); + if (!ptr) + goto not_this_keyring; - /* recursively search nested keyrings - * - only search keyrings for which we have search permission + if (assoc_array_ptr_is_shortcut(ptr)) { + /* If the root is a shortcut, either the keyring only contains + * keyring pointers (everything clusters behind root slot 0) or + * doesn't contain any keyring pointers. */ - if (sp >= KEYRING_SEARCH_MAX_DEPTH) + shortcut = assoc_array_ptr_to_shortcut(ptr); + smp_read_barrier_depends(); + if ((shortcut->index_key[0] & ASSOC_ARRAY_FAN_MASK) != 0) + goto not_this_keyring; + + ptr = ACCESS_ONCE(shortcut->next_node); + node = assoc_array_ptr_to_node(ptr); + goto begin_node; + } + + node = assoc_array_ptr_to_node(ptr); + smp_read_barrier_depends(); + + ptr = node->slots[0]; + if (!assoc_array_ptr_is_meta(ptr)) + goto begin_node; + +descend_to_node: + /* Descend to a more distal node in this keyring's content tree and go + * through that. + */ + kdebug("descend"); + if (assoc_array_ptr_is_shortcut(ptr)) { + shortcut = assoc_array_ptr_to_shortcut(ptr); + smp_read_barrier_depends(); + ptr = ACCESS_ONCE(shortcut->next_node); + BUG_ON(!assoc_array_ptr_is_node(ptr)); + node = assoc_array_ptr_to_node(ptr); + } + +begin_node: + kdebug("begin_node"); + smp_read_barrier_depends(); + slot = 0; +ascend_to_node: + /* Go through the slots in a node */ + for (; slot < ASSOC_ARRAY_FAN_OUT; slot++) { + ptr = ACCESS_ONCE(node->slots[slot]); + + if (assoc_array_ptr_is_meta(ptr) && node->back_pointer) + goto descend_to_node; + + if (!keyring_ptr_is_keyring(ptr)) continue; - if (key_task_permission(make_key_ref(key, possessed), - cred, KEY_SEARCH) < 0) + key = keyring_ptr_to_key(ptr); + + if (sp >= KEYRING_SEARCH_MAX_DEPTH) { + if (ctx->flags & KEYRING_SEARCH_DETECT_TOO_DEEP) { + ctx->result = ERR_PTR(-ELOOP); + return false; + } + goto not_this_keyring; + } + + /* Search a nested keyring */ + if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM) && + key_task_permission(make_key_ref(key, ctx->possessed), + ctx->cred, KEY_SEARCH) < 0) continue; /* stack the current position */ stack[sp].keyring = keyring; - stack[sp].keylist = keylist; - stack[sp].kix = kix; + stack[sp].node = node; + stack[sp].slot = slot; sp++; /* begin again with the new keyring */ keyring = key; - goto descend; + goto descend_to_keyring; + } + + /* We've dealt with all the slots in the current node, so now we need + * to ascend to the parent and continue processing there. + */ + ptr = ACCESS_ONCE(node->back_pointer); + slot = node->parent_slot; + + if (ptr && assoc_array_ptr_is_shortcut(ptr)) { + shortcut = assoc_array_ptr_to_shortcut(ptr); + smp_read_barrier_depends(); + ptr = ACCESS_ONCE(shortcut->back_pointer); + slot = shortcut->parent_slot; + } + if (!ptr) + goto not_this_keyring; + node = assoc_array_ptr_to_node(ptr); + smp_read_barrier_depends(); + slot++; + + /* If we've ascended to the root (zero backpointer), we must have just + * finished processing the leftmost branch rather than the root slots - + * so there can't be any more keyrings for us to find. + */ + if (node->back_pointer) { + kdebug("ascend %d", slot); + goto ascend_to_node; } - /* the keyring we're looking at was disqualified or didn't contain a - * matching key */ + /* The keyring we're looking at was disqualified or didn't contain a + * matching key. + */ not_this_keyring: - if (sp > 0) { - /* resume the processing of a keyring higher up in the tree */ - sp--; - keyring = stack[sp].keyring; - keylist = stack[sp].keylist; - kix = stack[sp].kix + 1; - goto ascend; + kdebug("not_this_keyring %d", sp); + if (sp <= 0) { + kleave(" = false"); + return false; } - key_ref = ERR_PTR(err); - goto error_2; + /* Resume the processing of a keyring higher up in the tree */ + sp--; + keyring = stack[sp].keyring; + node = stack[sp].node; + slot = stack[sp].slot + 1; + kdebug("ascend to %d [%d]", keyring->serial, slot); + goto ascend_to_node; - /* we found a viable match */ + /* We found a viable match */ found: - atomic_inc(&key->usage); - key->last_used_at = now.tv_sec; - keyring->last_used_at = now.tv_sec; - while (sp > 0) - stack[--sp].keyring->last_used_at = now.tv_sec; + key = key_ref_to_ptr(ctx->result); key_check(key); - key_ref = make_key_ref(key, possessed); -error_2: + if (!(ctx->flags & KEYRING_SEARCH_NO_UPDATE_TIME)) { + key->last_used_at = ctx->now.tv_sec; + keyring->last_used_at = ctx->now.tv_sec; + while (sp > 0) + stack[--sp].keyring->last_used_at = ctx->now.tv_sec; + } + kleave(" = true"); + return true; +} + +/** + * keyring_search_aux - Search a keyring tree for a key matching some criteria + * @keyring_ref: A pointer to the keyring with possession indicator. + * @ctx: The keyring search context. + * + * Search the supplied keyring tree for a key that matches the criteria given. + * The root keyring and any linked keyrings must grant Search permission to the + * caller to be searchable and keys can only be found if they too grant Search + * to the caller. The possession flag on the root keyring pointer controls use + * of the possessor bits in permissions checking of the entire tree. In + * addition, the LSM gets to forbid keyring searches and key matches. + * + * The search is performed as a breadth-then-depth search up to the prescribed + * limit (KEYRING_SEARCH_MAX_DEPTH). + * + * Keys are matched to the type provided and are then filtered by the match + * function, which is given the description to use in any way it sees fit. The + * match function may use any attributes of a key that it wishes to to + * determine the match. Normally the match function from the key type would be + * used. + * + * RCU can be used to prevent the keyring key lists from disappearing without + * the need to take lots of locks. + * + * Returns a pointer to the found key and increments the key usage count if + * successful; -EAGAIN if no matching keys were found, or if expired or revoked + * keys were found; -ENOKEY if only negative keys were found; -ENOTDIR if the + * specified keyring wasn't a keyring. + * + * In the case of a successful return, the possession attribute from + * @keyring_ref is propagated to the returned key reference. + */ +key_ref_t keyring_search_aux(key_ref_t keyring_ref, + struct keyring_search_context *ctx) +{ + struct key *keyring; + long err; + + ctx->iterator = keyring_search_iterator; + ctx->possessed = is_key_possessed(keyring_ref); + ctx->result = ERR_PTR(-EAGAIN); + + keyring = key_ref_to_ptr(keyring_ref); + key_check(keyring); + + if (keyring->type != &key_type_keyring) + return ERR_PTR(-ENOTDIR); + + if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM)) { + err = key_task_permission(keyring_ref, ctx->cred, KEY_SEARCH); + if (err < 0) + return ERR_PTR(err); + } + + rcu_read_lock(); + ctx->now = current_kernel_time(); + if (search_nested_keyrings(keyring, ctx)) + __key_get(key_ref_to_ptr(ctx->result)); rcu_read_unlock(); -error: - return key_ref; + return ctx->result; } /** @@ -507,77 +863,73 @@ error: * @description: The name of the keyring we want to find. * * As keyring_search_aux() above, but using the current task's credentials and - * type's default matching function. + * type's default matching function and preferred search method. */ key_ref_t keyring_search(key_ref_t keyring, struct key_type *type, const char *description) { - if (!type->match) + struct keyring_search_context ctx = { + .index_key.type = type, + .index_key.description = description, + .cred = current_cred(), + .match = type->match, + .match_data = description, + .flags = (type->def_lookup_type | + KEYRING_SEARCH_DO_STATE_CHECK), + }; + + if (!ctx.match) return ERR_PTR(-ENOKEY); - return keyring_search_aux(keyring, current->cred, - type, description, type->match, false); + return keyring_search_aux(keyring, &ctx); } EXPORT_SYMBOL(keyring_search); /* - * Search the given keyring only (no recursion). + * Search the given keyring for a key that might be updated. * * The caller must guarantee that the keyring is a keyring and that the - * permission is granted to search the keyring as no check is made here. - * - * RCU is used to make it unnecessary to lock the keyring key list here. + * permission is granted to modify the keyring as no check is made here. The + * caller must also hold a lock on the keyring semaphore. * * Returns a pointer to the found key with usage count incremented if - * successful and returns -ENOKEY if not found. Revoked keys and keys not - * providing the requested permission are skipped over. + * successful and returns NULL if not found. Revoked and invalidated keys are + * skipped over. * * If successful, the possession indicator is propagated from the keyring ref * to the returned key reference. */ -key_ref_t __keyring_search_one(key_ref_t keyring_ref, - const struct key_type *ktype, - const char *description, - key_perm_t perm) +key_ref_t find_key_to_update(key_ref_t keyring_ref, + const struct keyring_index_key *index_key) { - struct keyring_list *klist; - unsigned long possessed; struct key *keyring, *key; - int nkeys, loop; + const void *object; keyring = key_ref_to_ptr(keyring_ref); - possessed = is_key_possessed(keyring_ref); - rcu_read_lock(); + kenter("{%d},{%s,%s}", + keyring->serial, index_key->type->name, index_key->description); - klist = rcu_dereference(keyring->payload.subscriptions); - if (klist) { - nkeys = klist->nkeys; - smp_rmb(); - for (loop = 0; loop < nkeys ; loop++) { - key = rcu_dereference(klist->keys[loop]); - if (key->type == ktype && - (!key->type->match || - key->type->match(key, description)) && - key_permission(make_key_ref(key, possessed), - perm) == 0 && - !(key->flags & ((1 << KEY_FLAG_INVALIDATED) | - (1 << KEY_FLAG_REVOKED))) - ) - goto found; - } - } + object = assoc_array_find(&keyring->keys, &keyring_assoc_array_ops, + index_key); - rcu_read_unlock(); - return ERR_PTR(-ENOKEY); + if (object) + goto found; + + kleave(" = NULL"); + return NULL; found: - atomic_inc(&key->usage); - keyring->last_used_at = key->last_used_at = - current_kernel_time().tv_sec; - rcu_read_unlock(); - return make_key_ref(key, possessed); + key = keyring_ptr_to_key(object); + if (key->flags & ((1 << KEY_FLAG_INVALIDATED) | + (1 << KEY_FLAG_REVOKED))) { + kleave(" = NULL [x]"); + return NULL; + } + __key_get(key); + kleave(" = {%d}", key->serial); + return make_key_ref(key, is_key_possessed(keyring_ref)); } /* @@ -640,6 +992,19 @@ out: return keyring; } +static int keyring_detect_cycle_iterator(const void *object, + void *iterator_data) +{ + struct keyring_search_context *ctx = iterator_data; + const struct key *key = keyring_ptr_to_key(object); + + kenter("{%d}", key->serial); + + BUG_ON(key != ctx->match_data); + ctx->result = ERR_PTR(-EDEADLK); + return 1; +} + /* * See if a cycle will will be created by inserting acyclic tree B in acyclic * tree A at the topmost level (ie: as a direct child of A). @@ -649,116 +1014,39 @@ out: */ static int keyring_detect_cycle(struct key *A, struct key *B) { - struct { - struct keyring_list *keylist; - int kix; - } stack[KEYRING_SEARCH_MAX_DEPTH]; - - struct keyring_list *keylist; - struct key *subtree, *key; - int sp, nkeys, kix, ret; + struct keyring_search_context ctx = { + .index_key = A->index_key, + .match_data = A, + .iterator = keyring_detect_cycle_iterator, + .flags = (KEYRING_SEARCH_LOOKUP_DIRECT | + KEYRING_SEARCH_NO_STATE_CHECK | + KEYRING_SEARCH_NO_UPDATE_TIME | + KEYRING_SEARCH_NO_CHECK_PERM | + KEYRING_SEARCH_DETECT_TOO_DEEP), + }; rcu_read_lock(); - - ret = -EDEADLK; - if (A == B) - goto cycle_detected; - - subtree = B; - sp = 0; - - /* start processing a new keyring */ -descend: - if (test_bit(KEY_FLAG_REVOKED, &subtree->flags)) - goto not_this_keyring; - - keylist = rcu_dereference(subtree->payload.subscriptions); - if (!keylist) - goto not_this_keyring; - kix = 0; - -ascend: - /* iterate through the remaining keys in this keyring */ - nkeys = keylist->nkeys; - smp_rmb(); - for (; kix < nkeys; kix++) { - key = rcu_dereference(keylist->keys[kix]); - - if (key == A) - goto cycle_detected; - - /* recursively check nested keyrings */ - if (key->type == &key_type_keyring) { - if (sp >= KEYRING_SEARCH_MAX_DEPTH) - goto too_deep; - - /* stack the current position */ - stack[sp].keylist = keylist; - stack[sp].kix = kix; - sp++; - - /* begin again with the new keyring */ - subtree = key; - goto descend; - } - } - - /* the keyring we're looking at was disqualified or didn't contain a - * matching key */ -not_this_keyring: - if (sp > 0) { - /* resume the checking of a keyring higher up in the tree */ - sp--; - keylist = stack[sp].keylist; - kix = stack[sp].kix + 1; - goto ascend; - } - - ret = 0; /* no cycles detected */ - -error: + search_nested_keyrings(B, &ctx); rcu_read_unlock(); - return ret; - -too_deep: - ret = -ELOOP; - goto error; - -cycle_detected: - ret = -EDEADLK; - goto error; -} - -/* - * Dispose of a keyring list after the RCU grace period, freeing the unlinked - * key - */ -static void keyring_unlink_rcu_disposal(struct rcu_head *rcu) -{ - struct keyring_list *klist = - container_of(rcu, struct keyring_list, rcu); - - if (klist->delkey != USHRT_MAX) - key_put(rcu_access_pointer(klist->keys[klist->delkey])); - kfree(klist); + return PTR_ERR(ctx.result) == -EAGAIN ? 0 : PTR_ERR(ctx.result); } /* * Preallocate memory so that a key can be linked into to a keyring. */ -int __key_link_begin(struct key *keyring, const struct key_type *type, - const char *description, unsigned long *_prealloc) +int __key_link_begin(struct key *keyring, + const struct keyring_index_key *index_key, + struct assoc_array_edit **_edit) __acquires(&keyring->sem) __acquires(&keyring_serialise_link_sem) { - struct keyring_list *klist, *nklist; - unsigned long prealloc; - unsigned max; - time_t lowest_lru; - size_t size; - int loop, lru, ret; + struct assoc_array_edit *edit; + int ret; + + kenter("%d,%s,%s,", + keyring->serial, index_key->type->name, index_key->description); - kenter("%d,%s,%s,", key_serial(keyring), type->name, description); + BUG_ON(index_key->desc_len == 0); if (keyring->type != &key_type_keyring) return -ENOTDIR; @@ -771,91 +1059,28 @@ int __key_link_begin(struct key *keyring, const struct key_type *type, /* serialise link/link calls to prevent parallel calls causing a cycle * when linking two keyring in opposite orders */ - if (type == &key_type_keyring) + if (index_key->type == &key_type_keyring) down_write(&keyring_serialise_link_sem); - klist = rcu_dereference_locked_keyring(keyring); - - /* see if there's a matching key we can displace */ - lru = -1; - if (klist && klist->nkeys > 0) { - lowest_lru = TIME_T_MAX; - for (loop = klist->nkeys - 1; loop >= 0; loop--) { - struct key *key = rcu_deref_link_locked(klist, loop, - keyring); - if (key->type == type && - strcmp(key->description, description) == 0) { - /* Found a match - we'll replace the link with - * one to the new key. We record the slot - * position. - */ - klist->delkey = loop; - prealloc = 0; - goto done; - } - if (key->last_used_at < lowest_lru) { - lowest_lru = key->last_used_at; - lru = loop; - } - } - } - - /* If the keyring is full then do an LRU discard */ - if (klist && - klist->nkeys == klist->maxkeys && - klist->maxkeys >= MAX_KEYRING_LINKS) { - kdebug("LRU discard %d\n", lru); - klist->delkey = lru; - prealloc = 0; - goto done; - } - /* check that we aren't going to overrun the user's quota */ ret = key_payload_reserve(keyring, keyring->datalen + KEYQUOTA_LINK_BYTES); if (ret < 0) goto error_sem; - if (klist && klist->nkeys < klist->maxkeys) { - /* there's sufficient slack space to append directly */ - klist->delkey = klist->nkeys; - prealloc = KEY_LINK_FIXQUOTA; - } else { - /* grow the key list */ - max = 4; - if (klist) { - max += klist->maxkeys; - if (max > MAX_KEYRING_LINKS) - max = MAX_KEYRING_LINKS; - BUG_ON(max <= klist->maxkeys); - } - - size = sizeof(*klist) + sizeof(struct key *) * max; - - ret = -ENOMEM; - nklist = kmalloc(size, GFP_KERNEL); - if (!nklist) - goto error_quota; - - nklist->maxkeys = max; - if (klist) { - memcpy(nklist->keys, klist->keys, - sizeof(struct key *) * klist->nkeys); - nklist->delkey = klist->nkeys; - nklist->nkeys = klist->nkeys + 1; - klist->delkey = USHRT_MAX; - } else { - nklist->nkeys = 1; - nklist->delkey = 0; - } - - /* add the key into the new space */ - RCU_INIT_POINTER(nklist->keys[nklist->delkey], NULL); - prealloc = (unsigned long)nklist | KEY_LINK_FIXQUOTA; + /* Create an edit script that will insert/replace the key in the + * keyring tree. + */ + edit = assoc_array_insert(&keyring->keys, + &keyring_assoc_array_ops, + index_key, + NULL); + if (IS_ERR(edit)) { + ret = PTR_ERR(edit); + goto error_quota; } -done: - *_prealloc = prealloc; + *_edit = edit; kleave(" = 0"); return 0; @@ -864,7 +1089,7 @@ error_quota: key_payload_reserve(keyring, keyring->datalen - KEYQUOTA_LINK_BYTES); error_sem: - if (type == &key_type_keyring) + if (index_key->type == &key_type_keyring) up_write(&keyring_serialise_link_sem); error_krsem: up_write(&keyring->sem); @@ -895,60 +1120,12 @@ int __key_link_check_live_key(struct key *keyring, struct key *key) * holds at most one link to any given key of a particular type+description * combination. */ -void __key_link(struct key *keyring, struct key *key, - unsigned long *_prealloc) +void __key_link(struct key *key, struct assoc_array_edit **_edit) { - struct keyring_list *klist, *nklist; - struct key *discard; - - nklist = (struct keyring_list *)(*_prealloc & ~KEY_LINK_FIXQUOTA); - *_prealloc = 0; - - kenter("%d,%d,%p", keyring->serial, key->serial, nklist); - - klist = rcu_dereference_locked_keyring(keyring); - - atomic_inc(&key->usage); - keyring->last_used_at = key->last_used_at = - current_kernel_time().tv_sec; - - /* there's a matching key we can displace or an empty slot in a newly - * allocated list we can fill */ - if (nklist) { - kdebug("reissue %hu/%hu/%hu", - nklist->delkey, nklist->nkeys, nklist->maxkeys); - - RCU_INIT_POINTER(nklist->keys[nklist->delkey], key); - - rcu_assign_pointer(keyring->payload.subscriptions, nklist); - - /* dispose of the old keyring list and, if there was one, the - * displaced key */ - if (klist) { - kdebug("dispose %hu/%hu/%hu", - klist->delkey, klist->nkeys, klist->maxkeys); - call_rcu(&klist->rcu, keyring_unlink_rcu_disposal); - } - } else if (klist->delkey < klist->nkeys) { - kdebug("replace %hu/%hu/%hu", - klist->delkey, klist->nkeys, klist->maxkeys); - - discard = rcu_dereference_protected( - klist->keys[klist->delkey], - rwsem_is_locked(&keyring->sem)); - rcu_assign_pointer(klist->keys[klist->delkey], key); - /* The garbage collector will take care of RCU - * synchronisation */ - key_put(discard); - } else { - /* there's sufficient slack space to append directly */ - kdebug("append %hu/%hu/%hu", - klist->delkey, klist->nkeys, klist->maxkeys); - - RCU_INIT_POINTER(klist->keys[klist->delkey], key); - smp_wmb(); - klist->nkeys++; - } + __key_get(key); + assoc_array_insert_set_object(*_edit, keyring_key_to_ptr(key)); + assoc_array_apply_edit(*_edit); + *_edit = NULL; } /* @@ -956,24 +1133,22 @@ void __key_link(struct key *keyring, struct key *key, * * Must be called with __key_link_begin() having being called. */ -void __key_link_end(struct key *keyring, struct key_type *type, - unsigned long prealloc) +void __key_link_end(struct key *keyring, + const struct keyring_index_key *index_key, + struct assoc_array_edit *edit) __releases(&keyring->sem) __releases(&keyring_serialise_link_sem) { - BUG_ON(type == NULL); - BUG_ON(type->name == NULL); - kenter("%d,%s,%lx", keyring->serial, type->name, prealloc); + BUG_ON(index_key->type == NULL); + kenter("%d,%s,", keyring->serial, index_key->type->name); - if (type == &key_type_keyring) + if (index_key->type == &key_type_keyring) up_write(&keyring_serialise_link_sem); - if (prealloc) { - if (prealloc & KEY_LINK_FIXQUOTA) - key_payload_reserve(keyring, - keyring->datalen - - KEYQUOTA_LINK_BYTES); - kfree((struct keyring_list *)(prealloc & ~KEY_LINK_FIXQUOTA)); + if (edit) { + key_payload_reserve(keyring, + keyring->datalen - KEYQUOTA_LINK_BYTES); + assoc_array_cancel_edit(edit); } up_write(&keyring->sem); } @@ -1000,20 +1175,28 @@ void __key_link_end(struct key *keyring, struct key_type *type, */ int key_link(struct key *keyring, struct key *key) { - unsigned long prealloc; + struct assoc_array_edit *edit; int ret; + kenter("{%d,%d}", keyring->serial, atomic_read(&keyring->usage)); + key_check(keyring); key_check(key); - ret = __key_link_begin(keyring, key->type, key->description, &prealloc); + if (test_bit(KEY_FLAG_TRUSTED_ONLY, &keyring->flags) && + !test_bit(KEY_FLAG_TRUSTED, &key->flags)) + return -EPERM; + + ret = __key_link_begin(keyring, &key->index_key, &edit); if (ret == 0) { + kdebug("begun {%d,%d}", keyring->serial, atomic_read(&keyring->usage)); ret = __key_link_check_live_key(keyring, key); if (ret == 0) - __key_link(keyring, key, &prealloc); - __key_link_end(keyring, key->type, prealloc); + __key_link(key, &edit); + __key_link_end(keyring, &key->index_key, edit); } + kleave(" = %d {%d,%d}", ret, keyring->serial, atomic_read(&keyring->usage)); return ret; } EXPORT_SYMBOL(key_link); @@ -1037,90 +1220,36 @@ EXPORT_SYMBOL(key_link); */ int key_unlink(struct key *keyring, struct key *key) { - struct keyring_list *klist, *nklist; - int loop, ret; + struct assoc_array_edit *edit; + int ret; key_check(keyring); key_check(key); - ret = -ENOTDIR; if (keyring->type != &key_type_keyring) - goto error; + return -ENOTDIR; down_write(&keyring->sem); - klist = rcu_dereference_locked_keyring(keyring); - if (klist) { - /* search the keyring for the key */ - for (loop = 0; loop < klist->nkeys; loop++) - if (rcu_access_pointer(klist->keys[loop]) == key) - goto key_is_present; + edit = assoc_array_delete(&keyring->keys, &keyring_assoc_array_ops, + &key->index_key); + if (IS_ERR(edit)) { + ret = PTR_ERR(edit); + goto error; } - - up_write(&keyring->sem); ret = -ENOENT; - goto error; - -key_is_present: - /* we need to copy the key list for RCU purposes */ - nklist = kmalloc(sizeof(*klist) + - sizeof(struct key *) * klist->maxkeys, - GFP_KERNEL); - if (!nklist) - goto nomem; - nklist->maxkeys = klist->maxkeys; - nklist->nkeys = klist->nkeys - 1; - - if (loop > 0) - memcpy(&nklist->keys[0], - &klist->keys[0], - loop * sizeof(struct key *)); - - if (loop < nklist->nkeys) - memcpy(&nklist->keys[loop], - &klist->keys[loop + 1], - (nklist->nkeys - loop) * sizeof(struct key *)); - - /* adjust the user's quota */ - key_payload_reserve(keyring, - keyring->datalen - KEYQUOTA_LINK_BYTES); - - rcu_assign_pointer(keyring->payload.subscriptions, nklist); - - up_write(&keyring->sem); - - /* schedule for later cleanup */ - klist->delkey = loop; - call_rcu(&klist->rcu, keyring_unlink_rcu_disposal); + if (edit == NULL) + goto error; + assoc_array_apply_edit(edit); ret = 0; error: - return ret; -nomem: - ret = -ENOMEM; up_write(&keyring->sem); - goto error; + return ret; } EXPORT_SYMBOL(key_unlink); -/* - * Dispose of a keyring list after the RCU grace period, releasing the keys it - * links to. - */ -static void keyring_clear_rcu_disposal(struct rcu_head *rcu) -{ - struct keyring_list *klist; - int loop; - - klist = container_of(rcu, struct keyring_list, rcu); - - for (loop = klist->nkeys - 1; loop >= 0; loop--) - key_put(rcu_access_pointer(klist->keys[loop])); - - kfree(klist); -} - /** * keyring_clear - Clear a keyring * @keyring: The keyring to clear. @@ -1131,33 +1260,25 @@ static void keyring_clear_rcu_disposal(struct rcu_head *rcu) */ int keyring_clear(struct key *keyring) { - struct keyring_list *klist; + struct assoc_array_edit *edit; int ret; - ret = -ENOTDIR; - if (keyring->type == &key_type_keyring) { - /* detach the pointer block with the locks held */ - down_write(&keyring->sem); - - klist = rcu_dereference_locked_keyring(keyring); - if (klist) { - /* adjust the quota */ - key_payload_reserve(keyring, - sizeof(struct keyring_list)); - - rcu_assign_pointer(keyring->payload.subscriptions, - NULL); - } - - up_write(&keyring->sem); + if (keyring->type != &key_type_keyring) + return -ENOTDIR; - /* free the keys after the locks have been dropped */ - if (klist) - call_rcu(&klist->rcu, keyring_clear_rcu_disposal); + down_write(&keyring->sem); + edit = assoc_array_clear(&keyring->keys, &keyring_assoc_array_ops); + if (IS_ERR(edit)) { + ret = PTR_ERR(edit); + } else { + if (edit) + assoc_array_apply_edit(edit); + key_payload_reserve(keyring, 0); ret = 0; } + up_write(&keyring->sem); return ret; } EXPORT_SYMBOL(keyring_clear); @@ -1169,17 +1290,25 @@ EXPORT_SYMBOL(keyring_clear); */ static void keyring_revoke(struct key *keyring) { - struct keyring_list *klist; + struct assoc_array_edit *edit; - klist = rcu_dereference_locked_keyring(keyring); + edit = assoc_array_clear(&keyring->keys, &keyring_assoc_array_ops); + if (!IS_ERR(edit)) { + if (edit) + assoc_array_apply_edit(edit); + key_payload_reserve(keyring, 0); + } +} - /* adjust the quota */ - key_payload_reserve(keyring, 0); +static bool gc_iterator(void *object, void *iterator_data) +{ + struct key *key = keyring_ptr_to_key(object); + time_t *limit = iterator_data; - if (klist) { - rcu_assign_pointer(keyring->payload.subscriptions, NULL); - call_rcu(&klist->rcu, keyring_clear_rcu_disposal); - } + if (key_is_dead(key, *limit)) + return false; + key_get(key); + return true; } /* @@ -1192,88 +1321,12 @@ static void keyring_revoke(struct key *keyring) */ void keyring_gc(struct key *keyring, time_t limit) { - struct keyring_list *klist, *new; - struct key *key; - int loop, keep, max; - kenter("{%x,%s}", key_serial(keyring), keyring->description); down_write(&keyring->sem); - - klist = rcu_dereference_locked_keyring(keyring); - if (!klist) - goto no_klist; - - /* work out how many subscriptions we're keeping */ - keep = 0; - for (loop = klist->nkeys - 1; loop >= 0; loop--) - if (!key_is_dead(rcu_deref_link_locked(klist, loop, keyring), - limit)) - keep++; - - if (keep == klist->nkeys) - goto just_return; - - /* allocate a new keyring payload */ - max = roundup(keep, 4); - new = kmalloc(sizeof(struct keyring_list) + max * sizeof(struct key *), - GFP_KERNEL); - if (!new) - goto nomem; - new->maxkeys = max; - new->nkeys = 0; - new->delkey = 0; - - /* install the live keys - * - must take care as expired keys may be updated back to life - */ - keep = 0; - for (loop = klist->nkeys - 1; loop >= 0; loop--) { - key = rcu_deref_link_locked(klist, loop, keyring); - if (!key_is_dead(key, limit)) { - if (keep >= max) - goto discard_new; - RCU_INIT_POINTER(new->keys[keep++], key_get(key)); - } - } - new->nkeys = keep; - - /* adjust the quota */ - key_payload_reserve(keyring, - sizeof(struct keyring_list) + - KEYQUOTA_LINK_BYTES * keep); - - if (keep == 0) { - rcu_assign_pointer(keyring->payload.subscriptions, NULL); - kfree(new); - } else { - rcu_assign_pointer(keyring->payload.subscriptions, new); - } - - up_write(&keyring->sem); - - call_rcu(&klist->rcu, keyring_clear_rcu_disposal); - kleave(" [yes]"); - return; - -discard_new: - new->nkeys = keep; - keyring_clear_rcu_disposal(&new->rcu); + assoc_array_gc(&keyring->keys, &keyring_assoc_array_ops, + gc_iterator, &limit); up_write(&keyring->sem); - kleave(" [discard]"); - return; -just_return: - up_write(&keyring->sem); - kleave(" [no dead]"); - return; - -no_klist: - up_write(&keyring->sem); - kleave(" [no_klist]"); - return; - -nomem: - up_write(&keyring->sem); - kleave(" [oom]"); + kleave(""); } diff --git a/security/keys/persistent.c b/security/keys/persistent.c new file mode 100644 index 0000000..82f4957a --- /dev/null +++ b/security/keys/persistent.c @@ -0,0 +1,169 @@ +/* General persistent per-UID keyrings register + * + * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include <linux/user_namespace.h> +#include "internal.h" + +unsigned persistent_keyring_expiry = 3 * 24 * 3600; /* Expire after 3 days of non-use */ + +/* + * Create the persistent keyring register for the current user namespace. + * + * Called with the namespace's sem locked for writing. + */ +static int key_create_persistent_register(struct user_namespace *ns) +{ + struct key *reg = keyring_alloc(".persistent_register", + KUIDT_INIT(0), KGIDT_INIT(0), + current_cred(), + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA, NULL); + if (IS_ERR(reg)) + return PTR_ERR(reg); + + ns->persistent_keyring_register = reg; + return 0; +} + +/* + * Create the persistent keyring for the specified user. + * + * Called with the namespace's sem locked for writing. + */ +static key_ref_t key_create_persistent(struct user_namespace *ns, kuid_t uid, + struct keyring_index_key *index_key) +{ + struct key *persistent; + key_ref_t reg_ref, persistent_ref; + + if (!ns->persistent_keyring_register) { + long err = key_create_persistent_register(ns); + if (err < 0) + return ERR_PTR(err); + } else { + reg_ref = make_key_ref(ns->persistent_keyring_register, true); + persistent_ref = find_key_to_update(reg_ref, index_key); + if (persistent_ref) + return persistent_ref; + } + + persistent = keyring_alloc(index_key->description, + uid, INVALID_GID, current_cred(), + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA, + ns->persistent_keyring_register); + if (IS_ERR(persistent)) + return ERR_CAST(persistent); + + return make_key_ref(persistent, true); +} + +/* + * Get the persistent keyring for a specific UID and link it to the nominated + * keyring. + */ +static long key_get_persistent(struct user_namespace *ns, kuid_t uid, + key_ref_t dest_ref) +{ + struct keyring_index_key index_key; + struct key *persistent; + key_ref_t reg_ref, persistent_ref; + char buf[32]; + long ret; + + /* Look in the register if it exists */ + index_key.type = &key_type_keyring; + index_key.description = buf; + index_key.desc_len = sprintf(buf, "_persistent.%u", from_kuid(ns, uid)); + + if (ns->persistent_keyring_register) { + reg_ref = make_key_ref(ns->persistent_keyring_register, true); + down_read(&ns->persistent_keyring_register_sem); + persistent_ref = find_key_to_update(reg_ref, &index_key); + up_read(&ns->persistent_keyring_register_sem); + + if (persistent_ref) + goto found; + } + + /* It wasn't in the register, so we'll need to create it. We might + * also need to create the register. + */ + down_write(&ns->persistent_keyring_register_sem); + persistent_ref = key_create_persistent(ns, uid, &index_key); + up_write(&ns->persistent_keyring_register_sem); + if (!IS_ERR(persistent_ref)) + goto found; + + return PTR_ERR(persistent_ref); + +found: + ret = key_task_permission(persistent_ref, current_cred(), KEY_LINK); + if (ret == 0) { + persistent = key_ref_to_ptr(persistent_ref); + ret = key_link(key_ref_to_ptr(dest_ref), persistent); + if (ret == 0) { + key_set_timeout(persistent, persistent_keyring_expiry); + ret = persistent->serial; + } + } + + key_ref_put(persistent_ref); + return ret; +} + +/* + * Get the persistent keyring for a specific UID and link it to the nominated + * keyring. + */ +long keyctl_get_persistent(uid_t _uid, key_serial_t destid) +{ + struct user_namespace *ns = current_user_ns(); + key_ref_t dest_ref; + kuid_t uid; + long ret; + + /* -1 indicates the current user */ + if (_uid == (uid_t)-1) { + uid = current_uid(); + } else { + uid = make_kuid(ns, _uid); + if (!uid_valid(uid)) + return -EINVAL; + + /* You can only see your own persistent cache if you're not + * sufficiently privileged. + */ + if (uid_eq(uid, current_uid()) && + uid_eq(uid, current_suid()) && + uid_eq(uid, current_euid()) && + uid_eq(uid, current_fsuid()) && + !ns_capable(ns, CAP_SETUID)) + return -EPERM; + } + + /* There must be a destination keyring */ + dest_ref = lookup_user_key(destid, KEY_LOOKUP_CREATE, KEY_WRITE); + if (IS_ERR(dest_ref)) + return PTR_ERR(dest_ref); + if (key_ref_to_ptr(dest_ref)->type != &key_type_keyring) { + ret = -ENOTDIR; + goto out_put_dest; + } + + ret = key_get_persistent(ns, uid, dest_ref); + +out_put_dest: + key_ref_put(dest_ref); + return ret; +} diff --git a/security/keys/proc.c b/security/keys/proc.c index 217b685..88e9a46 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -182,7 +182,6 @@ static void proc_keys_stop(struct seq_file *p, void *v) static int proc_keys_show(struct seq_file *m, void *v) { - const struct cred *cred = current_cred(); struct rb_node *_p = v; struct key *key = rb_entry(_p, struct key, serial_node); struct timespec now; @@ -191,15 +190,23 @@ static int proc_keys_show(struct seq_file *m, void *v) char xbuf[12]; int rc; + struct keyring_search_context ctx = { + .index_key.type = key->type, + .index_key.description = key->description, + .cred = current_cred(), + .match = lookup_user_key_possessed, + .match_data = key, + .flags = (KEYRING_SEARCH_NO_STATE_CHECK | + KEYRING_SEARCH_LOOKUP_DIRECT), + }; + key_ref = make_key_ref(key, 0); /* determine if the key is possessed by this process (a test we can * skip if the key does not indicate the possessor can view it */ if (key->perm & KEY_POS_VIEW) { - skey_ref = search_my_process_keyrings(key->type, key, - lookup_user_key_possessed, - true, cred); + skey_ref = search_my_process_keyrings(&ctx); if (!IS_ERR(skey_ref)) { key_ref_put(skey_ref); key_ref = make_key_ref(key, 1); @@ -211,7 +218,7 @@ static int proc_keys_show(struct seq_file *m, void *v) * - the caller holds a spinlock, and thus the RCU read lock, making our * access to __current_cred() safe */ - rc = key_task_permission(key_ref, cred, KEY_VIEW); + rc = key_task_permission(key_ref, ctx.cred, KEY_VIEW); if (rc < 0) return 0; diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 42defae..0cf8a13 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -235,7 +235,7 @@ int install_session_keyring_to_cred(struct cred *cred, struct key *keyring) if (IS_ERR(keyring)) return PTR_ERR(keyring); } else { - atomic_inc(&keyring->usage); + __key_get(keyring); } /* install the keyring */ @@ -319,11 +319,7 @@ void key_fsgid_changed(struct task_struct *tsk) * In the case of a successful return, the possession attribute is set on the * returned key reference. */ -key_ref_t search_my_process_keyrings(struct key_type *type, - const void *description, - key_match_func_t match, - bool no_state_check, - const struct cred *cred) +key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx) { key_ref_t key_ref, ret, err; @@ -339,10 +335,9 @@ key_ref_t search_my_process_keyrings(struct key_type *type, err = ERR_PTR(-EAGAIN); /* search the thread keyring first */ - if (cred->thread_keyring) { + if (ctx->cred->thread_keyring) { key_ref = keyring_search_aux( - make_key_ref(cred->thread_keyring, 1), - cred, type, description, match, no_state_check); + make_key_ref(ctx->cred->thread_keyring, 1), ctx); if (!IS_ERR(key_ref)) goto found; @@ -358,10 +353,9 @@ key_ref_t search_my_process_keyrings(struct key_type *type, } /* search the process keyring second */ - if (cred->process_keyring) { + if (ctx->cred->process_keyring) { key_ref = keyring_search_aux( - make_key_ref(cred->process_keyring, 1), - cred, type, description, match, no_state_check); + make_key_ref(ctx->cred->process_keyring, 1), ctx); if (!IS_ERR(key_ref)) goto found; @@ -379,11 +373,11 @@ key_ref_t search_my_process_keyrings(struct key_type *type, } /* search the session keyring */ - if (cred->session_keyring) { + if (ctx->cred->session_keyring) { rcu_read_lock(); key_ref = keyring_search_aux( - make_key_ref(rcu_dereference(cred->session_keyring), 1), - cred, type, description, match, no_state_check); + make_key_ref(rcu_dereference(ctx->cred->session_keyring), 1), + ctx); rcu_read_unlock(); if (!IS_ERR(key_ref)) @@ -402,10 +396,10 @@ key_ref_t search_my_process_keyrings(struct key_type *type, } } /* or search the user-session keyring */ - else if (cred->user->session_keyring) { + else if (ctx->cred->user->session_keyring) { key_ref = keyring_search_aux( - make_key_ref(cred->user->session_keyring, 1), - cred, type, description, match, no_state_check); + make_key_ref(ctx->cred->user->session_keyring, 1), + ctx); if (!IS_ERR(key_ref)) goto found; @@ -437,18 +431,14 @@ found: * * Return same as search_my_process_keyrings(). */ -key_ref_t search_process_keyrings(struct key_type *type, - const void *description, - key_match_func_t match, - const struct cred *cred) +key_ref_t search_process_keyrings(struct keyring_search_context *ctx) { struct request_key_auth *rka; key_ref_t key_ref, ret = ERR_PTR(-EACCES), err; might_sleep(); - key_ref = search_my_process_keyrings(type, description, match, - false, cred); + key_ref = search_my_process_keyrings(ctx); if (!IS_ERR(key_ref)) goto found; err = key_ref; @@ -457,18 +447,21 @@ key_ref_t search_process_keyrings(struct key_type *type, * search the keyrings of the process mentioned there * - we don't permit access to request_key auth keys via this method */ - if (cred->request_key_auth && - cred == current_cred() && - type != &key_type_request_key_auth + if (ctx->cred->request_key_auth && + ctx->cred == current_cred() && + ctx->index_key.type != &key_type_request_key_auth ) { + const struct cred *cred = ctx->cred; + /* defend against the auth key being revoked */ down_read(&cred->request_key_auth->sem); - if (key_validate(cred->request_key_auth) == 0) { - rka = cred->request_key_auth->payload.data; + if (key_validate(ctx->cred->request_key_auth) == 0) { + rka = ctx->cred->request_key_auth->payload.data; - key_ref = search_process_keyrings(type, description, - match, rka->cred); + ctx->cred = rka->cred; + key_ref = search_process_keyrings(ctx); + ctx->cred = cred; up_read(&cred->request_key_auth->sem); @@ -522,19 +515,23 @@ int lookup_user_key_possessed(const struct key *key, const void *target) key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags, key_perm_t perm) { + struct keyring_search_context ctx = { + .match = lookup_user_key_possessed, + .flags = (KEYRING_SEARCH_NO_STATE_CHECK | + KEYRING_SEARCH_LOOKUP_DIRECT), + }; struct request_key_auth *rka; - const struct cred *cred; struct key *key; key_ref_t key_ref, skey_ref; int ret; try_again: - cred = get_current_cred(); + ctx.cred = get_current_cred(); key_ref = ERR_PTR(-ENOKEY); switch (id) { case KEY_SPEC_THREAD_KEYRING: - if (!cred->thread_keyring) { + if (!ctx.cred->thread_keyring) { if (!(lflags & KEY_LOOKUP_CREATE)) goto error; @@ -546,13 +543,13 @@ try_again: goto reget_creds; } - key = cred->thread_keyring; - atomic_inc(&key->usage); + key = ctx.cred->thread_keyring; + __key_get(key); key_ref = make_key_ref(key, 1); break; case KEY_SPEC_PROCESS_KEYRING: - if (!cred->process_keyring) { + if (!ctx.cred->process_keyring) { if (!(lflags & KEY_LOOKUP_CREATE)) goto error; @@ -564,13 +561,13 @@ try_again: goto reget_creds; } - key = cred->process_keyring; - atomic_inc(&key->usage); + key = ctx.cred->process_keyring; + __key_get(key); key_ref = make_key_ref(key, 1); break; case KEY_SPEC_SESSION_KEYRING: - if (!cred->session_keyring) { + if (!ctx.cred->session_keyring) { /* always install a session keyring upon access if one * doesn't exist yet */ ret = install_user_keyrings(); @@ -580,13 +577,13 @@ try_again: ret = join_session_keyring(NULL); else ret = install_session_keyring( - cred->user->session_keyring); + ctx.cred->user->session_keyring); if (ret < 0) goto error; goto reget_creds; - } else if (cred->session_keyring == - cred->user->session_keyring && + } else if (ctx.cred->session_keyring == + ctx.cred->user->session_keyring && lflags & KEY_LOOKUP_CREATE) { ret = join_session_keyring(NULL); if (ret < 0) @@ -595,33 +592,33 @@ try_again: } rcu_read_lock(); - key = rcu_dereference(cred->session_keyring); - atomic_inc(&key->usage); + key = rcu_dereference(ctx.cred->session_keyring); + __key_get(key); rcu_read_unlock(); key_ref = make_key_ref(key, 1); break; case KEY_SPEC_USER_KEYRING: - if (!cred->user->uid_keyring) { + if (!ctx.cred->user->uid_keyring) { ret = install_user_keyrings(); if (ret < 0) goto error; } - key = cred->user->uid_keyring; - atomic_inc(&key->usage); + key = ctx.cred->user->uid_keyring; + __key_get(key); key_ref = make_key_ref(key, 1); break; case KEY_SPEC_USER_SESSION_KEYRING: - if (!cred->user->session_keyring) { + if (!ctx.cred->user->session_keyring) { ret = install_user_keyrings(); if (ret < 0) goto error; } - key = cred->user->session_keyring; - atomic_inc(&key->usage); + key = ctx.cred->user->session_keyring; + __key_get(key); key_ref = make_key_ref(key, 1); break; @@ -631,29 +628,29 @@ try_again: goto error; case KEY_SPEC_REQKEY_AUTH_KEY: - key = cred->request_key_auth; + key = ctx.cred->request_key_auth; if (!key) goto error; - atomic_inc(&key->usage); + __key_get(key); key_ref = make_key_ref(key, 1); break; case KEY_SPEC_REQUESTOR_KEYRING: - if (!cred->request_key_auth) + if (!ctx.cred->request_key_auth) goto error; - down_read(&cred->request_key_auth->sem); + down_read(&ctx.cred->request_key_auth->sem); if (test_bit(KEY_FLAG_REVOKED, - &cred->request_key_auth->flags)) { + &ctx.cred->request_key_auth->flags)) { key_ref = ERR_PTR(-EKEYREVOKED); key = NULL; } else { - rka = cred->request_key_auth->payload.data; + rka = ctx.cred->request_key_auth->payload.data; key = rka->dest_keyring; - atomic_inc(&key->usage); + __key_get(key); } - up_read(&cred->request_key_auth->sem); + up_read(&ctx.cred->request_key_auth->sem); if (!key) goto error; key_ref = make_key_ref(key, 1); @@ -673,9 +670,13 @@ try_again: key_ref = make_key_ref(key, 0); /* check to see if we possess the key */ - skey_ref = search_process_keyrings(key->type, key, - lookup_user_key_possessed, - cred); + ctx.index_key.type = key->type; + ctx.index_key.description = key->description; + ctx.index_key.desc_len = strlen(key->description); + ctx.match_data = key; + kdebug("check possessed"); + skey_ref = search_process_keyrings(&ctx); + kdebug("possessed=%p", skey_ref); if (!IS_ERR(skey_ref)) { key_put(key); @@ -715,14 +716,14 @@ try_again: goto invalid_key; /* check the permissions */ - ret = key_task_permission(key_ref, cred, perm); + ret = key_task_permission(key_ref, ctx.cred, perm); if (ret < 0) goto invalid_key; key->last_used_at = current_kernel_time().tv_sec; error: - put_cred(cred); + put_cred(ctx.cred); return key_ref; invalid_key: @@ -733,7 +734,7 @@ invalid_key: /* if we attempted to install a keyring, then it may have caused new * creds to be installed */ reget_creds: - put_cred(cred); + put_cred(ctx.cred); goto try_again; } @@ -856,3 +857,13 @@ void key_change_session_keyring(struct callback_head *twork) commit_creds(new); } + +/* + * Make sure that root's user and user-session keyrings exist. + */ +static int __init init_root_keyring(void) +{ + return install_user_keyrings(); +} + +late_initcall(init_root_keyring); diff --git a/security/keys/request_key.c b/security/keys/request_key.c index c411f9b..df94827 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -345,33 +345,34 @@ static void construct_get_dest_keyring(struct key **_dest_keyring) * May return a key that's already under construction instead if there was a * race between two thread calling request_key(). */ -static int construct_alloc_key(struct key_type *type, - const char *description, +static int construct_alloc_key(struct keyring_search_context *ctx, struct key *dest_keyring, unsigned long flags, struct key_user *user, struct key **_key) { - const struct cred *cred = current_cred(); - unsigned long prealloc; + struct assoc_array_edit *edit; struct key *key; key_perm_t perm; key_ref_t key_ref; int ret; - kenter("%s,%s,,,", type->name, description); + kenter("%s,%s,,,", + ctx->index_key.type->name, ctx->index_key.description); *_key = NULL; mutex_lock(&user->cons_lock); perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; perm |= KEY_USR_VIEW; - if (type->read) + if (ctx->index_key.type->read) perm |= KEY_POS_READ; - if (type == &key_type_keyring || type->update) + if (ctx->index_key.type == &key_type_keyring || + ctx->index_key.type->update) perm |= KEY_POS_WRITE; - key = key_alloc(type, description, cred->fsuid, cred->fsgid, cred, + key = key_alloc(ctx->index_key.type, ctx->index_key.description, + ctx->cred->fsuid, ctx->cred->fsgid, ctx->cred, perm, flags); if (IS_ERR(key)) goto alloc_failed; @@ -379,8 +380,7 @@ static int construct_alloc_key(struct key_type *type, set_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags); if (dest_keyring) { - ret = __key_link_begin(dest_keyring, type, description, - &prealloc); + ret = __key_link_begin(dest_keyring, &ctx->index_key, &edit); if (ret < 0) goto link_prealloc_failed; } @@ -390,16 +390,16 @@ static int construct_alloc_key(struct key_type *type, * waited for locks */ mutex_lock(&key_construction_mutex); - key_ref = search_process_keyrings(type, description, type->match, cred); + key_ref = search_process_keyrings(ctx); if (!IS_ERR(key_ref)) goto key_already_present; if (dest_keyring) - __key_link(dest_keyring, key, &prealloc); + __key_link(key, &edit); mutex_unlock(&key_construction_mutex); if (dest_keyring) - __key_link_end(dest_keyring, type, prealloc); + __key_link_end(dest_keyring, &ctx->index_key, edit); mutex_unlock(&user->cons_lock); *_key = key; kleave(" = 0 [%d]", key_serial(key)); @@ -414,8 +414,8 @@ key_already_present: if (dest_keyring) { ret = __key_link_check_live_key(dest_keyring, key); if (ret == 0) - __key_link(dest_keyring, key, &prealloc); - __key_link_end(dest_keyring, type, prealloc); + __key_link(key, &edit); + __key_link_end(dest_keyring, &ctx->index_key, edit); if (ret < 0) goto link_check_failed; } @@ -444,8 +444,7 @@ alloc_failed: /* * Commence key construction. */ -static struct key *construct_key_and_link(struct key_type *type, - const char *description, +static struct key *construct_key_and_link(struct keyring_search_context *ctx, const char *callout_info, size_t callout_len, void *aux, @@ -464,8 +463,7 @@ static struct key *construct_key_and_link(struct key_type *type, construct_get_dest_keyring(&dest_keyring); - ret = construct_alloc_key(type, description, dest_keyring, flags, user, - &key); + ret = construct_alloc_key(ctx, dest_keyring, flags, user, &key); key_user_put(user); if (ret == 0) { @@ -529,17 +527,24 @@ struct key *request_key_and_link(struct key_type *type, struct key *dest_keyring, unsigned long flags) { - const struct cred *cred = current_cred(); + struct keyring_search_context ctx = { + .index_key.type = type, + .index_key.description = description, + .cred = current_cred(), + .match = type->match, + .match_data = description, + .flags = KEYRING_SEARCH_LOOKUP_DIRECT, + }; struct key *key; key_ref_t key_ref; int ret; kenter("%s,%s,%p,%zu,%p,%p,%lx", - type->name, description, callout_info, callout_len, aux, - dest_keyring, flags); + ctx.index_key.type->name, ctx.index_key.description, + callout_info, callout_len, aux, dest_keyring, flags); /* search all the process keyrings for a key */ - key_ref = search_process_keyrings(type, description, type->match, cred); + key_ref = search_process_keyrings(&ctx); if (!IS_ERR(key_ref)) { key = key_ref_to_ptr(key_ref); @@ -562,9 +567,8 @@ struct key *request_key_and_link(struct key_type *type, if (!callout_info) goto error; - key = construct_key_and_link(type, description, callout_info, - callout_len, aux, dest_keyring, - flags); + key = construct_key_and_link(&ctx, callout_info, callout_len, + aux, dest_keyring, flags); } error: diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index 85730d5..7495a93 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -18,6 +18,7 @@ #include <linux/slab.h> #include <asm/uaccess.h> #include "internal.h" +#include <keys/user-type.h> static int request_key_auth_instantiate(struct key *, struct key_preparsed_payload *); @@ -222,32 +223,26 @@ error_alloc: } /* - * See if an authorisation key is associated with a particular key. - */ -static int key_get_instantiation_authkey_match(const struct key *key, - const void *_id) -{ - struct request_key_auth *rka = key->payload.data; - key_serial_t id = (key_serial_t)(unsigned long) _id; - - return rka->target_key->serial == id; -} - -/* * Search the current process's keyrings for the authorisation key for * instantiation of a key. */ struct key *key_get_instantiation_authkey(key_serial_t target_id) { - const struct cred *cred = current_cred(); + char description[16]; + struct keyring_search_context ctx = { + .index_key.type = &key_type_request_key_auth, + .index_key.description = description, + .cred = current_cred(), + .match = user_match, + .match_data = description, + .flags = KEYRING_SEARCH_LOOKUP_DIRECT, + }; struct key *authkey; key_ref_t authkey_ref; - authkey_ref = search_process_keyrings( - &key_type_request_key_auth, - (void *) (unsigned long) target_id, - key_get_instantiation_authkey_match, - cred); + sprintf(description, "%x", target_id); + + authkey_ref = search_process_keyrings(&ctx); if (IS_ERR(authkey_ref)) { authkey = ERR_CAST(authkey_ref); diff --git a/security/keys/sysctl.c b/security/keys/sysctl.c index ee32d18..8c0af08 100644 --- a/security/keys/sysctl.c +++ b/security/keys/sysctl.c @@ -61,5 +61,16 @@ ctl_table key_sysctls[] = { .extra1 = (void *) &zero, .extra2 = (void *) &max, }, +#ifdef CONFIG_PERSISTENT_KEYRINGS + { + .procname = "persistent_keyring_expiry", + .data = &persistent_keyring_expiry, + .maxlen = sizeof(unsigned), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = (void *) &zero, + .extra2 = (void *) &max, + }, +#endif { } }; diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c index 55dc889..faa2cae 100644 --- a/security/keys/user_defined.c +++ b/security/keys/user_defined.c @@ -25,14 +25,15 @@ static int logon_vet_description(const char *desc); * arbitrary blob of data as the payload */ struct key_type key_type_user = { - .name = "user", - .instantiate = user_instantiate, - .update = user_update, - .match = user_match, - .revoke = user_revoke, - .destroy = user_destroy, - .describe = user_describe, - .read = user_read, + .name = "user", + .def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, + .instantiate = user_instantiate, + .update = user_update, + .match = user_match, + .revoke = user_revoke, + .destroy = user_destroy, + .describe = user_describe, + .read = user_read, }; EXPORT_SYMBOL_GPL(key_type_user); @@ -45,6 +46,7 @@ EXPORT_SYMBOL_GPL(key_type_user); */ struct key_type key_type_logon = { .name = "logon", + .def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, .instantiate = user_instantiate, .update = user_update, .match = user_match, diff --git a/security/security.c b/security/security.c index 9404802..15b6928 100644 --- a/security/security.c +++ b/security/security.c @@ -348,10 +348,10 @@ int security_inode_init_security(struct inode *inode, struct inode *dir, if (unlikely(IS_PRIVATE(inode))) return 0; - memset(new_xattrs, 0, sizeof new_xattrs); if (!initxattrs) return security_ops->inode_init_security(inode, dir, qstr, NULL, NULL, NULL); + memset(new_xattrs, 0, sizeof(new_xattrs)); lsm_xattr = new_xattrs; ret = security_ops->inode_init_security(inode, dir, qstr, &lsm_xattr->name, @@ -366,16 +366,14 @@ int security_inode_init_security(struct inode *inode, struct inode *dir, goto out; ret = initxattrs(inode, new_xattrs, fs_data); out: - for (xattr = new_xattrs; xattr->name != NULL; xattr++) { - kfree(xattr->name); + for (xattr = new_xattrs; xattr->value != NULL; xattr++) kfree(xattr->value); - } return (ret == -EOPNOTSUPP) ? 0 : ret; } EXPORT_SYMBOL(security_inode_init_security); int security_old_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, char **name, + const struct qstr *qstr, const char **name, void **value, size_t *len) { if (unlikely(IS_PRIVATE(inode))) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index c09211a..6d0bf5c 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2624,7 +2624,8 @@ static int selinux_dentry_init_security(struct dentry *dentry, int mode, } static int selinux_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, char **name, + const struct qstr *qstr, + const char **name, void **value, size_t *len) { const struct task_security_struct *tsec = current_security(); @@ -2632,7 +2633,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, struct superblock_security_struct *sbsec; u32 sid, newsid, clen; int rc; - char *namep = NULL, *context; + char *context; dsec = dir->i_security; sbsec = dir->i_sb->s_security; @@ -2668,19 +2669,13 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) return -EOPNOTSUPP; - if (name) { - namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); - if (!namep) - return -ENOMEM; - *name = namep; - } + if (name) + *name = XATTR_SELINUX_SUFFIX; if (value && len) { rc = security_sid_to_context_force(newsid, &context, &clen); - if (rc) { - kfree(namep); + if (rc) return rc; - } *value = context; *len = clen; } diff --git a/security/selinux/include/xfrm.h b/security/selinux/include/xfrm.h index 7605251..0dec76c 100644 --- a/security/selinux/include/xfrm.h +++ b/security/selinux/include/xfrm.h @@ -42,8 +42,13 @@ int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid, int ckall); static inline void selinux_xfrm_notify_policyload(void) { + struct net *net; + atomic_inc(&flow_cache_genid); - rt_genid_bump(&init_net); + rtnl_lock(); + for_each_net(net) + rt_genid_bump_all(net); + rtnl_unlock(); } #else static inline int selinux_xfrm_enabled(void) diff --git a/security/smack/smack.h b/security/smack/smack.h index 339614c..076b8e8 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -53,6 +53,7 @@ */ struct smack_known { struct list_head list; + struct hlist_node smk_hashed; char *smk_known; u32 smk_secid; struct netlbl_lsm_secattr smk_netlabel; /* on wire labels */ @@ -167,9 +168,13 @@ struct smk_port_label { #define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */ #define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */ #define SMACK_CIPSO_MAPPED_DEFAULT 251 /* Also arbitrary */ -#define SMACK_CIPSO_MAXCATVAL 63 /* Bigger gets harder */ #define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */ -#define SMACK_CIPSO_MAXCATNUM 239 /* CIPSO 2.2 standard */ +/* + * CIPSO 2.2 standard is 239, but Smack wants to use the + * categories in a structured way that limits the value to + * the bits in 23 bytes, hence the unusual number. + */ +#define SMACK_CIPSO_MAXCATNUM 184 /* 23 * 8 */ /* * Flag for transmute access @@ -222,6 +227,7 @@ char *smk_parse_smack(const char *string, int len); int smk_netlbl_mls(int, char *, struct netlbl_lsm_secattr *, int); char *smk_import(const char *, int); struct smack_known *smk_import_entry(const char *, int); +void smk_insert_entry(struct smack_known *skp); struct smack_known *smk_find_entry(const char *); u32 smack_to_secid(const char *); @@ -247,6 +253,9 @@ extern struct list_head smk_netlbladdr_list; extern struct security_operations smack_ops; +#define SMACK_HASH_SLOTS 16 +extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; + /* * Is the directory transmuting? */ diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index 6a0377f..b3b59b1 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -325,6 +325,25 @@ void smack_log(char *subject_label, char *object_label, int request, DEFINE_MUTEX(smack_known_lock); +struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; + +/** + * smk_insert_entry - insert a smack label into a hash map, + * + * this function must be called under smack_known_lock + */ +void smk_insert_entry(struct smack_known *skp) +{ + unsigned int hash; + struct hlist_head *head; + + hash = full_name_hash(skp->smk_known, strlen(skp->smk_known)); + head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)]; + + hlist_add_head_rcu(&skp->smk_hashed, head); + list_add_rcu(&skp->list, &smack_known_list); +} + /** * smk_find_entry - find a label on the list, return the list entry * @string: a text string that might be a Smack label @@ -334,12 +353,16 @@ DEFINE_MUTEX(smack_known_lock); */ struct smack_known *smk_find_entry(const char *string) { + unsigned int hash; + struct hlist_head *head; struct smack_known *skp; - list_for_each_entry_rcu(skp, &smack_known_list, list) { + hash = full_name_hash(string, strlen(string)); + head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)]; + + hlist_for_each_entry_rcu(skp, head, smk_hashed) if (strcmp(skp->smk_known, string) == 0) return skp; - } return NULL; } @@ -475,7 +498,7 @@ struct smack_known *smk_import_entry(const char *string, int len) * Make sure that the entry is actually * filled before putting it on the list. */ - list_add_rcu(&skp->list, &smack_known_list); + smk_insert_entry(skp); goto unlockout; } /* diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index eefbd10..8825375 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -582,7 +582,7 @@ static void smack_inode_free_security(struct inode *inode) * Returns 0 if it all works out, -ENOMEM if there's no memory */ static int smack_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, char **name, + const struct qstr *qstr, const char **name, void **value, size_t *len) { struct inode_smack *issp = inode->i_security; @@ -591,11 +591,8 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, char *dsp = smk_of_inode(dir); int may; - if (name) { - *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_NOFS); - if (*name == NULL) - return -ENOMEM; - } + if (name) + *name = XATTR_SMACK_SUFFIX; if (value) { rcu_read_lock(); @@ -3065,6 +3062,8 @@ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap, { struct smack_known *skp; int found = 0; + int acat; + int kcat; if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) { /* @@ -3081,12 +3080,28 @@ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap, list_for_each_entry(skp, &smack_known_list, list) { if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl) continue; - if (memcmp(sap->attr.mls.cat, - skp->smk_netlabel.attr.mls.cat, - SMK_CIPSOLEN) != 0) - continue; - found = 1; - break; + /* + * Compare the catsets. Use the netlbl APIs. + */ + if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) { + if ((skp->smk_netlabel.flags & + NETLBL_SECATTR_MLS_CAT) == 0) + found = 1; + break; + } + for (acat = -1, kcat = -1; acat == kcat; ) { + acat = netlbl_secattr_catmap_walk( + sap->attr.mls.cat, acat + 1); + kcat = netlbl_secattr_catmap_walk( + skp->smk_netlabel.attr.mls.cat, + kcat + 1); + if (acat < 0 || kcat < 0) + break; + } + if (acat == kcat) { + found = 1; + break; + } } rcu_read_unlock(); @@ -3877,12 +3892,12 @@ static __init void init_smack_known_list(void) /* * Create the known labels list */ - list_add(&smack_known_huh.list, &smack_known_list); - list_add(&smack_known_hat.list, &smack_known_list); - list_add(&smack_known_star.list, &smack_known_list); - list_add(&smack_known_floor.list, &smack_known_list); - list_add(&smack_known_invalid.list, &smack_known_list); - list_add(&smack_known_web.list, &smack_known_list); + smk_insert_entry(&smack_known_huh); + smk_insert_entry(&smack_known_hat); + smk_insert_entry(&smack_known_star); + smk_insert_entry(&smack_known_floor); + smk_insert_entry(&smack_known_invalid); + smk_insert_entry(&smack_known_web); } /** diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index ab16703..80f4b4a 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -368,56 +368,43 @@ static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule, * @data: string to be parsed, null terminated * @rule: Will be filled with Smack parsed rule * @import: if non-zero, import labels - * @change: if non-zero, data is from /smack/change-rule + * @tokens: numer of substrings expected in data * - * Returns 0 on success, -1 on failure + * Returns number of processed bytes on success, -1 on failure. */ -static int smk_parse_long_rule(const char *data, struct smack_parsed_rule *rule, - int import, int change) +static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule, + int import, int tokens) { - char *subject; - char *object; - char *access1; - char *access2; - int datalen; - int rc = -1; + ssize_t cnt = 0; + char *tok[4]; + int i; - /* This is inefficient */ - datalen = strlen(data); + /* + * Parsing the rule in-place, filling all white-spaces with '\0' + */ + for (i = 0; i < tokens; ++i) { + while (isspace(data[cnt])) + data[cnt++] = '\0'; - /* Our first element can be 64 + \0 with no spaces */ - subject = kzalloc(datalen + 1, GFP_KERNEL); - if (subject == NULL) - return -1; - object = kzalloc(datalen, GFP_KERNEL); - if (object == NULL) - goto free_out_s; - access1 = kzalloc(datalen, GFP_KERNEL); - if (access1 == NULL) - goto free_out_o; - access2 = kzalloc(datalen, GFP_KERNEL); - if (access2 == NULL) - goto free_out_a; - - if (change) { - if (sscanf(data, "%s %s %s %s", - subject, object, access1, access2) == 4) - rc = smk_fill_rule(subject, object, access1, access2, - rule, import, 0); - } else { - if (sscanf(data, "%s %s %s", subject, object, access1) == 3) - rc = smk_fill_rule(subject, object, access1, NULL, - rule, import, 0); + if (data[cnt] == '\0') + /* Unexpected end of data */ + return -1; + + tok[i] = data + cnt; + + while (data[cnt] && !isspace(data[cnt])) + ++cnt; } + while (isspace(data[cnt])) + data[cnt++] = '\0'; - kfree(access2); -free_out_a: - kfree(access1); -free_out_o: - kfree(object); -free_out_s: - kfree(subject); - return rc; + while (i < 4) + tok[i++] = NULL; + + if (smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0)) + return -1; + + return cnt; } #define SMK_FIXED24_FMT 0 /* Fixed 24byte label format */ @@ -447,11 +434,12 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf, struct list_head *rule_list, struct mutex *rule_lock, int format) { - struct smack_parsed_rule *rule; + struct smack_parsed_rule rule; char *data; - int datalen; - int rc = -EINVAL; - int load = 0; + int rc; + int trunc = 0; + int tokens; + ssize_t cnt = 0; /* * No partial writes. @@ -466,11 +454,14 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf, */ if (count != SMK_OLOADLEN && count != SMK_LOADLEN) return -EINVAL; - datalen = SMK_LOADLEN; - } else - datalen = count + 1; + } else { + if (count >= PAGE_SIZE) { + count = PAGE_SIZE - 1; + trunc = 1; + } + } - data = kzalloc(datalen, GFP_KERNEL); + data = kmalloc(count + 1, GFP_KERNEL); if (data == NULL) return -ENOMEM; @@ -479,47 +470,49 @@ static ssize_t smk_write_rules_list(struct file *file, const char __user *buf, goto out; } - rule = kzalloc(sizeof(*rule), GFP_KERNEL); - if (rule == NULL) { - rc = -ENOMEM; - goto out; + /* + * In case of parsing only part of user buf, + * avoid having partial rule at the data buffer + */ + if (trunc) { + while (count > 0 && (data[count - 1] != '\n')) + --count; + if (count == 0) { + rc = -EINVAL; + goto out; + } } - if (format == SMK_LONG_FMT) { - /* - * Be sure the data string is terminated. - */ - data[count] = '\0'; - if (smk_parse_long_rule(data, rule, 1, 0)) - goto out_free_rule; - } else if (format == SMK_CHANGE_FMT) { - data[count] = '\0'; - if (smk_parse_long_rule(data, rule, 1, 1)) - goto out_free_rule; - } else { - /* - * More on the minor hack for backward compatibility - */ - if (count == (SMK_OLOADLEN)) - data[SMK_OLOADLEN] = '-'; - if (smk_parse_rule(data, rule, 1)) - goto out_free_rule; - } + data[count] = '\0'; + tokens = (format == SMK_CHANGE_FMT ? 4 : 3); + while (cnt < count) { + if (format == SMK_FIXED24_FMT) { + rc = smk_parse_rule(data, &rule, 1); + if (rc != 0) { + rc = -EINVAL; + goto out; + } + cnt = count; + } else { + rc = smk_parse_long_rule(data + cnt, &rule, 1, tokens); + if (rc <= 0) { + rc = -EINVAL; + goto out; + } + cnt += rc; + } - if (rule_list == NULL) { - load = 1; - rule_list = &rule->smk_subject->smk_rules; - rule_lock = &rule->smk_subject->smk_rules_lock; - } + if (rule_list == NULL) + rc = smk_set_access(&rule, &rule.smk_subject->smk_rules, + &rule.smk_subject->smk_rules_lock, 1); + else + rc = smk_set_access(&rule, rule_list, rule_lock, 0); - rc = smk_set_access(rule, rule_list, rule_lock, load); - if (rc == 0) { - rc = count; - goto out; + if (rc) + goto out; } -out_free_rule: - kfree(rule); + rc = cnt; out: kfree(data); return rc; @@ -901,7 +894,7 @@ static ssize_t smk_set_cipso(struct file *file, const char __user *buf, for (i = 0; i < catlen; i++) { rule += SMK_DIGITLEN; ret = sscanf(rule, "%u", &cat); - if (ret != 1 || cat > SMACK_CIPSO_MAXCATVAL) + if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM) goto out; smack_catset_bit(cat, mapcatset); @@ -1840,7 +1833,6 @@ static ssize_t smk_user_access(struct file *file, const char __user *buf, { struct smack_parsed_rule rule; char *data; - char *cod; int res; data = simple_transaction_get(file, buf, count); @@ -1853,18 +1845,12 @@ static ssize_t smk_user_access(struct file *file, const char __user *buf, res = smk_parse_rule(data, &rule, 0); } else { /* - * Copy the data to make sure the string is terminated. + * simple_transaction_get() returns null-terminated data */ - cod = kzalloc(count + 1, GFP_KERNEL); - if (cod == NULL) - return -ENOMEM; - memcpy(cod, data, count); - cod[count] = '\0'; - res = smk_parse_long_rule(cod, &rule, 0, 0); - kfree(cod); + res = smk_parse_long_rule(data, &rule, 0, 3); } - if (res) + if (res < 0) return -EINVAL; res = smk_access(rule.smk_subject, rule.smk_object, |