diff options
Diffstat (limited to 'fs/sysfs/inode.c')
| -rw-r--r-- | fs/sysfs/inode.c | 135 |
1 files changed, 99 insertions, 36 deletions
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c index 555f0ff..e28cecf 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -18,6 +18,8 @@ #include <linux/capability.h> #include <linux/errno.h> #include <linux/sched.h> +#include <linux/xattr.h> +#include <linux/security.h> #include "sysfs.h" extern struct super_block * sysfs_sb; @@ -29,12 +31,14 @@ static const struct address_space_operations sysfs_aops = { }; static struct backing_dev_info sysfs_backing_dev_info = { + .name = "sysfs", .ra_pages = 0, /* No readahead */ .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, }; static const struct inode_operations sysfs_inode_operations ={ .setattr = sysfs_setattr, + .setxattr = sysfs_setxattr, }; int __init sysfs_inode_init(void) @@ -42,18 +46,37 @@ int __init sysfs_inode_init(void) return bdi_init(&sysfs_backing_dev_info); } +struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd) +{ + struct sysfs_inode_attrs *attrs; + struct iattr *iattrs; + + attrs = kzalloc(sizeof(struct sysfs_inode_attrs), GFP_KERNEL); + if (!attrs) + return NULL; + iattrs = &attrs->ia_iattr; + + /* assign default attributes */ + iattrs->ia_mode = sd->s_mode; + iattrs->ia_uid = 0; + iattrs->ia_gid = 0; + iattrs->ia_atime = iattrs->ia_mtime = iattrs->ia_ctime = CURRENT_TIME; + + return attrs; +} int sysfs_setattr(struct dentry * dentry, struct iattr * iattr) { struct inode * inode = dentry->d_inode; struct sysfs_dirent * sd = dentry->d_fsdata; - struct iattr * sd_iattr; + struct sysfs_inode_attrs *sd_attrs; + struct iattr *iattrs; unsigned int ia_valid = iattr->ia_valid; int error; if (!sd) return -EINVAL; - sd_iattr = sd->s_iattr; + sd_attrs = sd->s_iattr; error = inode_change_ok(inode, iattr); if (error) @@ -65,42 +88,77 @@ int sysfs_setattr(struct dentry * dentry, struct iattr * iattr) if (error) return error; - if (!sd_iattr) { + if (!sd_attrs) { /* setting attributes for the first time, allocate now */ - sd_iattr = kzalloc(sizeof(struct iattr), GFP_KERNEL); - if (!sd_iattr) + sd_attrs = sysfs_init_inode_attrs(sd); + if (!sd_attrs) return -ENOMEM; - /* assign default attributes */ - sd_iattr->ia_mode = sd->s_mode; - sd_iattr->ia_uid = 0; - sd_iattr->ia_gid = 0; - sd_iattr->ia_atime = sd_iattr->ia_mtime = sd_iattr->ia_ctime = CURRENT_TIME; - sd->s_iattr = sd_iattr; + sd->s_iattr = sd_attrs; + } else { + /* attributes were changed at least once in past */ + iattrs = &sd_attrs->ia_iattr; + + if (ia_valid & ATTR_UID) + iattrs->ia_uid = iattr->ia_uid; + if (ia_valid & ATTR_GID) + iattrs->ia_gid = iattr->ia_gid; + if (ia_valid & ATTR_ATIME) + iattrs->ia_atime = timespec_trunc(iattr->ia_atime, + inode->i_sb->s_time_gran); + if (ia_valid & ATTR_MTIME) + iattrs->ia_mtime = timespec_trunc(iattr->ia_mtime, + inode->i_sb->s_time_gran); + if (ia_valid & ATTR_CTIME) + iattrs->ia_ctime = timespec_trunc(iattr->ia_ctime, + inode->i_sb->s_time_gran); + if (ia_valid & ATTR_MODE) { + umode_t mode = iattr->ia_mode; + + if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID)) + mode &= ~S_ISGID; + iattrs->ia_mode = sd->s_mode = mode; + } } + return error; +} - /* attributes were changed atleast once in past */ - - if (ia_valid & ATTR_UID) - sd_iattr->ia_uid = iattr->ia_uid; - if (ia_valid & ATTR_GID) - sd_iattr->ia_gid = iattr->ia_gid; - if (ia_valid & ATTR_ATIME) - sd_iattr->ia_atime = timespec_trunc(iattr->ia_atime, - inode->i_sb->s_time_gran); - if (ia_valid & ATTR_MTIME) - sd_iattr->ia_mtime = timespec_trunc(iattr->ia_mtime, - inode->i_sb->s_time_gran); - if (ia_valid & ATTR_CTIME) - sd_iattr->ia_ctime = timespec_trunc(iattr->ia_ctime, - inode->i_sb->s_time_gran); - if (ia_valid & ATTR_MODE) { - umode_t mode = iattr->ia_mode; - - if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID)) - mode &= ~S_ISGID; - sd_iattr->ia_mode = sd->s_mode = mode; - } +int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, + size_t size, int flags) +{ + struct sysfs_dirent *sd = dentry->d_fsdata; + struct sysfs_inode_attrs *iattrs; + void *secdata; + int error; + u32 secdata_len = 0; + + if (!sd) + return -EINVAL; + if (!sd->s_iattr) + sd->s_iattr = sysfs_init_inode_attrs(sd); + if (!sd->s_iattr) + return -ENOMEM; + + iattrs = sd->s_iattr; + + if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) { + const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; + error = security_inode_setsecurity(dentry->d_inode, suffix, + value, size, flags); + if (error) + goto out; + error = security_inode_getsecctx(dentry->d_inode, + &secdata, &secdata_len); + if (error) + goto out; + if (iattrs->ia_secdata) + security_release_secctx(iattrs->ia_secdata, + iattrs->ia_secdata_len); + iattrs->ia_secdata = secdata; + iattrs->ia_secdata_len = secdata_len; + } else + return -EINVAL; +out: return error; } @@ -146,6 +204,7 @@ static int sysfs_count_nlink(struct sysfs_dirent *sd) static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) { struct bin_attribute *bin_attr; + struct sysfs_inode_attrs *iattrs; inode->i_private = sysfs_get(sd); inode->i_mapping->a_ops = &sysfs_aops; @@ -154,16 +213,20 @@ static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) inode->i_ino = sd->s_ino; lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key); - if (sd->s_iattr) { + iattrs = sd->s_iattr; + if (iattrs) { /* sysfs_dirent has non-default attributes * get them for the new inode from persistent copy * in sysfs_dirent */ - set_inode_attr(inode, sd->s_iattr); + set_inode_attr(inode, &iattrs->ia_iattr); + if (iattrs->ia_secdata) + security_inode_notifysecctx(inode, + iattrs->ia_secdata, + iattrs->ia_secdata_len); } else set_default_inode_attr(inode, sd->s_mode); - /* initialize inode according to type */ switch (sysfs_type(sd)) { case SYSFS_DIR: |