diff options
author | David S. Miller <davem@davemloft.net> | 2016-04-24 04:12:08 (GMT) |
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committer | David S. Miller <davem@davemloft.net> | 2016-04-24 04:12:08 (GMT) |
commit | 11afbff86168bc2ce11ae9d64ff687567a2352de (patch) | |
tree | bd52f34a04e09d6c444784569017225af7e5db9f /net/ipv4/netfilter | |
parent | 8d9ea1606f6c3a1046abae5c2c85eb0e02e43db3 (diff) | |
parent | a163f2cb393d9d71cad57bfe6a8c7f452a478fb4 (diff) | |
download | linux-11afbff86168bc2ce11ae9d64ff687567a2352de.tar.xz |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for your net-next
tree, mostly from Florian Westphal to sort out the lack of sufficient
validation in x_tables and connlabel preparation patches to add
nf_tables support. They are:
1) Ensure we don't go over the ruleset blob boundaries in
mark_source_chains().
2) Validate that target jumps land on an existing xt_entry. This extra
sanitization comes with a performance penalty when loading the ruleset.
3) Introduce xt_check_entry_offsets() and use it from {arp,ip,ip6}tables.
4) Get rid of the smallish check_entry() functions in {arp,ip,ip6}tables.
5) Make sure the minimal possible target size in x_tables.
6) Similar to #3, add xt_compat_check_entry_offsets() for compat code.
7) Check that standard target size is valid.
8) More sanitization to ensure that the target_offset field is correct.
9) Add xt_check_entry_match() to validate that matches are well-formed.
10-12) Three patch to reduce the number of parameters in
translate_compat_table() for {arp,ip,ip6}tables by using a container
structure.
13) No need to return value from xt_compat_match_from_user(), so make
it void.
14) Consolidate translate_table() so it can be used by compat code too.
15) Remove obsolete check for compat code, so we keep consistent with
what was already removed in the native layout code (back in 2007).
16) Get rid of target jump validation from mark_source_chains(),
obsoleted by #2.
17) Introduce xt_copy_counters_from_user() to consolidate counter
copying, and use it from {arp,ip,ip6}tables.
18,22) Get rid of unnecessary explicit inlining in ctnetlink for dump
functions.
19) Move nf_connlabel_match() to xt_connlabel.
20) Skip event notification if connlabel did not change.
21) Update of nf_connlabels_get() to make the upcoming nft connlabel
support easier.
23) Remove spinlock to read protocol state field in conntrack.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/netfilter')
-rw-r--r-- | net/ipv4/netfilter/arp_tables.c | 303 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 327 |
2 files changed, 175 insertions, 455 deletions
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 4133b0f..60f5161 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -367,6 +367,18 @@ static inline bool unconditional(const struct arpt_entry *e) memcmp(&e->arp, &uncond, sizeof(uncond)) == 0; } +static bool find_jump_target(const struct xt_table_info *t, + const struct arpt_entry *target) +{ + struct arpt_entry *iter; + + xt_entry_foreach(iter, t->entries, t->size) { + if (iter == target) + return true; + } + return false; +} + /* Figures out from what hook each rule can be called: returns 0 if * there are loops. Puts hook bitmask in comefrom. */ @@ -439,6 +451,8 @@ static int mark_source_chains(const struct xt_table_info *newinfo, size = e->next_offset; e = (struct arpt_entry *) (entry0 + pos + size); + if (pos + size >= newinfo->size) + return 0; e->counters.pcnt = pos; pos += size; } else { @@ -447,20 +461,18 @@ static int mark_source_chains(const struct xt_table_info *newinfo, if (strcmp(t->target.u.user.name, XT_STANDARD_TARGET) == 0 && newpos >= 0) { - if (newpos > newinfo->size - - sizeof(struct arpt_entry)) { - duprintf("mark_source_chains: " - "bad verdict (%i)\n", - newpos); - return 0; - } - /* This a jump; chase it. */ duprintf("Jump rule %u -> %u\n", pos, newpos); + e = (struct arpt_entry *) + (entry0 + newpos); + if (!find_jump_target(newinfo, e)) + return 0; } else { /* ... this is a fallthru */ newpos = pos + e->next_offset; + if (newpos >= newinfo->size) + return 0; } e = (struct arpt_entry *) (entry0 + newpos); @@ -474,23 +486,6 @@ next: return 1; } -static inline int check_entry(const struct arpt_entry *e) -{ - const struct xt_entry_target *t; - - if (!arp_checkentry(&e->arp)) - return -EINVAL; - - if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset) - return -EINVAL; - - t = arpt_get_target_c(e); - if (e->target_offset + t->u.target_size > e->next_offset) - return -EINVAL; - - return 0; -} - static inline int check_target(struct arpt_entry *e, const char *name) { struct xt_entry_target *t = arpt_get_target(e); @@ -586,7 +581,11 @@ static inline int check_entry_size_and_hooks(struct arpt_entry *e, return -EINVAL; } - err = check_entry(e); + if (!arp_checkentry(&e->arp)) + return -EINVAL; + + err = xt_check_entry_offsets(e, e->elems, e->target_offset, + e->next_offset); if (err) return err; @@ -691,10 +690,8 @@ static int translate_table(struct xt_table_info *newinfo, void *entry0, } } - if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) { - duprintf("Looping hook\n"); + if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) return -ELOOP; - } /* Finally, each sanity check must pass */ i = 0; @@ -1126,55 +1123,17 @@ static int do_add_counters(struct net *net, const void __user *user, unsigned int i; struct xt_counters_info tmp; struct xt_counters *paddc; - unsigned int num_counters; - const char *name; - int size; - void *ptmp; struct xt_table *t; const struct xt_table_info *private; int ret = 0; struct arpt_entry *iter; unsigned int addend; -#ifdef CONFIG_COMPAT - struct compat_xt_counters_info compat_tmp; - - if (compat) { - ptmp = &compat_tmp; - size = sizeof(struct compat_xt_counters_info); - } else -#endif - { - ptmp = &tmp; - size = sizeof(struct xt_counters_info); - } - - if (copy_from_user(ptmp, user, size) != 0) - return -EFAULT; - -#ifdef CONFIG_COMPAT - if (compat) { - num_counters = compat_tmp.num_counters; - name = compat_tmp.name; - } else -#endif - { - num_counters = tmp.num_counters; - name = tmp.name; - } - if (len != size + num_counters * sizeof(struct xt_counters)) - return -EINVAL; - - paddc = vmalloc(len - size); - if (!paddc) - return -ENOMEM; + paddc = xt_copy_counters_from_user(user, len, &tmp, compat); + if (IS_ERR(paddc)) + return PTR_ERR(paddc); - if (copy_from_user(paddc, user + size, len - size) != 0) { - ret = -EFAULT; - goto free; - } - - t = xt_find_table_lock(net, NFPROTO_ARP, name); + t = xt_find_table_lock(net, NFPROTO_ARP, tmp.name); if (IS_ERR_OR_NULL(t)) { ret = t ? PTR_ERR(t) : -ENOENT; goto free; @@ -1182,7 +1141,7 @@ static int do_add_counters(struct net *net, const void __user *user, local_bh_disable(); private = t->private; - if (private->number != num_counters) { + if (private->number != tmp.num_counters) { ret = -EINVAL; goto unlock_up_free; } @@ -1209,6 +1168,18 @@ static int do_add_counters(struct net *net, const void __user *user, } #ifdef CONFIG_COMPAT +struct compat_arpt_replace { + char name[XT_TABLE_MAXNAMELEN]; + u32 valid_hooks; + u32 num_entries; + u32 size; + u32 hook_entry[NF_ARP_NUMHOOKS]; + u32 underflow[NF_ARP_NUMHOOKS]; + u32 num_counters; + compat_uptr_t counters; + struct compat_arpt_entry entries[0]; +}; + static inline void compat_release_entry(struct compat_arpt_entry *e) { struct xt_entry_target *t; @@ -1217,20 +1188,17 @@ static inline void compat_release_entry(struct compat_arpt_entry *e) module_put(t->u.kernel.target->me); } -static inline int +static int check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, struct xt_table_info *newinfo, unsigned int *size, const unsigned char *base, - const unsigned char *limit, - const unsigned int *hook_entries, - const unsigned int *underflows, - const char *name) + const unsigned char *limit) { struct xt_entry_target *t; struct xt_target *target; unsigned int entry_offset; - int ret, off, h; + int ret, off; duprintf("check_compat_entry_size_and_hooks %p\n", e); if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 || @@ -1247,8 +1215,11 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, return -EINVAL; } - /* For purposes of check_entry casting the compat entry is fine */ - ret = check_entry((struct arpt_entry *)e); + if (!arp_checkentry(&e->arp)) + return -EINVAL; + + ret = xt_compat_check_entry_offsets(e, e->elems, e->target_offset, + e->next_offset); if (ret) return ret; @@ -1272,17 +1243,6 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, if (ret) goto release_target; - /* Check hooks & underflows */ - for (h = 0; h < NF_ARP_NUMHOOKS; h++) { - if ((unsigned char *)e - base == hook_entries[h]) - newinfo->hook_entry[h] = hook_entries[h]; - if ((unsigned char *)e - base == underflows[h]) - newinfo->underflow[h] = underflows[h]; - } - - /* Clear counters and comefrom */ - memset(&e->counters, 0, sizeof(e->counters)); - e->comefrom = 0; return 0; release_target: @@ -1291,18 +1251,17 @@ out: return ret; } -static int +static void compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr, - unsigned int *size, const char *name, + unsigned int *size, struct xt_table_info *newinfo, unsigned char *base) { struct xt_entry_target *t; struct xt_target *target; struct arpt_entry *de; unsigned int origsize; - int ret, h; + int h; - ret = 0; origsize = *size; de = (struct arpt_entry *)*dstptr; memcpy(de, e, sizeof(struct arpt_entry)); @@ -1323,148 +1282,82 @@ compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr, if ((unsigned char *)de - base < newinfo->underflow[h]) newinfo->underflow[h] -= origsize - *size; } - return ret; } -static int translate_compat_table(const char *name, - unsigned int valid_hooks, - struct xt_table_info **pinfo, +static int translate_compat_table(struct xt_table_info **pinfo, void **pentry0, - unsigned int total_size, - unsigned int number, - unsigned int *hook_entries, - unsigned int *underflows) + const struct compat_arpt_replace *compatr) { unsigned int i, j; struct xt_table_info *newinfo, *info; void *pos, *entry0, *entry1; struct compat_arpt_entry *iter0; - struct arpt_entry *iter1; + struct arpt_replace repl; unsigned int size; int ret = 0; info = *pinfo; entry0 = *pentry0; - size = total_size; - info->number = number; - - /* Init all hooks to impossible value. */ - for (i = 0; i < NF_ARP_NUMHOOKS; i++) { - info->hook_entry[i] = 0xFFFFFFFF; - info->underflow[i] = 0xFFFFFFFF; - } + size = compatr->size; + info->number = compatr->num_entries; duprintf("translate_compat_table: size %u\n", info->size); j = 0; xt_compat_lock(NFPROTO_ARP); - xt_compat_init_offsets(NFPROTO_ARP, number); + xt_compat_init_offsets(NFPROTO_ARP, compatr->num_entries); /* Walk through entries, checking offsets. */ - xt_entry_foreach(iter0, entry0, total_size) { + xt_entry_foreach(iter0, entry0, compatr->size) { ret = check_compat_entry_size_and_hooks(iter0, info, &size, entry0, - entry0 + total_size, - hook_entries, - underflows, - name); + entry0 + compatr->size); if (ret != 0) goto out_unlock; ++j; } ret = -EINVAL; - if (j != number) { + if (j != compatr->num_entries) { duprintf("translate_compat_table: %u not %u entries\n", - j, number); + j, compatr->num_entries); goto out_unlock; } - /* Check hooks all assigned */ - for (i = 0; i < NF_ARP_NUMHOOKS; i++) { - /* Only hooks which are valid */ - if (!(valid_hooks & (1 << i))) - continue; - if (info->hook_entry[i] == 0xFFFFFFFF) { - duprintf("Invalid hook entry %u %u\n", - i, hook_entries[i]); - goto out_unlock; - } - if (info->underflow[i] == 0xFFFFFFFF) { - duprintf("Invalid underflow %u %u\n", - i, underflows[i]); - goto out_unlock; - } - } - ret = -ENOMEM; newinfo = xt_alloc_table_info(size); if (!newinfo) goto out_unlock; - newinfo->number = number; + newinfo->number = compatr->num_entries; for (i = 0; i < NF_ARP_NUMHOOKS; i++) { newinfo->hook_entry[i] = info->hook_entry[i]; newinfo->underflow[i] = info->underflow[i]; } entry1 = newinfo->entries; pos = entry1; - size = total_size; - xt_entry_foreach(iter0, entry0, total_size) { - ret = compat_copy_entry_from_user(iter0, &pos, &size, - name, newinfo, entry1); - if (ret != 0) - break; - } + size = compatr->size; + xt_entry_foreach(iter0, entry0, compatr->size) + compat_copy_entry_from_user(iter0, &pos, &size, + newinfo, entry1); + + /* all module references in entry0 are now gone */ + xt_compat_flush_offsets(NFPROTO_ARP); xt_compat_unlock(NFPROTO_ARP); - if (ret) - goto free_newinfo; - ret = -ELOOP; - if (!mark_source_chains(newinfo, valid_hooks, entry1)) - goto free_newinfo; + memcpy(&repl, compatr, sizeof(*compatr)); - i = 0; - xt_entry_foreach(iter1, entry1, newinfo->size) { - iter1->counters.pcnt = xt_percpu_counter_alloc(); - if (IS_ERR_VALUE(iter1->counters.pcnt)) { - ret = -ENOMEM; - break; - } - - ret = check_target(iter1, name); - if (ret != 0) { - xt_percpu_counter_free(iter1->counters.pcnt); - break; - } - ++i; - if (strcmp(arpt_get_target(iter1)->u.user.name, - XT_ERROR_TARGET) == 0) - ++newinfo->stacksize; - } - if (ret) { - /* - * The first i matches need cleanup_entry (calls ->destroy) - * because they had called ->check already. The other j-i - * entries need only release. - */ - int skip = i; - j -= i; - xt_entry_foreach(iter0, entry0, newinfo->size) { - if (skip-- > 0) - continue; - if (j-- == 0) - break; - compat_release_entry(iter0); - } - xt_entry_foreach(iter1, entry1, newinfo->size) { - if (i-- == 0) - break; - cleanup_entry(iter1); - } - xt_free_table_info(newinfo); - return ret; + for (i = 0; i < NF_ARP_NUMHOOKS; i++) { + repl.hook_entry[i] = newinfo->hook_entry[i]; + repl.underflow[i] = newinfo->underflow[i]; } + repl.num_counters = 0; + repl.counters = NULL; + repl.size = newinfo->size; + ret = translate_table(newinfo, entry1, &repl); + if (ret) + goto free_newinfo; + *pinfo = newinfo; *pentry0 = entry1; xt_free_table_info(info); @@ -1472,31 +1365,18 @@ static int translate_compat_table(const char *name, free_newinfo: xt_free_table_info(newinfo); -out: - xt_entry_foreach(iter0, entry0, total_size) { + return ret; +out_unlock: + xt_compat_flush_offsets(NFPROTO_ARP); + xt_compat_unlock(NFPROTO_ARP); + xt_entry_foreach(iter0, entry0, compatr->size) { if (j-- == 0) break; compat_release_entry(iter0); } return ret; -out_unlock: - xt_compat_flush_offsets(NFPROTO_ARP); - xt_compat_unlock(NFPROTO_ARP); - goto out; } -struct compat_arpt_replace { - char name[XT_TABLE_MAXNAMELEN]; - u32 valid_hooks; - u32 num_entries; - u32 size; - u32 hook_entry[NF_ARP_NUMHOOKS]; - u32 underflow[NF_ARP_NUMHOOKS]; - u32 num_counters; - compat_uptr_t counters; - struct compat_arpt_entry entries[0]; -}; - static int compat_do_replace(struct net *net, void __user *user, unsigned int len) { @@ -1510,8 +1390,6 @@ static int compat_do_replace(struct net *net, void __user *user, return -EFAULT; /* overflow check */ - if (tmp.size >= INT_MAX / num_possible_cpus()) - return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; if (tmp.num_counters == 0) @@ -1529,10 +1407,7 @@ static int compat_do_replace(struct net *net, void __user *user, goto free_newinfo; } - ret = translate_compat_table(tmp.name, tmp.valid_hooks, - &newinfo, &loc_cpu_entry, tmp.size, - tmp.num_entries, tmp.hook_entry, - tmp.underflow); + ret = translate_compat_table(&newinfo, &loc_cpu_entry, &tmp); if (ret != 0) goto free_newinfo; diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 631c100..735d1ee 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -443,6 +443,18 @@ ipt_do_table(struct sk_buff *skb, #endif } +static bool find_jump_target(const struct xt_table_info *t, + const struct ipt_entry *target) +{ + struct ipt_entry *iter; + + xt_entry_foreach(iter, t->entries, t->size) { + if (iter == target) + return true; + } + return false; +} + /* Figures out from what hook each rule can be called: returns 0 if there are loops. Puts hook bitmask in comefrom. */ static int @@ -520,6 +532,8 @@ mark_source_chains(const struct xt_table_info *newinfo, size = e->next_offset; e = (struct ipt_entry *) (entry0 + pos + size); + if (pos + size >= newinfo->size) + return 0; e->counters.pcnt = pos; pos += size; } else { @@ -528,19 +542,18 @@ mark_source_chains(const struct xt_table_info *newinfo, if (strcmp(t->target.u.user.name, XT_STANDARD_TARGET) == 0 && newpos >= 0) { - if (newpos > newinfo->size - - sizeof(struct ipt_entry)) { - duprintf("mark_source_chains: " - "bad verdict (%i)\n", - newpos); - return 0; - } /* This a jump; chase it. */ duprintf("Jump rule %u -> %u\n", pos, newpos); + e = (struct ipt_entry *) + (entry0 + newpos); + if (!find_jump_target(newinfo, e)) + return 0; } else { /* ... this is a fallthru */ newpos = pos + e->next_offset; + if (newpos >= newinfo->size) + return 0; } e = (struct ipt_entry *) (entry0 + newpos); @@ -568,25 +581,6 @@ static void cleanup_match(struct xt_entry_match *m, struct net *net) } static int -check_entry(const struct ipt_entry *e) -{ - const struct xt_entry_target *t; - - if (!ip_checkentry(&e->ip)) - return -EINVAL; - - if (e->target_offset + sizeof(struct xt_entry_target) > - e->next_offset) - return -EINVAL; - - t = ipt_get_target_c(e); - if (e->target_offset + t->u.target_size > e->next_offset) - return -EINVAL; - - return 0; -} - -static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par) { const struct ipt_ip *ip = par->entryinfo; @@ -750,7 +744,11 @@ check_entry_size_and_hooks(struct ipt_entry *e, return -EINVAL; } - err = check_entry(e); + if (!ip_checkentry(&e->ip)) + return -EINVAL; + + err = xt_check_entry_offsets(e, e->elems, e->target_offset, + e->next_offset); if (err) return err; @@ -1309,55 +1307,17 @@ do_add_counters(struct net *net, const void __user *user, unsigned int i; struct xt_counters_info tmp; struct xt_counters *paddc; - unsigned int num_counters; - const char *name; - int size; - void *ptmp; struct xt_table *t; const struct xt_table_info *private; int ret = 0; struct ipt_entry *iter; unsigned int addend; -#ifdef CONFIG_COMPAT - struct compat_xt_counters_info compat_tmp; - - if (compat) { - ptmp = &compat_tmp; - size = sizeof(struct compat_xt_counters_info); - } else -#endif - { - ptmp = &tmp; - size = sizeof(struct xt_counters_info); - } - - if (copy_from_user(ptmp, user, size) != 0) - return -EFAULT; - -#ifdef CONFIG_COMPAT - if (compat) { - num_counters = compat_tmp.num_counters; - name = compat_tmp.name; - } else -#endif - { - num_counters = tmp.num_counters; - name = tmp.name; - } - - if (len != size + num_counters * sizeof(struct xt_counters)) - return -EINVAL; - paddc = vmalloc(len - size); - if (!paddc) - return -ENOMEM; + paddc = xt_copy_counters_from_user(user, len, &tmp, compat); + if (IS_ERR(paddc)) + return PTR_ERR(paddc); - if (copy_from_user(paddc, user + size, len - size) != 0) { - ret = -EFAULT; - goto free; - } - - t = xt_find_table_lock(net, AF_INET, name); + t = xt_find_table_lock(net, AF_INET, tmp.name); if (IS_ERR_OR_NULL(t)) { ret = t ? PTR_ERR(t) : -ENOENT; goto free; @@ -1365,7 +1325,7 @@ do_add_counters(struct net *net, const void __user *user, local_bh_disable(); private = t->private; - if (private->number != num_counters) { + if (private->number != tmp.num_counters) { ret = -EINVAL; goto unlock_up_free; } @@ -1444,7 +1404,6 @@ compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr, static int compat_find_calc_match(struct xt_entry_match *m, - const char *name, const struct ipt_ip *ip, int *size) { @@ -1479,17 +1438,14 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, struct xt_table_info *newinfo, unsigned int *size, const unsigned char *base, - const unsigned char *limit, - const unsigned int *hook_entries, - const unsigned int *underflows, - const char *name) + const unsigned char *limit) { struct xt_entry_match *ematch; struct xt_entry_target *t; struct xt_target *target; unsigned int entry_offset; unsigned int j; - int ret, off, h; + int ret, off; duprintf("check_compat_entry_size_and_hooks %p\n", e); if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 || @@ -1506,8 +1462,11 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, return -EINVAL; } - /* For purposes of check_entry casting the compat entry is fine */ - ret = check_entry((struct ipt_entry *)e); + if (!ip_checkentry(&e->ip)) + return -EINVAL; + + ret = xt_compat_check_entry_offsets(e, e->elems, + e->target_offset, e->next_offset); if (ret) return ret; @@ -1515,7 +1474,7 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, entry_offset = (void *)e - (void *)base; j = 0; xt_ematch_foreach(ematch, e) { - ret = compat_find_calc_match(ematch, name, &e->ip, &off); + ret = compat_find_calc_match(ematch, &e->ip, &off); if (ret != 0) goto release_matches; ++j; @@ -1538,17 +1497,6 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, if (ret) goto out; - /* Check hooks & underflows */ - for (h = 0; h < NF_INET_NUMHOOKS; h++) { - if ((unsigned char *)e - base == hook_entries[h]) - newinfo->hook_entry[h] = hook_entries[h]; - if ((unsigned char *)e - base == underflows[h]) - newinfo->underflow[h] = underflows[h]; - } - - /* Clear counters and comefrom */ - memset(&e->counters, 0, sizeof(e->counters)); - e->comefrom = 0; return 0; out: @@ -1562,19 +1510,18 @@ release_matches: return ret; } -static int +static void compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr, - unsigned int *size, const char *name, + unsigned int *size, struct xt_table_info *newinfo, unsigned char *base) { struct xt_entry_target *t; struct xt_target *target; struct ipt_entry *de; unsigned int origsize; - int ret, h; + int h; struct xt_entry_match *ematch; - ret = 0; origsize = *size; de = (struct ipt_entry *)*dstptr; memcpy(de, e, sizeof(struct ipt_entry)); @@ -1583,201 +1530,105 @@ compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr, *dstptr += sizeof(struct ipt_entry); *size += sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry); - xt_ematch_foreach(ematch, e) { - ret = xt_compat_match_from_user(ematch, dstptr, size); - if (ret != 0) - return ret; - } + xt_ematch_foreach(ematch, e) + xt_compat_match_from_user(ematch, dstptr, size); + de->target_offset = e->target_offset - (origsize - *size); t = compat_ipt_get_target(e); target = t->u.kernel.target; xt_compat_target_from_user(t, dstptr, size); de->next_offset = e->next_offset - (origsize - *size); + for (h = 0; h < NF_INET_NUMHOOKS; h++) { if ((unsigned char *)de - base < newinfo->hook_entry[h]) newinfo->hook_entry[h] -= origsize - *size; if ((unsigned char *)de - base < newinfo->underflow[h]) newinfo->underflow[h] -= origsize - *size; } - return ret; -} - -static int -compat_check_entry(struct ipt_entry *e, struct net *net, const char *name) -{ - struct xt_entry_match *ematch; - struct xt_mtchk_param mtpar; - unsigned int j; - int ret = 0; - - e->counters.pcnt = xt_percpu_counter_alloc(); - if (IS_ERR_VALUE(e->counters.pcnt)) - return -ENOMEM; - - j = 0; - mtpar.net = net; - mtpar.table = name; - mtpar.entryinfo = &e->ip; - mtpar.hook_mask = e->comefrom; - mtpar.family = NFPROTO_IPV4; - xt_ematch_foreach(ematch, e) { - ret = check_match(ematch, &mtpar); - if (ret != 0) - goto cleanup_matches; - ++j; - } - - ret = check_target(e, net, name); - if (ret) - goto cleanup_matches; - return 0; - - cleanup_matches: - xt_ematch_foreach(ematch, e) { - if (j-- == 0) - break; - cleanup_match(ematch, net); - } - - xt_percpu_counter_free(e->counters.pcnt); - - return ret; } static int translate_compat_table(struct net *net, - const char *name, - unsigned int valid_hooks, struct xt_table_info **pinfo, void **pentry0, - unsigned int total_size, - unsigned int number, - unsigned int *hook_entries, - unsigned int *underflows) + const struct compat_ipt_replace *compatr) { unsigned int i, j; struct xt_table_info *newinfo, *info; void *pos, *entry0, *entry1; struct compat_ipt_entry *iter0; - struct ipt_entry *iter1; + struct ipt_replace repl; unsigned int size; int ret; info = *pinfo; entry0 = *pentry0; - size = total_size; - info->number = number; - - /* Init all hooks to impossible value. */ - for (i = 0; i < NF_INET_NUMHOOKS; i++) { - info->hook_entry[i] = 0xFFFFFFFF; - info->underflow[i] = 0xFFFFFFFF; - } + size = compatr->size; + info->number = compatr->num_entries; duprintf("translate_compat_table: size %u\n", info->size); j = 0; xt_compat_lock(AF_INET); - xt_compat_init_offsets(AF_INET, number); + xt_compat_init_offsets(AF_INET, compatr->num_entries); /* Walk through entries, checking offsets. */ - xt_entry_foreach(iter0, entry0, total_size) { + xt_entry_foreach(iter0, entry0, compatr->size) { ret = check_compat_entry_size_and_hooks(iter0, info, &size, entry0, - entry0 + total_size, - hook_entries, - underflows, - name); + entry0 + compatr->size); if (ret != 0) goto out_unlock; ++j; } ret = -EINVAL; - if (j != number) { + if (j != compatr->num_entries) { duprintf("translate_compat_table: %u not %u entries\n", - j, number); + j, compatr->num_entries); goto out_unlock; } - /* Check hooks all assigned */ - for (i = 0; i < NF_INET_NUMHOOKS; i++) { - /* Only hooks which are valid */ - if (!(valid_hooks & (1 << i))) - continue; - if (info->hook_entry[i] == 0xFFFFFFFF) { - duprintf("Invalid hook entry %u %u\n", - i, hook_entries[i]); - goto out_unlock; - } - if (info->underflow[i] == 0xFFFFFFFF) { - duprintf("Invalid underflow %u %u\n", - i, underflows[i]); - goto out_unlock; - } - } - ret = -ENOMEM; newinfo = xt_alloc_table_info(size); if (!newinfo) goto out_unlock; - newinfo->number = number; + newinfo->number = compatr->num_entries; for (i = 0; i < NF_INET_NUMHOOKS; i++) { - newinfo->hook_entry[i] = info->hook_entry[i]; - newinfo->underflow[i] = info->underflow[i]; + newinfo->hook_entry[i] = compatr->hook_entry[i]; + newinfo->underflow[i] = compatr->underflow[i]; } entry1 = newinfo->entries; pos = entry1; - size = total_size; - xt_entry_foreach(iter0, entry0, total_size) { - ret = compat_copy_entry_from_user(iter0, &pos, &size, - name, newinfo, entry1); - if (ret != 0) - break; - } + size = compatr->size; + xt_entry_foreach(iter0, entry0, compatr->size) + compat_copy_entry_from_user(iter0, &pos, &size, + newinfo, entry1); + + /* all module references in entry0 are now gone. + * entry1/newinfo contains a 64bit ruleset that looks exactly as + * generated by 64bit userspace. + * + * Call standard translate_table() to validate all hook_entrys, + * underflows, check for loops, etc. + */ xt_compat_flush_offsets(AF_INET); xt_compat_unlock(AF_INET); - if (ret) - goto free_newinfo; - ret = -ELOOP; - if (!mark_source_chains(newinfo, valid_hooks, entry1)) - goto free_newinfo; + memcpy(&repl, compatr, sizeof(*compatr)); - i = 0; - xt_entry_foreach(iter1, entry1, newinfo->size) { - ret = compat_check_entry(iter1, net, name); - if (ret != 0) - break; - ++i; - if (strcmp(ipt_get_target(iter1)->u.user.name, - XT_ERROR_TARGET) == 0) - ++newinfo->stacksize; - } - if (ret) { - /* - * The first i matches need cleanup_entry (calls ->destroy) - * because they had called ->check already. The other j-i - * entries need only release. - */ - int skip = i; - j -= i; - xt_entry_foreach(iter0, entry0, newinfo->size) { - if (skip-- > 0) - continue; - if (j-- == 0) - break; - compat_release_entry(iter0); - } - xt_entry_foreach(iter1, entry1, newinfo->size) { - if (i-- == 0) - break; - cleanup_entry(iter1, net); - } - xt_free_table_info(newinfo); - return ret; + for (i = 0; i < NF_INET_NUMHOOKS; i++) { + repl.hook_entry[i] = newinfo->hook_entry[i]; + repl.underflow[i] = newinfo->underflow[i]; } + repl.num_counters = 0; + repl.counters = NULL; + repl.size = newinfo->size; + ret = translate_table(net, newinfo, entry1, &repl); + if (ret) + goto free_newinfo; + *pinfo = newinfo; *pentry0 = entry1; xt_free_table_info(info); @@ -1785,17 +1636,16 @@ translate_compat_table(struct net *net, free_newinfo: xt_free_table_info(newinfo); -out: - xt_entry_foreach(iter0, entry0, total_size) { + return ret; +out_unlock: + xt_compat_flush_offsets(AF_INET); + xt_compat_unlock(AF_INET); + xt_entry_foreach(iter0, entry0, compatr->size) { if (j-- == 0) break; compat_release_entry(iter0); } return ret; -out_unlock: - xt_compat_flush_offsets(AF_INET); - xt_compat_unlock(AF_INET); - goto out; } static int @@ -1811,8 +1661,6 @@ compat_do_replace(struct net *net, void __user *user, unsigned int len) return -EFAULT; /* overflow check */ - if (tmp.size >= INT_MAX / num_possible_cpus()) - return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; if (tmp.num_counters == 0) @@ -1831,10 +1679,7 @@ compat_do_replace(struct net *net, void __user *user, unsigned int len) goto free_newinfo; } - ret = translate_compat_table(net, tmp.name, tmp.valid_hooks, - &newinfo, &loc_cpu_entry, tmp.size, - tmp.num_entries, tmp.hook_entry, - tmp.underflow); + ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp); if (ret != 0) goto free_newinfo; |