UPSTREAM: netfilter: x_tables: make sure e->next_offset covers remaining blob size

(cherry pick from commit 6e94e0cfb0)

Otherwise this function may read data beyond the ruleset blob.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I9d19ecf3e00a2d52817b35b9042623927895c005
Bug: 29637687
This commit is contained in:
Florian Westphal
2016-03-22 18:02:50 +01:00
committed by Min Chong
parent 44bd40ae32
commit 160202a2e8
3 changed files with 12 additions and 6 deletions

View File

@@ -573,7 +573,8 @@ static inline int check_entry_size_and_hooks(struct arpt_entry *e,
int err;
if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 ||
(unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
(unsigned char *)e + sizeof(struct arpt_entry) >= limit ||
(unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p\n", e);
return -EINVAL;
}
@@ -1232,7 +1233,8 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
(unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) {
(unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit ||
(unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p, limit = %p\n", e, limit);
return -EINVAL;
}

View File

@@ -737,7 +737,8 @@ check_entry_size_and_hooks(struct ipt_entry *e,
int err;
if ((unsigned long)e % __alignof__(struct ipt_entry) != 0 ||
(unsigned char *)e + sizeof(struct ipt_entry) >= limit) {
(unsigned char *)e + sizeof(struct ipt_entry) >= limit ||
(unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p\n", e);
return -EINVAL;
}
@@ -1491,7 +1492,8 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 ||
(unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit) {
(unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit ||
(unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p, limit = %p\n", e, limit);
return -EINVAL;
}

View File

@@ -749,7 +749,8 @@ check_entry_size_and_hooks(struct ip6t_entry *e,
int err;
if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 ||
(unsigned char *)e + sizeof(struct ip6t_entry) >= limit) {
(unsigned char *)e + sizeof(struct ip6t_entry) >= limit ||
(unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p\n", e);
return -EINVAL;
}
@@ -1503,7 +1504,8 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
duprintf("check_compat_entry_size_and_hooks %p\n", e);
if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 ||
(unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit) {
(unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit ||
(unsigned char *)e + e->next_offset > limit) {
duprintf("Bad offset %p, limit = %p\n", e, limit);
return -EINVAL;
}