xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

netfilter: x_tables: validate e->target_offset early

Browse Source 
We should check that e->target_offset is sane before
mark_source_chains gets called since it will fetch the target entry
for loop detection.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal
2016-03-22 18:02:49 +01:00
committed by Pablo Neira Ayuso
parent 99b7248e2a
commit bdf533de69
3 changed files with 24 additions and 27 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
net/ipv6/netfilter/ip6_tables.c
View File

@@ -581,14 +581,12 @@ static void cleanup_match(struct xt_entry_match *m, struct net *net)
}
static int
check_entry(const struct ip6t_entry *e, const char *name)
check_entry(const struct ip6t_entry *e)
{
const struct xt_entry_target *t;
if (!ip6_checkentry(&e->ipv6)) {
duprintf("ip_tables: ip check failed %p %s.\n", e, name);
if (!ip6_checkentry(&e->ipv6))
return -EINVAL;
}
if (e->target_offset + sizeof(struct xt_entry_target) >
e->next_offset)
@@ -679,10 +677,6 @@ find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
struct xt_mtchk_param mtpar;
struct xt_entry_match *ematch;
ret = check_entry(e, name);
if (ret)
return ret;
e->counters.pcnt = xt_percpu_counter_alloc();
if (IS_ERR_VALUE(e->counters.pcnt))
return -ENOMEM;
@@ -753,6 +747,7 @@ check_entry_size_and_hooks(struct ip6t_entry *e,
unsigned int valid_hooks)
{
unsigned int h;
int err;
if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 ||
(unsigned char *)e + sizeof(struct ip6t_entry) >= limit) {
@@ -767,6 +762,10 @@ check_entry_size_and_hooks(struct ip6t_entry *e,
return -EINVAL;
}
err = check_entry(e);
if (err)
return err;
/* Check hooks & underflows */
for (h = 0; h < NF_INET_NUMHOOKS; h++) {
if (!(valid_hooks & (1 << h)))
@@ -1518,7 +1517,7 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
}
/* For purposes of check_entry casting the compat entry is fine */
ret = check_entry((struct ip6t_entry *)e, name);
ret = check_entry((struct ip6t_entry *)e);
if (ret)
return ret;