diff options
| author | Florian Westphal <fw@strlen.de> | 2016-03-22 18:02:49 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2016-03-28 17:59:04 +0200 |
| commit | bdf533de6968e9686df777dc178486f600c6e617 (patch) | |
| tree | 23e87768a52a4d72522765b652cfe8af9bc67e46 /net/ipv4/netfilter/ip_tables.c | |
| parent | 99b7248e2ad57ca93ada10c6598affb267ffc99a (diff) | |
| download | linux-bdf533de6968e9686df777dc178486f600c6e617.tar.gz | |
netfilter: x_tables: validate e->target_offset early
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>
Diffstat (limited to 'net/ipv4/netfilter/ip_tables.c')
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 17 |
1 files changed, 8 insertions, 9 deletions
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index e53f8d6f326d8..1d72a3c4a7e75 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -569,14 +569,12 @@ static void cleanup_match(struct xt_entry_match *m, struct net *net) } static int -check_entry(const struct ipt_entry *e, const char *name) +check_entry(const struct ipt_entry *e) { const struct xt_entry_target *t; - if (!ip_checkentry(&e->ip)) { - duprintf("ip check failed %p %s.\n", e, name); + if (!ip_checkentry(&e->ip)) return -EINVAL; - } if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset) @@ -666,10 +664,6 @@ find_check_entry(struct ipt_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; @@ -741,6 +735,7 @@ check_entry_size_and_hooks(struct ipt_entry *e, unsigned int valid_hooks) { unsigned int h; + int err; if ((unsigned long)e % __alignof__(struct ipt_entry) != 0 || (unsigned char *)e + sizeof(struct ipt_entry) >= limit) { @@ -755,6 +750,10 @@ check_entry_size_and_hooks(struct ipt_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))) @@ -1506,7 +1505,7 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, } /* For purposes of check_entry casting the compat entry is fine */ - ret = check_entry((struct ipt_entry *)e, name); + ret = check_entry((struct ipt_entry *)e); if (ret) return ret; |