diff options
| author | Florian Westphal <fw@strlen.de> | 2016-04-01 14:17:28 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2016-04-14 00:30:37 +0200 |
| commit | ce683e5f9d045e5d67d1312a42b359cb2ab2a13c (patch) | |
| tree | 74c29eb462a8829b7cffac63a09d2e702788144c /net/ipv4 | |
| parent | 7ed2abddd20cf8f6bd27f65bd218f26fa5bf7f44 (diff) | |
netfilter: x_tables: check for bogus target offset
We're currently asserting that targetoff + targetsize <= nextoff.
Extend it to also check that targetoff is >= sizeof(xt_entry).
Since this is generic code, add an argument pointing to the start of the
match/target, we can then derive the base structure size from the delta.
We also need the e->elems pointer in a followup change to validate matches.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/netfilter/arp_tables.c | 5 | ||||
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 5 |
2 files changed, 6 insertions, 4 deletions
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index ab8952a49bfa..95ed4e454c60 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -592,7 +592,8 @@ static inline int check_entry_size_and_hooks(struct arpt_entry *e, if (!arp_checkentry(&e->arp)) return -EINVAL; - err = xt_check_entry_offsets(e, e->target_offset, e->next_offset); + err = xt_check_entry_offsets(e, e->elems, e->target_offset, + e->next_offset); if (err) return err; @@ -1254,7 +1255,7 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, if (!arp_checkentry(&e->arp)) return -EINVAL; - ret = xt_compat_check_entry_offsets(e, e->target_offset, + ret = xt_compat_check_entry_offsets(e, e->elems, e->target_offset, e->next_offset); if (ret) return ret; diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 7d24c872723f..baab033d74e0 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -754,7 +754,8 @@ check_entry_size_and_hooks(struct ipt_entry *e, if (!ip_checkentry(&e->ip)) return -EINVAL; - err = xt_check_entry_offsets(e, e->target_offset, e->next_offset); + err = xt_check_entry_offsets(e, e->elems, e->target_offset, + e->next_offset); if (err) return err; @@ -1513,7 +1514,7 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, if (!ip_checkentry(&e->ip)) return -EINVAL; - ret = xt_compat_check_entry_offsets(e, + ret = xt_compat_check_entry_offsets(e, e->elems, e->target_offset, e->next_offset); if (ret) return ret; |