diff options
| author | Florian Westphal <fw@strlen.de> | 2016-04-01 14:17:28 +0200 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2016-07-10 23:07:34 -0400 |
| commit | 451e4403bc4abc51539376d4314baa739ab9e996 (patch) | |
| tree | 36c2efbe5c91e320847e0992139346eeaa52857b /net/ipv4 | |
| parent | 73bfda1c492bef7038a87adfa887b7e6b7cd6679 (diff) | |
netfilter: x_tables: check for bogus target offset
[ Upstream commit ce683e5f9d045e5d67d1312a42b359cb2ab2a13c ]
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>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
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 d865edf7ae65..53315ee89dcd 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -581,7 +581,8 @@ 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; @@ -1246,7 +1247,7 @@ 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 a355ebbaacf2..fb00670ef2d8 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -741,7 +741,8 @@ 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; @@ -1511,7 +1512,7 @@ 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; |