[PATCH 3.14 24/29] netfilter: x_tables: assert minimum target size

Greg Kroah-Hartman
2016-06-22T22:40:44Z

From: Florian Westphal <fw@strlen.de>

commit a08e4e190b866579896c09af59b3bdca821da2cd upstream.

The target size includes the size of the xt_entry_target struct.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
net/netfilter/x_tables.c | 3 +++
1 file changed, 3 insertions(+)

--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -587,6 +587,9 @@ int xt_check_entry_offsets(const void *b
return -EINVAL;

t = (void *)(e + target_offset);
+ if (t->u.target_size < sizeof(*t))
+ return -EINVAL;
+
if (target_offset + t->u.target_size > next_offset)
return -EINVAL;