From: Florian Westphal <fw@strlen.de>
Date: Fri, 1 Apr 2016 12:17:25 +0000 (+0200)
Subject: netfilter: x_tables: assert minimum target size
X-Git-Tag: v4.6.3~14
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3902b6dcc704a07dbf79df7ba3cab990b808b6de;p=thirdparty%2Fkernel%2Fstable.git

netfilter: x_tables: assert minimum target size

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>
---

diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 1f44bfa8dd940..ec1b7183fff96 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -568,6 +568,9 @@ int xt_check_entry_offsets(const void *base,
 		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;