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: firefly_0821_release~176^2~4^2~40^2~12
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ed30e07de077354993122c5d88e535cbe0a03754;p=firefly-linux-kernel-4.4.55.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 24a9dfb51df2..e3e2dd4c55bf 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -567,6 +567,9 @@ 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;