From: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Date: Thu, 28 Jun 2012 02:57:47 +0000 (+0000)
Subject: netfilter: nfnetlink: check callbacks before using those in nfnetlink_rcv_msg
X-Git-Tag: v3.6-rc1~125^2~281^2~1
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=59560a38a379b6c9048620ee10711d3c0c5974b3;p=linux-block.git

netfilter: nfnetlink: check callbacks before using those in nfnetlink_rcv_msg

nfnetlink_rcv_msg() might call a NULL callback which will cause NULL pointer
dereference.

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index 3e797d1fcb94..4acdd76bb6c4 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -184,9 +184,11 @@ replay:
 					lockdep_is_held(&nfnl_mutex)) != ss ||
 			    nfnetlink_find_client(type, ss) != nc)
 				err = -EAGAIN;
-			else
+			else if (nc->call)
 				err = nc->call(net->nfnl, skb, nlh,
 						   (const struct nlattr **)cda);
+			else
+				err = -EINVAL;
 			nfnl_unlock();
 		}
 		if (err == -EAGAIN)