From: Ralf Baechle <ralf@linux-mips.org>
Date: Thu, 18 Jun 2015 22:46:53 +0000 (+0200)
Subject: NET: ROSE: Don't dereference NULL neighbour pointer.
X-Git-Tag: v3.4.109~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bee5f3e274eef419680b1349540a9d8032c99289;p=thirdparty%2Fkernel%2Fstable.git

NET: ROSE: Don't dereference NULL neighbour pointer.

commit d496f7842aada20c61e6044b3395383fa972872c upstream.

A ROSE socket doesn't necessarily always have a neighbour pointer so check
if the neighbour pointer is valid before dereferencing it.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Tested-by: Bernard Pidoux <f6bvp@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Zefan Li <lizefan@huawei.com>
---

diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
index bde7d69b440da..e895636550303 100644
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -194,7 +194,8 @@ static void rose_kill_by_device(struct net_device *dev)
 
 		if (rose->device == dev) {
 			rose_disconnect(s, ENETUNREACH, ROSE_OUT_OF_ORDER, 0);
-			rose->neighbour->use--;
+			if (rose->neighbour)
+				rose->neighbour->use--;
 			rose->device = NULL;
 		}
 	}