From: Ido Schimmel <idosch@mellanox.com>
Date: Fri, 1 Mar 2019 13:38:43 +0000 (+0000)
Subject: net: ipv4: Fix NULL pointer dereference in route lookup
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=2a8e4997dbb2818061c76ee57d7becf390c0e4bc;p=openwrt%2Fstaging%2Fblogic.git

net: ipv4: Fix NULL pointer dereference in route lookup

When calculating the multipath hash for input routes the flow info is
not available and therefore should not be used.

Fixes: 24ba14406c5c ("route: Add multipath_hash in flowi_common to make user-define hash")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Cc: wenxu <wenxu@ucloud.cn>
Acked-by: wenxu <wenxu@ucloud.cn>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 7cf4c8305071..e3ac458b5d8b 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1820,7 +1820,7 @@ out:
 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
 		       const struct sk_buff *skb, struct flow_keys *flkeys)
 {
-	u32 multipath_hash = fl4->flowi4_multipath_hash;
+	u32 multipath_hash = fl4 ? fl4->flowi4_multipath_hash : 0;
 	struct flow_keys hash_keys;
 	u32 mhash;