From d109e61bfe7a468fd8df4a7ceb65635e7aa909a0 Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Wed, 30 Nov 2016 02:56:47 +0900 Subject: [PATCH] net: ipv4: Don't crash if passing a null sk to ip_rt_update_pmtu. Commit e2d118a1cb5e ("net: inet: Support UID-based routing in IP protocols.") made __build_flow_key call sock_net(sk) to determine the network namespace of the passed-in socket. This crashes if sk is NULL. Fix this by getting the network namespace from the skb instead. Fixes: e2d118a1cb5e ("net: inet: Support UID-based routing in IP protocols.") Reported-by: Erez Shitrit Signed-off-by: Lorenzo Colitti Signed-off-by: David S. Miller --- net/ipv4/route.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index d37fc6f7e679..6402d745d192 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -531,13 +531,14 @@ static void __build_flow_key(const struct net *net, struct flowi4 *fl4, static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb, const struct sock *sk) { + const struct net *net = dev_net(skb->dev); const struct iphdr *iph = ip_hdr(skb); int oif = skb->dev->ifindex; u8 tos = RT_TOS(iph->tos); u8 prot = iph->protocol; u32 mark = skb->mark; - __build_flow_key(sock_net(sk), fl4, sk, iph, oif, tos, prot, mark, 0); + __build_flow_key(net, fl4, sk, iph, oif, tos, prot, mark, 0); } static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)