From: Sebastian Pöhn Date: Mon, 20 Apr 2015 07:19:20 +0000 (+0200) Subject: ip_forward: Drop frames with attached skb->sk X-Git-Tag: v4.1-rc1~55^2~7 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2ab957492d13b;p=karo-tx-linux.git ip_forward: Drop frames with attached skb->sk Initial discussion was: [FYI] xfrm: Don't lookup sk_policy for timewait sockets Forwarded frames should not have a socket attached. Especially tw sockets will lead to panics later-on in the stack. This was observed with TPROXY assigning a tw socket and broken policy routing (misconfigured). As a result frame enters forwarding path instead of input. We cannot solve this in TPROXY as it cannot know that policy routing is broken. v2: Remove useless comment Signed-off-by: Sebastian Poehn Signed-off-by: David S. Miller --- diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c index 939992c456f3..3674484946a5 100644 --- a/net/ipv4/ip_forward.c +++ b/net/ipv4/ip_forward.c @@ -82,6 +82,9 @@ int ip_forward(struct sk_buff *skb) if (skb->pkt_type != PACKET_HOST) goto drop; + if (unlikely(skb->sk)) + goto drop; + if (skb_warn_if_lro(skb)) goto drop;