ip_forward: Drop frames with attached skb->sk

[ Upstream commit 2ab957492d13bb819400ac29ae55911d50a82a13 ]

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 <sebastian.poehn@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This commit is contained in:

Sebastian Pöhn

2015-04-20 09:19:20 +02:00

committed by

Greg Kroah-Hartman

parent 89bf6007dd

commit fb138c4699

1 changed files with 3 additions and 0 deletions

									
										net/ipv4/ip_forward.c
									
		+3
		
												View File
												
				@@ -126,6 +126,9 @@ int ip_forward(struct sk_buff *skb)

					struct rtable *rt;	/* Route we use */

					struct ip_options *opt	= &(IPCB(skb)->opt);

					if (unlikely(skb->sk))

						goto drop;

					if (skb_warn_if_lro(skb))

						goto drop;