| From foo@baz Wed Apr 29 11:59:49 CEST 2015 |
| From: =?UTF-8?q?Sebastian=20P=C3=B6hn?= <sebastian.poehn@gmail.com> |
| Date: Mon, 20 Apr 2015 09:19:20 +0200 |
| Subject: ip_forward: Drop frames with attached skb->sk |
| |
| From: =?UTF-8?q?Sebastian=20P=C3=B6hn?= <sebastian.poehn@gmail.com> |
| |
| [ 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> |
| --- |
| net/ipv4/ip_forward.c | 3 +++ |
| 1 file changed, 3 insertions(+) |
| |
| --- 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; |
| |
