netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH net] l2tp: avoid use-after-free caused by l2tp_ip_backlog_recv
@ 2017-02-26 16:58 Paul Hüber
  2017-02-27  3:58 ` David Miller
  0 siblings, 1 reply; 2+ messages in thread
From: Paul Hüber @ 2017-02-26 16:58 UTC (permalink / raw)
  To: netdev

l2tp_ip_backlog_recv may not return -1 if the packet gets dropped.
The return value is passed up to ip_local_deliver_finish, which treats
negative values as an IP protocol number for resubmission.

Signed-off-by: Paul Hüber <phueber@kernsp.in>
---
 net/l2tp/l2tp_ip.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/l2tp/l2tp_ip.c b/net/l2tp/l2tp_ip.c
index 28c21546d5b6..3ed30153a6f5 100644
--- a/net/l2tp/l2tp_ip.c
+++ b/net/l2tp/l2tp_ip.c
@@ -381,7 +381,7 @@ static int l2tp_ip_backlog_recv(struct sock *sk, struct sk_buff *skb)
 drop:
 	IP_INC_STATS(sock_net(sk), IPSTATS_MIB_INDISCARDS);
 	kfree_skb(skb);
-	return -1;
+	return 0;
 }
 
 /* Userspace will call sendmsg() on the tunnel socket to send L2TP
-- 
2.11.1

^ permalink raw reply related	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2017-02-27  4:53 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-02-26 16:58 [PATCH net] l2tp: avoid use-after-free caused by l2tp_ip_backlog_recv Paul Hüber
2017-02-27  3:58 ` David Miller

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).