From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steffen Klassert Subject: [PATCH 2/6] xfrm6: call kfree_skb when skb is toobig Date: Mon, 1 Oct 2018 10:58:51 +0200 Message-ID: <20181001085855.12057-3-steffen.klassert@secunet.com> References: <20181001085855.12057-1-steffen.klassert@secunet.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Herbert Xu , Steffen Klassert , To: David Miller Return-path: Received: from a.mx.secunet.com ([62.96.220.36]:40802 "EHLO a.mx.secunet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728869AbeJAPfq (ORCPT ); Mon, 1 Oct 2018 11:35:46 -0400 In-Reply-To: <20181001085855.12057-1-steffen.klassert@secunet.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Thadeu Lima de Souza Cascardo After commit d6990976af7c5d8f55903bfb4289b6fb030bf754 ("vti6: fix PMTU caching and reporting on xmit"), some too big skbs might be potentially passed down to __xfrm6_output, causing it to fail to transmit but not free the skb, causing a leak of skb, and consequentially a leak of dst references. After running pmtu.sh, that shows as failure to unregister devices in a namespace: [ 311.397671] unregister_netdevice: waiting for veth_b to become free. Usage count = 1 The fix is to call kfree_skb in case of transmit failures. Fixes: dd767856a36e ("xfrm6: Don't call icmpv6_send on local error") Signed-off-by: Thadeu Lima de Souza Cascardo Reviewed-by: Sabrina Dubroca Signed-off-by: Steffen Klassert --- net/ipv6/xfrm6_output.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c index 5959ce9620eb..6a74080005cf 100644 --- a/net/ipv6/xfrm6_output.c +++ b/net/ipv6/xfrm6_output.c @@ -170,9 +170,11 @@ static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb) if (toobig && xfrm6_local_dontfrag(skb)) { xfrm6_local_rxpmtu(skb, mtu); + kfree_skb(skb); return -EMSGSIZE; } else if (!skb->ignore_df && toobig && skb->sk) { xfrm_local_error(skb, mtu); + kfree_skb(skb); return -EMSGSIZE; } -- 2.17.1