From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thadeu Lima de Souza Cascardo , Sabrina Dubroca , Steffen Klassert , Sasha Levin Subject: [PATCH 4.4 002/114] xfrm6: call kfree_skb when skb is toobig Date: Thu, 8 Nov 2018 13:50:17 -0800 Message-Id: <20181108215059.222969078@linuxfoundation.org> In-Reply-To: <20181108215059.051093652@linuxfoundation.org> References: <20181108215059.051093652@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 215ab0f021c9fea3c18b75e7d522400ee6a49990 ] 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 Signed-off-by: Sasha Levin --- 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 4d09ce6fa90e..64862c5084ee 100644 --- a/net/ipv6/xfrm6_output.c +++ b/net/ipv6/xfrm6_output.c @@ -165,9 +165,11 @@ 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