From: Thadeu Lima de Souza Cascardo Date: Fri, 31 Aug 2018 11:38:49 +0000 (-0300) Subject: xfrm6: call kfree_skb when skb is toobig X-Git-Tag: v4.14.79~142 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=2a55e64d5c5e98e425f7eafd2c480440b4aa78c2;p=users%2Fjedix%2Flinux-maple.git xfrm6: call kfree_skb when skb is toobig [ 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 --- diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c index 8ae87d4ec5ff6..29dae7f2ff14d 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; }