| Message ID | 20180831113849.19909-1-cascardo@canonical.com |
|---|---|
| State | Awaiting Upstream, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | [v2] xfrm6: call kfree_skb when skb is toobig | expand |
On Fri, Aug 31, 2018 at 08:38:49AM -0300, Thadeu Lima de Souza Cascardo wrote: > 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. > > Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> > Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> > Fixes: dd767856a36e ("xfrm6: Don't call icmpv6_send on local error") Applied, thanks a lot!
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; }
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. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Fixes: dd767856a36e ("xfrm6: Don't call icmpv6_send on local error") --- net/ipv6/xfrm6_output.c | 2 ++ 1 file changed, 2 insertions(+)