2018-02-01 21:23 GMT+02:00 Neil Horman <nhorman@xxxxxxxxxxxxx>: > No, I can't say I saw the patch on the list. Can you resend it? Here's the patch again, sending from gmail this time. The previous mail is now also at spinics, dunno what happened. https://www.spinics.net/lists/linux-sctp/msg07005.html >From b94c037d27e36a3053e6862b7e7da5f07f2f5597 Mon Sep 17 00:00:00 2001 From: Tommi Rantala <tommi.t.rantala@xxxxxxxxx> Date: Wed, 31 Jan 2018 11:24:31 +0000 Subject: [PATCH] sctp: fix dst leak in sctp_v4_get_dst Fix dst reference leak in sctp_v4_get_dst() introduced in commit 410f03831 ("sctp: add routing output fallback"): When walking the address_list, successive ip_route_output_key() calls may return the same rt->dst with the reference incremented on each call. The code would not decrement the dst refcount when the dst pointer was identical from the previous iteration, causing the dst leak. Testcase: ip netns add TEST ip netns exec TEST ip link set lo up ip link add dummy0 type dummy ip link add dummy1 type dummy ip link add dummy2 type dummy ip link set dev dummy0 netns TEST ip link set dev dummy1 netns TEST ip link set dev dummy2 netns TEST ip netns exec TEST ip addr add 192.168.1.1/24 dev dummy0 ip netns exec TEST ip link set dummy0 up ip netns exec TEST ip addr add 192.168.1.2/24 dev dummy1 ip netns exec TEST ip link set dummy1 up ip netns exec TEST ip addr add 192.168.1.3/24 dev dummy2 ip netns exec TEST ip link set dummy2 up ip netns exec TEST sctp_test -H 192.168.1.2 -P 20002 -h 192.168.1.1 -p 20000 -s -B 192.168.1.3 ip netns del TEST In 4.4 and 4.9 kernels this results to: [ 354.179591] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 364.419674] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 374.663664] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 384.903717] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 395.143724] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 405.383645] unregister_netdevice: waiting for lo to become free. Usage count = 1 ... Fixes: 410f03831 ("sctp: add routing output fallback") Signed-off-by: Tommi Rantala <tommi.t.rantala@xxxxxxxxx> --- net/sctp/protocol.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 8b4ff315695e..aadb9e7f60e2 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -508,21 +508,20 @@ static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr, if (IS_ERR(rt)) continue; - if (!dst) - dst = &rt->dst; - /* Ensure the src address belongs to the output * interface. */ odev = __ip_dev_find(sock_net(sk), laddr->a.v4.sin_addr.s_addr, false); if (!odev || odev->ifindex != fl4->flowi4_oif) { - if (&rt->dst != dst) + if (!dst) + dst = &rt->dst; + else dst_release(&rt->dst); continue; } - if (dst != &rt->dst) + if (dst && dst != &rt->dst) dst_release(dst); dst = &rt->dst; break; -- 2.15.1 -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
