On close this timer might be scheduled. mptcp uses sk_reset_timer for
this, so the a reference on the mptcp socket is taken.
This causes a refcount leak which can for example be reproduced
with 'mp_join_server_v4.pkt' from the mptcp-packetdrill repo.
The leak has nothing to do with join requests, v1_mp_capable_bind_no_cs.pkt
works too when replacing the last ack mpcapable to v1 instead of v0.
unreferenced object 0xffff888109bba040 (size 2744):
comm "packetdrill", [..]
backtrace:
[..] sk_prot_alloc.isra.0+0x2b/0xc0
[..] sk_clone_lock+0x2f/0x740
[..] mptcp_sk_clone+0x33/0x1a0
[..] subflow_syn_recv_sock+0x2b1/0x690 [..]
Fixes: e16163b6e2b7 ("mptcp: refactor shutdown and close")
Cc: Paolo Abeni <[email protected]>
Cc: Davide Caratti <[email protected]>
Signed-off-by: Florian Westphal <[email protected]>
---
net/mptcp/protocol.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 4b7794835fea..dc979571f561 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1710,6 +1710,7 @@ static void mptcp_timeout_timer(struct timer_list *t)
struct sock *sk = from_timer(sk, t, sk_timer);
mptcp_schedule_work(sk);
+ sock_put(sk);
}
/* Find an idle subflow. Return NULL if there is unacked data at tcp
--
2.26.2
