GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-03-18 13:04:18 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

mptcp: do not wakeup listener for MPJ subflows

Browse source 
MPJ subflows are not exposed as fds to user spaces. As such,
incoming MPJ subflows are removed from the accept queue by
tcp_check_req()/tcp_get_cookie_sock().

Later tcp_child_process() invokes subflow_data_ready() on the
parent socket regardless of the subflow kind, leading to poll
wakeups even if the later accept will block.

Address the issue by double-checking the queue state before
waking the user-space.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/164
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Paolo Abeni 2021-02-19 18:35:40 +01:00 • committed by Jakub Kicinski
parent ad98dd3705
commit 52557dbc75
1 changed files with 6 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
net/mptcp/subflow.c
View file

@ -1096,6 +1096,12 @@ static void subflow_data_ready(struct sock *sk)
msk = mptcp_sk(parent);
if (state & TCPF_LISTEN) {
/* MPJ subflow are removed from accept queue before reaching here,
* avoid stray wakeups
*/
if (reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue))
return;
set_bit(MPTCP_DATA_READY, &msk->flags);
parent->sk_data_ready(parent);
return;