diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2023-10-11 09:20:55 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-10-13 16:49:32 -0700 |
| commit | 419ce133ab928ab5efd7b50b2ef36ddfd4eadbd2 (patch) | |
| tree | 8d934593e6eaf8f7ded2c7c32e8bd0db8effccd9 /net/mptcp/protocol.c | |
| parent | 242e34500a32631f85c2b4eb6cb42a368a39e54f (diff) | |
tcp: allow again tcp_disconnect() when threads are waiting
As reported by Tom, .NET and applications build on top of it rely
on connect(AF_UNSPEC) to async cancel pending I/O operations on TCP
socket.
The blamed commit below caused a regression, as such cancellation
can now fail.
As suggested by Eric, this change addresses the problem explicitly
causing blocking I/O operation to terminate immediately (with an error)
when a concurrent disconnect() is executed.
Instead of tracking the number of threads blocked on a given socket,
track the number of disconnect() issued on such socket. If such counter
changes after a blocking operation releasing and re-acquiring the socket
lock, error out the current operation.
Fixes: 4faeee0cf8a5 ("tcp: deny tcp_disconnect() when threads are waiting")
Reported-by: Tom Deseyn <tdeseyn@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1886305
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/f3b95e47e3dbed840960548aebaa8d954372db41.1697008693.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/mptcp/protocol.c')
| -rw-r--r-- | net/mptcp/protocol.c | 7 |
1 files changed, 0 insertions, 7 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index c3b83cb390d9..d1902373c974 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -3098,12 +3098,6 @@ static int mptcp_disconnect(struct sock *sk, int flags) { struct mptcp_sock *msk = mptcp_sk(sk); - /* Deny disconnect if other threads are blocked in sk_wait_event() - * or inet_wait_for_connect(). - */ - if (sk->sk_wait_pending) - return -EBUSY; - /* We are on the fastopen error path. We can't call straight into the * subflows cleanup code due to lock nesting (we are already under * msk->firstsocket lock). @@ -3173,7 +3167,6 @@ struct sock *mptcp_sk_clone_init(const struct sock *sk, inet_sk(nsk)->pinet6 = mptcp_inet6_sk(nsk); #endif - nsk->sk_wait_pending = 0; __mptcp_init_sock(nsk); msk = mptcp_sk(nsk); |