[PATCH 5.10 38/67] tipc: fix sleeping in tipc accept routine

Greg Kroah-Hartman
2021-08-02T14:00:26Z

From: Hoang Le <hoang.h.le@dektech.com.au>

[ Upstream commit d237a7f11719ff9320721be5818352e48071aab6 ]

The release_sock() is blocking function, it would change the state
after sleeping. In order to evaluate the stated condition outside
the socket lock context, switch to use wait_woken() instead.

Fixes: 6398e23cdb1d8 ("tipc: standardize accept routine")
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/tipc/socket.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 694c432b9710..4f9bd95b4eee 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -2650,7 +2650,7 @@ static int tipc_listen(struct socket *sock, int len)
static int tipc_wait_for_accept(struct socket *sock, long timeo)
{
struct sock *sk = sock->sk;
- DEFINE_WAIT(wait);
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
int err;

/* True wake-one mechanism for incoming connections: only
@@ -2659,12 +2659,12 @@ static int tipc_wait_for_accept(struct socket *sock, long timeo)
* anymore, the common case will execute the loop only once.
*/
for (;;) {
- prepare_to_wait_exclusive(sk_sleep(sk), &wait,
- TASK_INTERRUPTIBLE);
if (timeo && skb_queue_empty(&sk->sk_receive_queue)) {
+ add_wait_queue(sk_sleep(sk), &wait);
release_sock(sk);
- timeo = schedule_timeout(timeo);
+ timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
lock_sock(sk);
+ remove_wait_queue(sk_sleep(sk), &wait);
}
err = 0;
if (!skb_queue_empty(&sk->sk_receive_queue))
@@ -2676,7 +2676,6 @@ static int tipc_wait_for_accept(struct socket *sock, long timeo)
if (signal_pending(current))
break;
}
- finish_wait(sk_sleep(sk), &wait);
return err;
}

--
2.30.2