[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20221101021706.26152-3-decui@microsoft.com>
Date: Mon, 31 Oct 2022 19:17:06 -0700
From: Dexuan Cui <decui@...rosoft.com>
To: sgarzare@...hat.com, davem@...emloft.net, edumazet@...gle.com,
kuba@...nel.org, pabeni@...hat.com, arseny.krasnov@...persky.com,
netdev@...r.kernel.org
Cc: virtualization@...ts.linux-foundation.org,
linux-kernel@...r.kernel.org, kys@...rosoft.com,
haiyangz@...rosoft.com, stephen@...workplumber.org,
wei.liu@...nel.org, linux-hyperv@...r.kernel.org,
Dexuan Cui <decui@...rosoft.com>
Subject: [PATCH v2 2/2] vsock: fix possible infinite sleep in vsock_connectible_wait_data()
Currently vsock_connectible_has_data() may miss a wakeup operation
between vsock_connectible_has_data() == 0 and the prepare_to_wait().
Fix the race by adding the process to the wait queue before checking
vsock_connectible_has_data().
Fixes: b3f7fd54881b ("af_vsock: separate wait data loop")
Signed-off-by: Dexuan Cui <decui@...rosoft.com>
---
Changes in v2 (Thanks Stefano!):
Fixed a typo in the commit message.
Removed the unnecessary finish_wait() at the end of the loop.
net/vmw_vsock/af_vsock.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index d258fd43092e..884eca7f6743 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1905,8 +1905,11 @@ static int vsock_connectible_wait_data(struct sock *sk,
err = 0;
transport = vsk->transport;
- while ((data = vsock_connectible_has_data(vsk)) == 0) {
+ while (1) {
prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE);
+ data = vsock_connectible_has_data(vsk);
+ if (data != 0)
+ break;
if (sk->sk_err != 0 ||
(sk->sk_shutdown & RCV_SHUTDOWN) ||
--
2.25.1
Powered by blists - more mailing lists