From: Sascha Hauer s.hauer@pengutronix.de
[ Upstream commit 54001d0f2fdbc7852136a00f3e6fc395a9547ae5 ]
When asynchronous encryption is used KTLS sends out the final data at proto->close time. This becomes problematic when the task calling close() receives a signal. In this case it can happen that tcp_sendmsg_locked() called at close time returns -ERESTARTSYS and the final data is not sent.
The described situation happens when KTLS is used in conjunction with io_uring, as io_uring uses task_work_add() to add work to the current userspace task. A discussion of the problem along with a reproducer can be found in [1] and [2]
Fix this by waiting for the asynchronous encryption to be completed on the final message. With this there is no data left to be sent at close time.
[1] https://lore.kernel.org/all/20231010141932.GD3114228@pengutronix.de/ [2] https://lore.kernel.org/all/20240315100159.3898944-1-s.hauer@pengutronix.de/
Signed-off-by: Sascha Hauer s.hauer@pengutronix.de Link: https://patch.msgid.link/20240904-ktls-wait-async-v1-1-a62892833110@pengutro... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/tls/tls_sw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index df166f6afad82..904dae0df7a47 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1201,7 +1201,7 @@ static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg,
if (!num_async) { goto send_end; - } else if (num_zc) { + } else if (num_zc || eor) { int err;
/* Wait for pending encryptions to get completed */