On Wed, Oct 02, 2024 at 05:50:25AM -0700, Jakub Kicinski wrote:
On Wed, 25 Sep 2024 08:07:54 -0400 Sasha Levin wrote:
From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
[ 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.
I wouldn't backport this, it may cause perf regressions.
Dropped, thanks!
--
Thanks,
Sasha
