From: Jens Axboe <axboe@kernel.dk>
Date: Fri, 15 Jan 2021 23:04:23 +0000 (-0700)
Subject: io_uring: ensure finish_wait() is always called in __io_uring_task_cancel()
X-Git-Tag: baikal/aarch64/sdk6.1~7459^2
X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=ce70c0f9b472a910cb22b177e904d6f7cbd0d194;p=kernel.git

io_uring: ensure finish_wait() is always called in __io_uring_task_cancel()

If we enter with requests pending and performm cancelations, we'll have
a different inflight count before and after calling prepare_to_wait().
This causes the loop to restart. If we actually ended up canceling
everything, or everything completed in-between, then we'll break out
of the loop without calling finish_wait() on the waitqueue. This can
trigger a warning on exit_signals(), as we leave the task state in
TASK_UNINTERRUPTIBLE.

Put a finish_wait() after the loop to catch that case.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 06cc79d39586d..985a9e3f976d3 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -9101,6 +9101,7 @@ void __io_uring_task_cancel(void)
 		finish_wait(&tctx->wait, &wait);
 	} while (1);
 
+	finish_wait(&tctx->wait, &wait);
 	atomic_dec(&tctx->in_idle);
 
 	io_uring_remove_task_files(tctx);