| From a298232ee6b9a1d5d732aa497ff8be0d45b5bd82 Mon Sep 17 00:00:00 2001 |
| From: Pavel Begunkov <asml.silence@gmail.com> |
| Date: Fri, 7 May 2021 21:06:38 +0100 |
| Subject: io_uring: fix link timeout refs |
| |
| From: Pavel Begunkov <asml.silence@gmail.com> |
| |
| commit a298232ee6b9a1d5d732aa497ff8be0d45b5bd82 upstream. |
| |
| WARNING: CPU: 0 PID: 10242 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 |
| RIP: 0010:refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 |
| Call Trace: |
| __refcount_sub_and_test include/linux/refcount.h:283 [inline] |
| __refcount_dec_and_test include/linux/refcount.h:315 [inline] |
| refcount_dec_and_test include/linux/refcount.h:333 [inline] |
| io_put_req fs/io_uring.c:2140 [inline] |
| io_queue_linked_timeout fs/io_uring.c:6300 [inline] |
| __io_queue_sqe+0xbef/0xec0 fs/io_uring.c:6354 |
| io_submit_sqe fs/io_uring.c:6534 [inline] |
| io_submit_sqes+0x2bbd/0x7c50 fs/io_uring.c:6660 |
| __do_sys_io_uring_enter fs/io_uring.c:9240 [inline] |
| __se_sys_io_uring_enter+0x256/0x1d60 fs/io_uring.c:9182 |
| |
| io_link_timeout_fn() should put only one reference of the linked timeout |
| request, however in case of racing with the master request's completion |
| first io_req_complete() puts one and then io_put_req_deferred() is |
| called. |
| |
| Cc: stable@vger.kernel.org # 5.12+ |
| Fixes: 9ae1f8dd372e0 ("io_uring: fix inconsistent lock state") |
| Reported-by: syzbot+a2910119328ce8e7996f@syzkaller.appspotmail.com |
| Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> |
| Link: https://lore.kernel.org/r/ff51018ff29de5ffa76f09273ef48cb24c720368.1620417627.git.asml.silence@gmail.com |
| Signed-off-by: Jens Axboe <axboe@kernel.dk> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| fs/io_uring.c | 1 - |
| 1 file changed, 1 deletion(-) |
| |
| --- a/fs/io_uring.c |
| +++ b/fs/io_uring.c |
| @@ -6307,7 +6307,6 @@ static enum hrtimer_restart io_link_time |
| } else { |
| io_req_complete_post(req, -ETIME, 0); |
| } |
| - io_put_req_deferred(req, 1); |
| return HRTIMER_NORESTART; |
| } |
| |