KCSAN: data-race in io_submit_sqes / io_uring_poll (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a9c9a6f741cd Merge tag 'scsi-misc' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=108e9d5d300000
kernel config: https://syzkaller.appspot.com/x/.config?x=75bfe5e684a66244
dashboard link: https://syzkaller.appspot.com/bug?extid=e7323a289b935b39b650
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1
CC: [asml.s...@gmail.com ax...@kernel.dk io-u...@vger.kernel.org linux-...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e7323a...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in io_submit_sqes / io_uring_poll

write to 0xffff88813d838870 of 4 bytes by task 9448 on cpu 0:
io_get_sqe fs/io_uring.c:7147 [inline]
io_submit_sqes+0x493/0xde0 fs/io_uring.c:7190
__do_sys_io_uring_enter fs/io_uring.c:9839 [inline]
__se_sys_io_uring_enter+0x213/0xae0 fs/io_uring.c:9781
__x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:9781
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88813d838870 of 4 bytes by task 9444 on cpu 1:
io_sqring_full fs/io_uring.c:1559 [inline]
io_uring_poll+0x8e/0x150 fs/io_uring.c:9169
vfs_poll include/linux/poll.h:90 [inline]
io_poll_rewait fs/io_uring.c:5206 [inline]
io_poll_task_func+0x11a/0x5b0 fs/io_uring.c:5283
tctx_task_work+0x233/0x490 fs/io_uring.c:2143
task_work_run+0xae/0x130 kernel/task_work.c:164
tracehook_notify_signal include/linux/tracehook.h:212 [inline]
io_run_task_work fs/io_uring.c:2403 [inline]
io_run_task_work_sig fs/io_uring.c:7426 [inline]
io_ctx_quiesce fs/io_uring.c:10565 [inline]
__io_uring_register fs/io_uring.c:10598 [inline]
__do_sys_io_uring_register+0x40b/0x1fc0 fs/io_uring.c:10736
__se_sys_io_uring_register fs/io_uring.c:10716 [inline]
__x64_sys_io_uring_register+0x4f/0x60 fs/io_uring.c:10716
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x000037d1 -> 0x000037e0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9444 Comm: syz-executor.1 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.