[syzbot] [io-uring?] KCSAN: data-race in io_worker_handle_work / io_wq_worker_cancel (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2ccbdf43d5e7 Merge tag 'for-linus' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1408060e980000
kernel config: https://syzkaller.appspot.com/x/.config?x=68336ea4b6f4fc09
dashboard link: https://syzkaller.appspot.com/bug?extid=90b0e38244e035ec327c
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/26ed33651516/disk-2ccbdf43.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3c0b763ac146/vmlinux-2ccbdf43.xz
kernel image: https://storage.googleapis.com/syzbot-assets/be99b90037ed/bzImage-2ccbdf43.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+90b0e3...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in io_worker_handle_work / io_wq_worker_cancel

read-write to 0xffff8881070473d8 of 4 bytes by task 24619 on cpu 0:
__io_wq_worker_cancel io_uring/io-wq.c:993 [inline]
io_wq_worker_cancel+0x70/0x140 io_uring/io-wq.c:1010
io_wq_for_each_worker+0x116/0x200 io_uring/io-wq.c:874
io_wq_cancel_running_work io_uring/io-wq.c:1080 [inline]
io_wq_cancel_cb+0x10d/0x190 io_uring/io-wq.c:1111
io_async_cancel_one io_uring/cancel.c:87 [inline]
__io_async_cancel+0x176/0x270 io_uring/cancel.c:187
__io_sync_cancel io_uring/cancel.c:261 [inline]
io_sync_cancel+0x5a6/0x6d0 io_uring/cancel.c:325
__io_uring_register io_uring/register.c:543 [inline]
__do_sys_io_uring_register io_uring/register.c:616 [inline]
__se_sys_io_uring_register+0x504/0x1190 io_uring/register.c:577
__x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:577
x64_sys_call+0x2c2/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:428
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881070473d8 of 4 bytes by task 24621 on cpu 1:
io_get_work_hash io_uring/io-wq.c:454 [inline]
io_worker_handle_work+0x41a/0x9a0 io_uring/io-wq.c:591
io_wq_worker+0x286/0x820 io_uring/io-wq.c:651
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 24621 Comm: iou-wrk-24619 Not tainted 6.10.0-rc3-syzkaller-00044-g2ccbdf43d5e7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================


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