[moderation] [io-uring?] KCSAN: data-race in io_sq_thread / io_uring_try_cancel_requests (12)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 62b5a46999c7 Merge tag '6.13-rc1-smb3-client-fixes' of git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13b0c8f8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ff022027cd3a0001
dashboard link: https://syzkaller.appspot.com/bug?extid=3c750be01dab672c513d
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
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.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d886c5d5e278/disk-62b5a469.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0303aa72049c/vmlinux-62b5a469.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5706a95aa0b0/bzImage-62b5a469.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3c750b...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in io_sq_thread / io_uring_try_cancel_requests

write to 0xffff88811b3af3f8 of 8 bytes by task 7162 on cpu 1:
io_sq_thread+0xe68/0x10b0 io_uring/sqpoll.c:378
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff88811b3af3f8 of 8 bytes by task 36 on cpu 0:
io_uring_try_cancel_requests+0x18d/0x340 io_uring/io_uring.c:3095
io_ring_exit_work+0x148/0x500 io_uring/io_uring.c:2897
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310
worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391
kthread+0x1d1/0x210 kernel/kthread.c:389
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: 0xffff888102853180 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted 6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: iou_exit io_ring_exit_work
==================================================================


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