[moderation] [io-uring?] KCSAN: data-race in __io_commit_cqring_flush / io_submit_sqes

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8a92980606e3 Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1226f626980000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c00b51a1d411353
dashboard link: https://syzkaller.appspot.com/bug?extid=f99c8b5c962def815ea1
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/b0932ad98ab1/disk-8a929806.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/243f1993fb5f/vmlinux-8a929806.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8c13ddeac75d/bzImage-8a929806.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f99c8b...@syzkaller.appspotmail.com

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

read-write to 0xffff888131ecb004 of 2 bytes by task 15551 on cpu 0:
io_init_req_drain io_uring/io_uring.c:2022 [inline]
io_init_req io_uring/io_uring.c:2081 [inline]
io_submit_sqe io_uring/io_uring.c:2182 [inline]
io_submit_sqes+0xb7a/0x1070 io_uring/io_uring.c:2335
__do_sys_io_uring_enter io_uring/io_uring.c:3244 [inline]
__se_sys_io_uring_enter+0x1c6/0x15a0 io_uring/io_uring.c:3181
__x64_sys_io_uring_enter+0x78/0x90 io_uring/io_uring.c:3181
x64_sys_call+0x25ab/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:427
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 0xffff888131ecb004 of 2 bytes by task 15554 on cpu 1:
__io_commit_cqring_flush+0x20/0x1c0 io_uring/io_uring.c:624
io_commit_cqring_flush io_uring/io_uring.h:364 [inline]
io_cq_unlock_post io_uring/io_uring.c:668 [inline]
io_req_complete_post io_uring/io_uring.c:939 [inline]
io_issue_sqe+0x8d6/0xc80 io_uring/io_uring.c:1763
io_wq_submit_work+0x42b/0x5a0 io_uring/io_uring.c:1860
io_worker_handle_work+0x45a/0x9a0 io_uring/io-wq.c:597
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: 0x0100 -> 0x0109

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15554 Comm: iou-wrk-15551 Not tainted 6.10.0-rc2-syzkaller-00235-g8a92980606e3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
==================================================================


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