[moderation] [io-uring?] KCSAN: data-race in __se_sys_io_uring_register / io_sqe_buffers_unregister

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1f440397665f Merge tag 'docs-6.9' of git://git.lwn.net/linux
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1292f78e180000
kernel config: https://syzkaller.appspot.com/x/.config?x=7d0d3745a0ef979d
dashboard link: https://syzkaller.appspot.com/bug?extid=18b8783ec00f525f7581
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/216d31101980/disk-1f440397.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7cdbd9d14799/vmlinux-1f440397.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c8c0ef56d857/bzImage-1f440397.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+18b878...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __se_sys_io_uring_register / io_sqe_buffers_unregister

read-write to 0xffff8881209d68bc of 4 bytes by task 27699 on cpu 1:
io_sqe_buffers_unregister+0x5b/0xb0 io_uring/rsrc.c:798
__io_uring_register io_uring/register.c:424 [inline]
__do_sys_io_uring_register io_uring/register.c:613 [inline]
__se_sys_io_uring_register+0xac2/0x11a0 io_uring/register.c:574
__x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:574
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

read to 0xffff8881209d68bc of 4 bytes by task 27698 on cpu 0:
__do_sys_io_uring_register io_uring/register.c:615 [inline]
__se_sys_io_uring_register+0xaee/0x11a0 io_uring/register.c:574
__x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:574
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27698 Comm: syz-executor.2 Not tainted 6.8.0-syzkaller-02737-g1f440397665f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
==================================================================


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[syzbot]

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