[moderation] [kernel?] KCSAN: data-race in do_mq_timedreceive / do_mq_timedreceive

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dba89d1b81df Merge tag 'docs-6.9-2' of git://git.lwn.net/l..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12fc1531180000
kernel config: https://syzkaller.appspot.com/x/.config?x=8e033e6bf1fa349a
dashboard link: https://syzkaller.appspot.com/bug?extid=a0e694e8028ad532d47c
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [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/4bfd121c5b45/disk-dba89d1b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e1b090399db0/vmlinux-dba89d1b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3fe63dba9796/bzImage-dba89d1b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a0e694...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in do_mq_timedreceive / do_mq_timedreceive

write to 0xffff888100e68dd8 of 8 bytes by task 6195 on cpu 1:
do_mq_timedreceive+0x289/0x6e0 ipc/mqueue.c:1238
__do_sys_mq_timedreceive ipc/mqueue.c:1308 [inline]
__se_sys_mq_timedreceive ipc/mqueue.c:1297 [inline]
__x64_sys_mq_timedreceive+0xca/0x150 ipc/mqueue.c:1297
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

read to 0xffff888100e68dd8 of 8 bytes by task 6198 on cpu 0:
do_mq_timedreceive+0x207/0x6e0 ipc/mqueue.c:1230
__do_sys_mq_timedreceive ipc/mqueue.c:1308 [inline]
__se_sys_mq_timedreceive ipc/mqueue.c:1297 [inline]
__x64_sys_mq_timedreceive+0xca/0x150 ipc/mqueue.c:1297
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

value changed: 0x0000000000000000 -> 0xffff88815ef42d80

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6198 Comm: syz-executor.2 Tainted: G W 6.8.0-syzkaller-11752-gdba89d1b81df #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.