[moderation] [kernel?] KCSAN: data-race in do_mq_timedreceive / msg_insert (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e67572cd2204 Linux 6.9-rc6
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14154a40980000
kernel config: https://syzkaller.appspot.com/x/.config?x=c3beef2aff822313
dashboard link: https://syzkaller.appspot.com/bug?extid=2d7f8c2032c990c518a8
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/7b20866b5f53/disk-e67572cd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4c1441ce05e8/vmlinux-e67572cd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/382a9e170b40/bzImage-e67572cd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2d7f8c...@syzkaller.appspotmail.com

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

write to 0xffff888104782458 of 8 bytes by task 10469 on cpu 0:
msg_insert+0x10a/0x2e0 ipc/mqueue.c:212
do_mq_timedsend+0x471/0xa10 ipc/mqueue.c:1161
__do_sys_mq_timedsend ipc/mqueue.c:1294 [inline]
__se_sys_mq_timedsend ipc/mqueue.c:1283 [inline]
__x64_sys_mq_timedsend+0xca/0x150 ipc/mqueue.c:1283
x64_sys_call+0xcd7/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:243
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888104782458 of 8 bytes by task 10467 on cpu 1:
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
x64_sys_call+0x2c3f/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:244
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811739fec0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10467 Comm: syz-executor.4 Tainted: G W 6.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================


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