[syzbot] [kernel?] KCSAN: data-race in do_mq_timedreceive / msg_insert (4)

[syzbot <syzbot+2ba73bf53a28c019b9b1@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    0c559323bbaa Merge tag 'rust-fixes-6.12' of https://github..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13fc0d80580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=95098faba89c70c9
dashboard link: https://syzkaller.appspot.com/bug?extid=2ba73bf53a28c019b9b1
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/415934cb0f6d/disk-0c559323.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/19b092990019/vmlinux-0c559323.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6e86fa4c4df0/bzImage-0c559323.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2ba73bf53a28c019b9b1@syzkaller.appspotmail.com

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

write to 0xffff888114787e90 of 8 bytes by task 9929 on cpu 1:
 msg_insert+0x10a/0x2e0 ipc/mqueue.c:212
 do_mq_timedsend+0x465/0xa00 ipc/mqueue.c:1162
 __do_sys_mq_timedsend ipc/mqueue.c:1295 [inline]
 __se_sys_mq_timedsend ipc/mqueue.c:1284 [inline]
 __x64_sys_mq_timedsend+0xca/0x150 ipc/mqueue.c:1284
 x64_sys_call+0x26c5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:243
 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 0xffff888114787e90 of 8 bytes by task 9924 on cpu 0:
 do_mq_timedreceive+0x1fb/0x6d0 ipc/mqueue.c:1231
 __do_sys_mq_timedreceive ipc/mqueue.c:1309 [inline]
 __se_sys_mq_timedreceive ipc/mqueue.c:1298 [inline]
 __x64_sys_mq_timedreceive+0xca/0x150 ipc/mqueue.c:1298
 x64_sys_call+0xccf/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:244
 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

value changed: 0xffff888134b65740 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9924 Comm: syz.0.1959 Tainted: G        W          6.12.0-rc1-syzkaller-00125-g0c559323bbaa #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================


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