[moderation] [fs?] KCSAN: data-race in ksys_write / ksys_write (13)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9f16d5e6f220 Merge tag 'for-linus' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=150459c0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3d7fd5be0e73b8b
dashboard link: https://syzkaller.appspot.com/bug?extid=1b1b9dcd18fc25da8f7d
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9fa7a64f26d5/disk-9f16d5e6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/800b086e8afd/vmlinux-9f16d5e6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/21f5373315cb/bzImage-9f16d5e6.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1b1b9d...@syzkaller.appspotmail.com

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

write to 0xffff88811674b070 of 8 bytes by task 8890 on cpu 1:
ksys_write+0x11b/0x1b0 fs/read_write.c:733
__do_sys_write fs/read_write.c:742 [inline]
__se_sys_write fs/read_write.c:739 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:739
x64_sys_call+0x287e/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:2
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

write to 0xffff88811674b070 of 8 bytes by task 8891 on cpu 0:
ksys_write+0x11b/0x1b0 fs/read_write.c:733
__do_sys_write fs/read_write.c:742 [inline]
__se_sys_write fs/read_write.c:739 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:739
x64_sys_call+0x287e/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:2
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: 0x0000000000000000 -> 0x000000000000000b

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8891 Comm: syz.2.1842 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================


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[syzbot]

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