[moderation] [fs?] KCSAN: data-race in ksys_write / ksys_write (12)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6613476e225e Linux 6.8-rc1
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=143cd777e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=5197e0a6c8448ad3
dashboard link: https://syzkaller.appspot.com/bug?extid=aea4865ae5110da08e20
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/61d720b37887/disk-6613476e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d122725c1ed5/vmlinux-6613476e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/85b4e6b79b60/bzImage-6613476e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+aea486...@syzkaller.appspotmail.com

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

write to 0xffff88813ede1640 of 8 bytes by task 20994 on cpu 1:
ksys_write+0x11e/0x1a0 fs/read_write.c:645
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:652
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff88813ede1640 of 8 bytes by task 20992 on cpu 0:
ksys_write+0xad/0x1a0 fs/read_write.c:640
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:652
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000364 -> 0x0000000000000c6a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20992 Comm: syz-executor.2 Not tainted 6.8.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================


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[syzbot]

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