[moderation] [fs?] KCSAN: data-race in inode_update_timestamps / inode_update_timestamps (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b850dc206a57 Merge tag 'firewire-updates-6.10' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1067895c980000
kernel config: https://syzkaller.appspot.com/x/.config?x=73edb1d83ffa7e34
dashboard link: https://syzkaller.appspot.com/bug?extid=33da257fe0b2bf79265a
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/30d7605d7fd8/disk-b850dc20.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/aab977699473/vmlinux-b850dc20.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5122c56c1adf/bzImage-b850dc20.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+33da25...@syzkaller.appspotmail.com

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

write to 0xffff888119d107d0 of 8 bytes by task 9834 on cpu 1:
inode_set_ctime_to_ts include/linux/fs.h:1623 [inline]
inode_set_ctime_current fs/inode.c:2515 [inline]
inode_update_timestamps+0xb5/0x280 fs/inode.c:1861
generic_update_time fs/inode.c:1900 [inline]
inode_update_time fs/inode.c:1920 [inline]
__file_update_time fs/inode.c:2109 [inline]
file_update_time+0x22f/0x2c0 fs/inode.c:2139
pipe_write+0xa87/0xd30 fs/pipe.c:607
call_write_iter include/linux/fs.h:2120 [inline]
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0x765/0x8e0 fs/read_write.c:590
ksys_write+0xeb/0x1b0 fs/read_write.c:643
__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
x64_sys_call+0x27b7/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:2
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 0xffff888119d107d0 of 8 bytes by task 24349 on cpu 0:
inode_get_ctime include/linux/fs.h:1617 [inline]
inode_update_timestamps+0x59/0x280 fs/inode.c:1858
generic_update_time fs/inode.c:1900 [inline]
inode_update_time fs/inode.c:1920 [inline]
__file_update_time fs/inode.c:2109 [inline]
file_update_time+0x22f/0x2c0 fs/inode.c:2139
pipe_write+0xa87/0xd30 fs/pipe.c:607
__kernel_write_iter+0x24e/0x4a0 fs/read_write.c:523
__kernel_write fs/read_write.c:543 [inline]
kernel_write+0x1f3/0x410 fs/read_write.c:564
p9_fd_write net/9p/trans_fd.c:432 [inline]
p9_write_work+0x32a/0x750 net/9p/trans_fd.c:483
process_one_work kernel/workqueue.c:3267 [inline]
process_scheduled_works+0x465/0x990 kernel/workqueue.c:3348
worker_thread+0x526/0x730 kernel/workqueue.c:3429
kthread+0x1d1/0x210 kernel/kthread.c:389
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x000000001efe9456 -> 0x000000002625a257

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 24349 Comm: kworker/0:0 Tainted: G W 6.9.0-syzkaller-03117-gb850dc206a57 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: events p9_write_work
==================================================================
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: port 2(bridge_slave_1) entered disabled state


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