[moderation] [kernfs?] KCSAN: data-race in kernfs_iop_permission / kernfs_iop_permission (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4a7bbe7519b6 Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1483dde0180000
kernel config: https://syzkaller.appspot.com/x/.config?x=3cd0dc1b46a5bc5c
dashboard link: https://syzkaller.appspot.com/bug?extid=a8aabd0ec670cb644078
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [gre...@linuxfoundation.org linux-...@vger.kernel.org linux-...@vger.kernel.org t...@kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/903440c61bef/disk-4a7bbe75.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9655b05e2f2b/vmlinux-4a7bbe75.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4a4529a3d03b/bzImage-4a7bbe75.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a8aabd...@syzkaller.appspotmail.com

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

write to 0xffff88810572c7b8 of 8 bytes by task 2774 on cpu 0:
inode_set_mtime_to_ts include/linux/fs.h:1571 [inline]
set_inode_attr fs/kernfs/inode.c:163 [inline]
kernfs_refresh_inode fs/kernfs/inode.c:177 [inline]
kernfs_iop_permission+0x13f/0x220 fs/kernfs/inode.c:288
do_inode_permission fs/namei.c:462 [inline]
inode_permission+0x184/0x300 fs/namei.c:529
may_lookup fs/namei.c:1723 [inline]
link_path_walk+0x19e/0x7e0 fs/namei.c:2270
path_lookupat+0x72/0x2a0 fs/namei.c:2481
filename_lookup+0x126/0x300 fs/namei.c:2511
vfs_statx+0xa2/0x320 fs/stat.c:244
vfs_fstatat+0xcd/0x100 fs/stat.c:304
__do_sys_newfstatat fs/stat.c:468 [inline]
__se_sys_newfstatat+0x58/0x260 fs/stat.c:462
__x64_sys_newfstatat+0x55/0x60 fs/stat.c:462
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+0x63/0x6b

write to 0xffff88810572c7b8 of 8 bytes by task 3270 on cpu 1:
inode_set_mtime_to_ts include/linux/fs.h:1571 [inline]
set_inode_attr fs/kernfs/inode.c:163 [inline]
kernfs_refresh_inode fs/kernfs/inode.c:177 [inline]
kernfs_iop_permission+0x13f/0x220 fs/kernfs/inode.c:288
do_inode_permission fs/namei.c:462 [inline]
inode_permission+0x184/0x300 fs/namei.c:529
may_lookup fs/namei.c:1723 [inline]
link_path_walk+0x19e/0x7e0 fs/namei.c:2270
path_openat+0x1a0/0x1d40 fs/namei.c:3794
do_filp_open+0xf6/0x200 fs/namei.c:3825
do_sys_openat2+0xab/0x110 fs/open.c:1404
do_sys_open fs/open.c:1419 [inline]
__do_sys_openat fs/open.c:1435 [inline]
__se_sys_openat fs/open.c:1430 [inline]
__x64_sys_openat+0xf3/0x120 fs/open.c:1430
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+0x63/0x6b

value changed: 0x0000000065c7e790 -> 0x0000000065c7e791

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3270 Comm: udevd Not tainted 6.8.0-rc3-syzkaller-00279-g4a7bbe7519b6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

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