[moderation] [fs?] KCSAN: data-race in fsnotify_destroy_mark / inotify_handle_inode_event (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 20cb38a7af88 Merge tag 'for-6.9-rc2-tag' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12085225180000
kernel config: https://syzkaller.appspot.com/x/.config?x=ae557ecb5cabc4aa
dashboard link: https://syzkaller.appspot.com/bug?extid=72b0ce21c4170d6a277e
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [amir...@gmail.com ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1c92ddc37dc2/disk-20cb38a7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2f582de438c0/vmlinux-20cb38a7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c35d06026809/bzImage-20cb38a7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+72b0ce...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in fsnotify_destroy_mark / inotify_handle_inode_event

write to 0xffff88810ee0b594 of 4 bytes by task 21058 on cpu 1:
fsnotify_free_mark fs/notify/mark.c:481 [inline]
fsnotify_destroy_mark+0x146/0x1a0 fs/notify/mark.c:499
__do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:816 [inline]
__se_sys_inotify_rm_watch+0xfd/0x180 fs/notify/inotify/inotify_user.c:793
__x64_sys_inotify_rm_watch+0x31/0x40 fs/notify/inotify/inotify_user.c:793
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x72/0x7a

read to 0xffff88810ee0b594 of 4 bytes by task 16401 on cpu 0:
inotify_handle_inode_event+0x2c7/0x310 fs/notify/inotify/inotify_fsnotify.c:132
fsnotify_handle_inode_event+0x18e/0x1f0 fs/notify/fsnotify.c:270
fsnotify_handle_event fs/notify/fsnotify.c:322 [inline]
send_to_group fs/notify/fsnotify.c:370 [inline]
fsnotify+0x1023/0x1160 fs/notify/fsnotify.c:576
__fsnotify_parent+0x285/0x370 fs/notify/fsnotify.c:236
fsnotify_parent include/linux/fsnotify.h:83 [inline]
fsnotify_file include/linux/fsnotify.h:106 [inline]
fsnotify_close include/linux/fsnotify.h:387 [inline]
__fput+0x1ff/0x660 fs/file_table.c:408
__fput_sync+0x44/0x60 fs/file_table.c:507
__do_sys_close fs/open.c:1556 [inline]
__se_sys_close+0x101/0x1b0 fs/open.c:1541
__x64_sys_close+0x1f/0x30 fs/open.c:1541
do_syscall_64+0xd3/0x1d0
entry_SYSCALL_64_after_hwframe+0x72/0x7a

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 16401 Comm: syz-executor.0 Tainted: G W 6.9.0-rc3-syzkaller-00011-g20cb38a7af88 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================
EXT4-fs (loop0): unmounting filesystem 00000000-0000-0000-0000-000000000000.


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