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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6c0483dbfe72 Merge tag 'nfsd-6.10-3' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=128ae7a6980000
kernel config: https://syzkaller.appspot.com/x/.config?x=7e87b541dc1fc960
dashboard link: https://syzkaller.appspot.com/bug?extid=43f02eff7fe42b98048a
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/de863bb23b68/disk-6c0483db.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/603ef91ee71e/vmlinux-6c0483db.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7991a5125386/bzImage-6c0483db.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+43f02e...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in fsnotify / fsnotify_put_mark

write to 0xffff8881001c9474 of 4 bytes by task 3310 on cpu 1:
fsnotify_detach_connector_from_object fs/notify/mark.c:304 [inline]
fsnotify_put_mark+0x2d8/0x5d0 fs/notify/mark.c:367
__do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:819 [inline]
__se_sys_inotify_rm_watch+0x105/0x180 fs/notify/inotify/inotify_user.c:793
__x64_sys_inotify_rm_watch+0x31/0x40 fs/notify/inotify/inotify_user.c:793
x64_sys_call+0x1b06/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:256
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

read to 0xffff8881001c9474 of 4 bytes by task 3093 on cpu 0:
fsnotify+0x36c/0x11a0 fs/notify/fsnotify.c:553
__fsnotify_parent+0x285/0x370 fs/notify/fsnotify.c:250
fsnotify_parent include/linux/fsnotify.h:96 [inline]
fsnotify_file include/linux/fsnotify.h:125 [inline]
fsnotify_close include/linux/fsnotify.h:406 [inline]
__fput+0x1f7/0x660 fs/file_table.c:408
__fput_sync+0x44/0x60 fs/file_table.c:507
__do_sys_close fs/open.c:1555 [inline]
__se_sys_close+0x101/0x1b0 fs/open.c:1540
__x64_sys_close+0x1f/0x30 fs/open.c:1540
x64_sys_call+0x25f1/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:4
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: 0x00002008 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3093 Comm: syz-executor Not tainted 6.10.0-rc5-syzkaller-00243-g6c0483dbfe72 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================


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