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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 22f902dfc51e Merge tag 'i2c-for-6.10-rc7' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=174edd69980000
kernel config: https://syzkaller.appspot.com/x/.config?x=5b9537cd00be479e
dashboard link: https://syzkaller.appspot.com/bug?extid=876352de1b1faa223a9f
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/aaf5ae033f17/disk-22f902df.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/14e4f4a3e0c2/vmlinux-22f902df.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d37ca0d5a872/bzImage-22f902df.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+876352...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in fsnotify_detach_mark / fsnotify_handle_inode_event

write to 0xffff888104484134 of 4 bytes by task 3807 on cpu 0:
fsnotify_detach_mark+0xe1/0x190 fs/notify/mark.c:511
fsnotify_destroy_mark+0x9a/0x1a0 fs/notify/mark.c:553
__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
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 0xffff888104484134 of 4 bytes by task 4864 on cpu 1:
fsnotify_handle_inode_event+0xf6/0x1f0 fs/notify/fsnotify.c:276
fsnotify_handle_event fs/notify/fsnotify.c:336 [inline]
send_to_group fs/notify/fsnotify.c:384 [inline]
fsnotify+0x10ba/0x11a0 fs/notify/fsnotify.c:593
__fsnotify_parent+0x285/0x370 fs/notify/fsnotify.c:250
fsnotify_parent include/linux/fsnotify.h:96 [inline]
fsnotify_file include/linux/fsnotify.h:131 [inline]
fsnotify_close include/linux/fsnotify.h:412 [inline]
__fput+0x5ca/0x6f0 fs/file_table.c:408
__fput_sync+0x44/0x60 fs/file_table.c:507
__do_sys_close fs/open.c:1563 [inline]
__se_sys_close+0x101/0x1b0 fs/open.c:1548
__x64_sys_close+0x1f/0x30 fs/open.c:1548
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: 0x00000003 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4864 Comm: syz-executor Not tainted 6.10.0-rc6-syzkaller-00215-g22f902dfc51e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================


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