syzbot

FAT-fs (loop4): Can't find a valid FAT filesystem
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BUG: KCSAN: data-race in fsnotify_detach_mark / fsnotify_handle_inode_event

write to 0xffff888130a634a4 of 4 bytes by task 3300 on cpu 1:
 fsnotify_detach_mark+0xba/0x160 fs/notify/mark.c:554
 fsnotify_destroy_mark+0x70/0x150 fs/notify/mark.c:596
 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:805 [inline]
 __se_sys_inotify_rm_watch+0xe8/0x170 fs/notify/inotify/inotify_user.c:786
 __x64_sys_inotify_rm_watch+0x31/0x40 fs/notify/inotify/inotify_user.c:786
 x64_sys_call+0x2a15/0x3000 arch/x86/include/generated/asm/syscalls_64.h:256
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888130a634a4 of 4 bytes by task 8245 on cpu 0:
 fsnotify_handle_inode_event+0x125/0x220 fs/notify/fsnotify.c:313
 fsnotify_handle_event fs/notify/fsnotify.c:376 [inline]
 send_to_group fs/notify/fsnotify.c:424 [inline]
 fsnotify+0x13cf/0x14b0 fs/notify/fsnotify.c:641
 __fsnotify_parent+0x2ed/0x330 fs/notify/fsnotify.c:287
 fsnotify_parent include/linux/fsnotify.h:96 [inline]
 fsnotify_path include/linux/fsnotify.h:113 [inline]
 fsnotify_file include/linux/fsnotify.h:127 [inline]
 fsnotify_close include/linux/fsnotify.h:457 [inline]
 __fput+0x1de/0x650 fs/file_table.c:454
 fput_close_sync+0x6e/0x120 fs/file_table.c:573
 __do_sys_close fs/open.c:1589 [inline]
 __se_sys_close fs/open.c:1574 [inline]
 __x64_sys_close+0x56/0xf0 fs/open.c:1574
 x64_sys_call+0x2c25/0x3000 arch/x86/include/generated/asm/syscalls_64.h:4
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000003 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8245 Comm: +}[@ Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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