KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event (2)

Status: moderation: reported on 2024/10/13 04:50
Subsystems: fs
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+b843bae81ed3042a49b9@syzkaller.appspotmail.com
First crash: 659d, last: 5d14h
✨ AI Jobs (4)
ID Workflow Result Correct Bug Created Started Finished Revision Error
5a6c3993 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event (2) 2026/05/15 11:16 2026/05/15 11:34 2026/05/15 11:41 9cd3beaa

			
		
81e3d0ed repro KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event (2) 2026/03/07 13:56 2026/03/07 13:56 2026/03/07 13:57 31e9c887

			
		
d0251fcc assessment-kcsan Benign: ✅ Confident: ✅ KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event (2) 2026/02/24 19:38 2026/02/24 19:38 2026/02/24 19:41 305c0ec5

			
		
9534f3dc assessment-kcsan 💥 KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event (2) 2026/01/10 01:37 2026/01/10 01:37 2026/01/10 01:37 75199160
Error 429, Message: You exceeded your current quota, please check your plan and billing details. For more information on this error, head to: https://ai.google.dev/gemini-api/docs/rate-limits. To moni...
truncated to first 200 bytes; open job for full error
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event fs 6 242 705d 969d 0/29 auto-obsoleted due to no activity on 2024/10/01 14:35

Sample crash report:
loop0: detected capacity change from 0 to 512
EXT4-fs (loop0): can't mount with commit=, fs mounted w/o journal
loop0: detected capacity change from 0 to 128
==================================================================
BUG: KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event

write to 0xffff8881049cf904 of 4 bytes by task 3285 on cpu 1:
 fsnotify_detach_mark+0xb9/0x160 fs/notify/mark.c:624
 fsnotify_destroy_mark+0x6a/0x140 fs/notify/mark.c:666
 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:806 [inline]
 __se_sys_inotify_rm_watch+0xe8/0x170 fs/notify/inotify/inotify_user.c:787
 __x64_sys_inotify_rm_watch+0x31/0x40 fs/notify/inotify/inotify_user.c:787
 x64_sys_call+0xc88/0x3020 arch/x86/include/generated/asm/syscalls_64.h:256
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881049cf904 of 4 bytes by task 5291 on cpu 0:
 inotify_handle_inode_event+0x34c/0x3c0 fs/notify/inotify/inotify_fsnotify.c:132
 fsnotify_handle_inode_event+0x1d3/0x230 fs/notify/fsnotify.c:275
 fsnotify_handle_event fs/notify/fsnotify.c:330 [inline]
 send_to_group fs/notify/fsnotify.c:378 [inline]
 fsnotify+0x16ae/0x1860 fs/notify/fsnotify.c:597
 __fsnotify_parent+0x2f8/0x3a0 fs/notify/fsnotify.c:241
 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:461 [inline]
 __fput+0x1e2/0x630 fs/file_table.c:498
 fput_close_sync+0xad/0x190 fs/file_table.c:617
 __do_sys_close fs/open.c:1511 [inline]
 __se_sys_close fs/open.c:1496 [inline]
 __x64_sys_close+0x55/0xf0 fs/open.c:1496
 x64_sys_call+0x275d/0x3020 arch/x86/include/generated/asm/syscalls_64.h:4
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 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: 5291 Comm: syz.0.516 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
==================================================================
EXT4-fs (loop0): mounted filesystem 76b65be2-f6da-4727-8c75-0525a5b65a09 r/w without journal. Quota mode: none.
ext4 filesystem being mounted at /97/file0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa supports timestamps until 2038-01-19 (0x7fffffff)

Crashes (81):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/28 18:59 upstream 3b5f4b83c4ab edc8a875 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/07/22 04:18 upstream 248951ddc14d b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/07/14 14:22 upstream 3b029c035b34 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/07/12 17:49 upstream 44696aa3a489 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/07/01 21:27 upstream 665159e24674 27192279 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/06/08 07:02 upstream 4549871118cf cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/06/06 12:53 upstream c10130c234c8 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/05/29 11:50 upstream 8fde5d1d47f6 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/05/27 10:56 upstream eb3f4b7426cf 8777bdc3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/04/16 01:23 upstream aec2f682d47c df15c5f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/04/01 06:37 upstream dbf00d8d23b4 fb8b2c26 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/03/30 15:37 upstream 7aaa8047eafd dcaebc52 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/03/26 22:23 upstream 0138af2472df 766b6434 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/03/12 02:14 upstream b29fb8829bff 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/03/06 03:17 upstream 5ee8dbf54602 31e9c887 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/03/05 22:27 upstream c107785c7e8d d20b04c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/03/01 02:57 upstream 2f9339c052bd 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/02/28 11:20 upstream 4d349ee5c778 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/02/25 00:25 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/02/22 07:48 upstream fa5c82f4d2bb 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/02/19 21:57 upstream 2b7a25df823d c8d8c52d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/02/17 22:21 upstream d295082ea672 06ec4f7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/01/25 07:37 upstream 5dbeeb268b63 40acda8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/01/24 03:54 upstream 5bde837031a3 4f25b9b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2026/01/04 14:28 upstream aacb0a6d604a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/12/21 13:36 upstream 9094662f6707 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/12/17 04:17 upstream 40fbbd64bba6 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/12/13 04:46 upstream 9551a26f17d9 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/12/06 06:16 upstream d1d36025a617 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/11/30 09:05 upstream 6bda50f4333f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/11/24 19:31 upstream ac3fd01e4c1e bf6fe8fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/11/24 03:54 upstream d0e88704d96c 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/11/19 10:33 upstream 8b690556d8fe 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/11/19 00:24 upstream 5bebe8de1926 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/11/10 21:57 upstream 4ea7c1717f3f 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/11/06 23:17 upstream c2c2ccfd4ba7 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/10/30 20:55 upstream e53642b87a4f 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/10/30 05:25 upstream e53642b87a4f fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/10/23 15:41 upstream 43e9ad0c55a3 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/10/16 22:48 upstream 98ac9cc4b445 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/09/29 05:27 upstream 8f9736633f8c 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/09/03 03:15 upstream e6b9dce0aeeb 96a211bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/08/25 03:14 upstream 69fd6b99b8f8 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/08/22 15:31 upstream 3957a5720157 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/08/19 05:48 upstream be48bcf004f9 523f460e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/08/11 02:55 upstream 8f5ae30d69d7 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/01/18 18:23 upstream 595523945be0 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/01/11 09:51 upstream 77a903cd8e5a 6dbc6a9b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2025/01/06 15:34 upstream 9d89551994a4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/12/29 23:46 upstream 4099a71718b0 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/12/23 06:18 upstream bcde95ce32b6 b4fbdbd4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/12/20 20:42 upstream e9b8ffafd20a 0f61b415 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/12/12 09:10 upstream 231825b2e1ff 6f1b0fa8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/12/07 00:11 upstream 9a6e8c7c3a02 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/11/26 05:34 upstream 2c22dc1ee3a1 11dbc254 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/11/16 14:42 upstream e8bdb3c8be08 cfe3a04a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/11/03 19:27 upstream a33ab3f94f51 f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/10/22 16:45 upstream d12937763990 a93682b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/10/20 17:46 upstream 715ca9dd687f cd6fc0a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/10/16 14:19 upstream 2f87d0916ce0 bde2d81c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
2024/10/13 04:49 upstream 7234e2ea0edd 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in fsnotify_detach_mark / inotify_handle_inode_event
* Struck through repros no longer work on HEAD.