syzbot


WARNING in fanotify_handle_event

Status: upstream: reported C repro on 2025/07/08 10:20
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+a0cd7865c5b095e95d01@syzkaller.appspotmail.com
First crash: 7d14h, last: 7d12h
Bug presence (1)
Date Name Commit Repro Result
2025/07/13 upstream (ToT) 3f31a806a62e C [report] WARNING in fanotify_handle_event
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in fanotify_handle_event (2) exfat -1 C 14 7d14h 245d 0/29 upstream: reported C repro on 2024/11/12 04:21
linux-5.15 WARNING in fanotify_handle_event origin:upstream -1 C 4 7d13h 7d15h 0/3 upstream: reported C repro on 2025/07/08 09:14
upstream WARNING in fanotify_handle_event fs -1 C done 5 2220d 2219d 12/29 fixed on 2019/07/10 21:40

Sample crash report:
loop0: detected capacity change from 0 to 128
process 'syz.0.16' launched './file0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4432 at fs/notify/fanotify/fanotify.h:216 fanotify_info_copy_name fs/notify/fanotify/fanotify.h:216 [inline]
WARNING: CPU: 0 PID: 4432 at fs/notify/fanotify/fanotify.h:216 fanotify_alloc_name_event fs/notify/fanotify/fanotify.c:646 [inline]
WARNING: CPU: 0 PID: 4432 at fs/notify/fanotify/fanotify.h:216 fanotify_alloc_event fs/notify/fanotify/fanotify.c:810 [inline]
WARNING: CPU: 0 PID: 4432 at fs/notify/fanotify/fanotify.h:216 fanotify_handle_event+0x237d/0x36a0 fs/notify/fanotify/fanotify.c:948
Modules linked in:
CPU: 0 PID: 4432 Comm: syz.0.16 Not tainted 6.1.143-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:fanotify_info_copy_name fs/notify/fanotify/fanotify.h:216 [inline]
RIP: 0010:fanotify_alloc_name_event fs/notify/fanotify/fanotify.c:646 [inline]
RIP: 0010:fanotify_alloc_event fs/notify/fanotify/fanotify.c:810 [inline]
RIP: 0010:fanotify_handle_event+0x237d/0x36a0 fs/notify/fanotify/fanotify.c:948
Code: ae dd ff ff e8 24 5e 8e ff 0f 0b eb 79 e8 1b 5e 8e ff 0f 0b e9 b2 fa ff ff e8 0f 5e 8e ff 0f 0b e9 e6 fb ff ff e8 03 5e 8e ff <0f> 0b e9 47 fd ff ff e8 f7 5d 8e ff 0f 0b e9 cd fe ff ff e8 eb 5d
RSP: 0018:ffffc90003497780 EFLAGS: 00010293
RAX: ffffffff81f2797d RBX: 0000000000000ffd RCX: ffff88807a775940
RDX: 0000000000000000 RSI: 0000000000000ffd RDI: 00000000000000ff
RBP: ffffc90003497960 R08: ffff88807a775940 R09: 0000000000000002
R10: 00000000000000ff R11: 0000000000000000 R12: ffff888073640000
R13: ffff888073640000 R14: dffffc0000000000 R15: 0000000000000000
FS:  000055557a732500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001400 CR3: 0000000023e5c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 send_to_group fs/notify/fsnotify.c:374 [inline]
 fsnotify+0x10ee/0x1cc0 fs/notify/fsnotify.c:584
 __fsnotify_parent+0x5ae/0x6e0 fs/notify/fsnotify.c:241
 fsnotify_parent include/linux/fsnotify.h:77 [inline]
 fsnotify_file include/linux/fsnotify.h:105 [inline]
 fsnotify_open include/linux/fsnotify.h:336 [inline]
 do_open_execat+0x5d1/0x730 fs/exec.c:945
 bprm_execve+0x55c/0x18a0 fs/exec.c:1849
 do_execveat_common+0x51b/0x6c0 fs/exec.c:1979
 do_execve fs/exec.c:2053 [inline]
 __do_sys_execve fs/exec.c:2129 [inline]
 __se_sys_execve fs/exec.c:2124 [inline]
 __x64_sys_execve+0x8e/0xa0 fs/exec.c:2124
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efe1eb8e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe36202148 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00007efe1edb5fa0 RCX: 00007efe1eb8e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000440
RBP: 00007efe1ec10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efe1edb5fa0 R14: 00007efe1edb5fa0 R15: 0000000000000003
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/08 12:05 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in fanotify_handle_event
2025/07/08 11:32 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in fanotify_handle_event
2025/07/08 10:57 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in fanotify_handle_event
2025/07/08 10:20 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in fanotify_handle_event
2025/07/08 10:19 linux-6.1.y 04d1ccaa9c28 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in fanotify_handle_event
* Struck through repros no longer work on HEAD.