[moderation] [fs?] WARNING: ODEBUG bug in fsnotify_mark_destroy_workfn

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c22e26bd0906 Merge tag 'landlock-7.0-rc1' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=139e295a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6428d17febdfb14e
dashboard link: https://syzkaller.appspot.com/bug?extid=fbbbb2d797e3a52782f0
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
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/b33c549157ca/disk-c22e26bd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/34c7ded19553/vmlinux-c22e26bd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/66faec2158ed/bzImage-c22e26bd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fbbbb2...@syzkaller.appspotmail.com

ODEBUG: object ffffc9000154f940 is on stack ffffc90001548000, but NOT annotated.
------------[ cut here ]------------
1
WARNING: lib/debugobjects.c:655 at debug_object_is_on_stack lib/debugobjects.c:655 [inline], CPU#1: kworker/u8:4/68
WARNING: lib/debugobjects.c:655 at lookup_object_or_alloc lib/debugobjects.c:688 [inline], CPU#1: kworker/u8:4/68
WARNING: lib/debugobjects.c:655 at debug_object_activate+0x424/0x520 lib/debugobjects.c:820, CPU#1: kworker/u8:4/68
Modules linked in:
CPU: 1 UID: 0 PID: 68 Comm: kworker/u8:4 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_unbound fsnotify_mark_destroy_workfn
RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:655 [inline]
RIP: 0010:lookup_object_or_alloc lib/debugobjects.c:688 [inline]
RIP: 0010:debug_object_activate+0x424/0x520 lib/debugobjects.c:820
Code: c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d e9 55 74 77 06 cc ff c5 89 2d cc 13 d0 14 48 c7 c7 80 1e 86 8b 48 89 de e8 7d bf 88 fc 90 <0f> 0b 90 49 81 fd 00 f0 ff ff 0f 86 a4 fd ff ff c7 44 24 04 00 00
RSP: 0018:ffffc9000154f8a0 EFLAGS: 00010046
RAX: 0000000000000050 RBX: ffffc9000154f940 RCX: d0ae81cde7617d00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff520002a9ec5 R12: ffff88801d76bc20
R13: ffff88813fe35000 R14: dffffc0000000000 R15: ffffffff8b2e28c0
FS: 0000000000000000(0000) GS:ffff888126695000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 000000003cdee000 CR4: 00000000003526f0
Call Trace:
<TASK>
debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
__call_srcu kernel/rcu/srcutree.c:1458 [inline]
__synchronize_srcu+0x2c9/0x3e0 kernel/rcu/srcutree.c:1517
fsnotify_mark_destroy_workfn+0x109/0x300 fs/notify/mark.c:996
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>


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