------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x11a/0x1d0 lib/refcount.c:28, CPU#1: kworker/1:3/5904 Modules linked in: CPU: 1 UID: 0 PID: 5904 Comm: kworker/1:3 Not tainted 6.16.0-next-20250731-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: md_misc mddev_delayed_delete RIP: 0010:refcount_warn_saturate+0x11a/0x1d0 lib/refcount.c:28 Code: e0 bb e2 8b e8 c7 06 bb fc 90 0f 0b 90 90 eb d7 e8 cb 6f f7 fc c6 05 78 cd c3 0a 01 90 48 c7 c7 40 bc e2 8b e8 a7 06 bb fc 90 <0f> 0b 90 90 eb b7 e8 ab 6f f7 fc c6 05 55 cd c3 0a 01 90 48 c7 c7 RSP: 0018:ffffc9000444fa68 EFLAGS: 00010246 RAX: 24ff285421d68b00 RBX: 0000000000000003 RCX: ffff88802ea90000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: ffffc9000444fc70 R08: ffff8880b8724253 R09: 1ffff110170e484a R10: dffffc0000000000 R11: ffffed10170e484b R12: ffff8880b87396c0 R13: ffff88805976c018 R14: ffff88807752c130 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888125d43000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2dc15ff8 CR3: 0000000052928000 CR4: 00000000003526f0 Call Trace: process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245