syzbot


WARNING: refcount bug in process_scheduled_works

Status: upstream: reported C repro on 2025/07/29 21:58
Subsystems: fuse
[Documentation on labels]
Reported-by: syzbot+9921e319bd6168140b40@syzkaller.appspotmail.com
First crash: 4d12h, last: 10h15m
Cause bisection: introduced by (bisect log) :
commit 9e59d609763f70a992a8f3808dabcce60f14eb5c
Author: Xiao Ni <xni@redhat.com>
Date: Wed Jun 11 07:31:06 2025 +0000

  md: call del_gendisk in control path

Crash: WARNING: refcount bug in process_scheduled_works (log)
Repro: C syz .config
  
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] md: fix create on open mddev lifetime regression 4 (4) 2025/07/30 18:20
[syzbot] [fuse?] WARNING: refcount bug in process_scheduled_works 3 (7) 2025/07/30 10:26
Last patch testing requests (3)
Created Duration User Patch Repo Result
2025/07/30 08:36 34m hdanton@sina.com patch upstream OK log
2025/07/30 08:24 16m hdanton@sina.com patch upstream report log
2025/07/30 02:03 1h25m hdanton@sina.com patch upstream report log

Sample crash report:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 24 at lib/refcount.c:28 refcount_warn_saturate+0x11a/0x1d0 lib/refcount.c:28
Modules linked in:
CPU: 1 UID: 0 PID: 24 Comm: kworker/1:0 Not tainted 6.16.0-syzkaller-00857-gced1b9e0392d #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: 00 83 e2 8b e8 b7 5b bf fc 90 0f 0b 90 90 eb d7 e8 bb 6d fb fc c6 05 09 32 c7 0a 01 90 48 c7 c7 60 83 e2 8b e8 97 5b bf fc 90 <0f> 0b 90 90 eb b7 e8 9b 6d fb fc c6 05 e6 31 c7 0a 01 90 48 c7 c7
RSP: 0018:ffffc900001e7a68 EFLAGS: 00010246
RAX: 4efff925454ad500 RBX: 0000000000000003 RCX: ffff88801d2b8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc900001e7c70 R08: ffff8880b8724293 R09: 1ffff110170e4852
R10: dffffc0000000000 R11: ffffed10170e4853 R12: ffff8880b8739700
R13: ffff88801ce88e18 R14: ffff8880340f6130 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125d07000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe95c20b278 CR3: 000000000df38000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (82):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/29 13:15 upstream ced1b9e0392d c4a95487 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 10:57 upstream ced1b9e0392d c4a95487 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 08:39 upstream ced1b9e0392d c4a95487 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/08/01 16:56 upstream 89748acdf226 40127d41 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/08/01 06:27 upstream f2d282e1dfb3 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/08/01 01:15 upstream 260f6f4fda93 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 10:17 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 03:27 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 03:27 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 02:55 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 02:53 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 02:53 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 02:53 upstream e8d780dcd957 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/30 06:58 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/30 04:51 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/30 04:51 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/30 04:50 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/30 04:44 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 23:23 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 23:22 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 23:22 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 23:20 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 21:42 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 21:42 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 21:41 upstream 86aa72182095 f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 05:43 upstream ced1b9e0392d c4a95487 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 05:42 upstream ced1b9e0392d c4a95487 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 05:38 upstream ced1b9e0392d c4a95487 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 05:38 upstream ced1b9e0392d c4a95487 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/29 05:01 upstream ced1b9e0392d c4a95487 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/08/02 06:50 linux-next 84b92a499e7e 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/08/02 06:48 linux-next 84b92a499e7e 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/08/01 20:07 linux-next 84b92a499e7e 40127d41 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/08/01 18:14 linux-next 84b92a499e7e 40127d41 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/08/01 11:33 linux-next 84b92a499e7e 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 13:39 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 12:29 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING: refcount bug in process_scheduled_works
2025/07/31 06:16 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 06:16 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 06:16 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 06:16 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 06:09 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 06:08 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 06:07 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 06:07 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 05:57 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 05:56 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
2025/07/31 05:56 linux-next 84b92a499e7e f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING: refcount bug in process_scheduled_works
* Struck through repros no longer work on HEAD.