syzbot
WARNING: ODEBUG bug in vub300_disconnect
Status:
upstream: reported on 2026/08/25 01:37
Subsystems:
kernel
Labels:
prio:high
[Documentation on labels]
Reported-by: syzbot+f4a0159ce6802a0a4774@syzkaller.appspotmail.com
First crash: 12d, last: 1d07h
▶
▼
Last patch testing requests (1)
Sample crash report:
------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff8880330c1270 object type: timer_list hint: vub300_inactivity_timer_expired+0x0/0x3f0 include/linux/refcount.h:-1
WARNING: lib/debugobjects.c:632 at debug_print_object+0xec/0x230 lib/debugobjects.c:629, CPU#1: kworker/1:10/5891
Modules linked in:
CPU: 1 UID: 0 PID: 5891 Comm: kworker/1:10 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:debug_print_object+0x18a/0x230 lib/debugobjects.c:629
Code: f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 1d 91 4e fd 4d 8b 0f 4c 89 ef 48 8b 74 24 08 48 89 ea 44 89 e1 4d 89 f0 ff 34 24 <67> 48 0f b9 3a 48 83 c4 08 ff 05 d3 8d 91 0b 48 83 c4 10 5b 41 5c
RSP: 0018:ffffc9000530f218 EFLAGS: 00010246
RAX: 1ffffffff181f01c RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffffffff8c6d9040 RSI: ffffffff8c6d8ac0 RDI: ffffffff90854f90
RBP: ffffffff8c6d9040 R08: ffff8880330c1270 R09: ffffffff8c0f9440
R10: dffffc0000000000 R11: ffffffff81b3a0c0 R12: 0000000000000000
R13: ffffffff90854f90 R14: ffff8880330c1270 R15: ffffffff8c0f80e0
FS: 0000000000000000(0000) GS:ffff888124de0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6cd17f7fe0 CR3: 00000000335ba000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000063235cd5
DR3: 0000000000007000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__debug_check_no_obj_freed lib/debugobjects.c:1171 [inline]
debug_check_no_obj_freed+0x2e3/0x450 lib/debugobjects.c:1201
slab_free_hook mm/slub.c:2679 [inline]
slab_free mm/slub.c:6499 [inline]
kfree+0x13e/0x650 mm/slub.c:6792
device_release+0xc4/0x1f0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x222/0x550 lib/kobject.c:737
vub300_delete drivers/mmc/host/vub300.c:379 [inline]
kref_put include/linux/kref.h:65 [inline]
vub300_disconnect+0x280/0x2f0 drivers/mmc/host/vub300.c:2388
usb_unbind_interface+0x295/0x9f0 drivers/usb/core/driver.c:461
device_remove drivers/base/dd.c:618 [inline]
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x4f5/0x880 drivers/base/dd.c:1372
bus_remove_device+0x444/0x560 drivers/base/bus.c:664
device_del+0x524/0x8f0 drivers/base/core.c:3965
usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1478
usb_disconnect+0x346/0x9a0 drivers/usb/core/hub.c:2350
hub_port_connect drivers/usb/core/hub.c:5420 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
port_event drivers/usb/core/hub.c:5884 [inline]
hub_event+0x1bbb/0x4d30 drivers/usb/core/hub.c:5966
process_one_work kernel/workqueue.c:3387 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
----------------
Code disassembly (best guess):
0: f8 clc
1: 48 c1 e8 03 shr $0x3,%rax
5: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1)
9: 74 08 je 0x13
b: 4c 89 ff mov %r15,%rdi
e: e8 1d 91 4e fd call 0xfd4e9130
13: 4d 8b 0f mov (%r15),%r9
16: 4c 89 ef mov %r13,%rdi
19: 48 8b 74 24 08 mov 0x8(%rsp),%rsi
1e: 48 89 ea mov %rbp,%rdx
21: 44 89 e1 mov %r12d,%ecx
24: 4d 89 f0 mov %r14,%r8
27: ff 34 24 push (%rsp)
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 48 83 c4 08 add $0x8,%rsp
33: ff 05 d3 8d 91 0b incl 0xb918dd3(%rip) # 0xb918e0c
39: 48 83 c4 10 add $0x10,%rsp
3d: 5b pop %rbx
3e: 41 5c pop %r12
* Struck through repros no longer work on HEAD.