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: 21d, last: 2d02h
▶
▼
Last patch testing requests (1)
Sample crash report:
------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff888033c81270 object type: timer_list hint: vub300_inactivity_timer_expired+0x0/0x550 drivers/mmc/host/vub300.c:1447
WARNING: lib/debugobjects.c:629 at debug_print_object+0x198/0x2b0 lib/debugobjects.c:629, CPU#1: kworker/1:1/31
Modules linked in:
CPU: 1 UID: 0 PID: 31 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:debug_print_object+0x1a5/0x2b0 lib/debugobjects.c:629
Code: b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 48 8d 3d 78 19 1c 0c 41 56 48 8b 14 ed 40 20 62 8c 4c 89 e6 <67> 48 0f b9 3a 58 83 05 22 77 11 0c 01 48 83 c4 18 5b 5d 41 5c 41
RSP: 0018:ffffc90000a773c8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffffc90000a774b0 RCX: 0000000000000000
RDX: ffffffff8c621f80 RSI: ffffffff8c621b20 RDI: ffffffff914fd650
RBP: 0000000000000003 R08: ffff888033c81270 R09: ffffffff8bf30fc0
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8c621b20
R13: ffffffff8bf31000 R14: ffffffff88c8ce70 R15: ffffc90000a774c8
FS: 0000000000000000(0000) GS:ffff888123c60000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000054c0 CR3: 000000005d5c1000 CR4: 00000000003526f0
Call Trace:
<TASK>
__debug_check_no_obj_freed lib/debugobjects.c:1171 [inline]
debug_check_no_obj_freed+0x4da/0x630 lib/debugobjects.c:1201
slab_free_hook mm/slub.c:2679 [inline]
slab_free mm/slub.c:6499 [inline]
kfree+0x3d6/0x6d0 mm/slub.c:6792
device_release+0xd2/0x270 drivers/base/core.c:2640
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1f7/0x640 lib/kobject.c:737
put_device+0x1f/0x30 drivers/base/core.c:3884
vub300_delete drivers/mmc/host/vub300.c:379 [inline]
kref_put.constprop.0.isra.0+0x159/0x1d0 include/linux/kref.h:65
vub300_disconnect+0x136/0x170 drivers/mmc/host/vub300.c:2388
usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:461
device_remove drivers/base/dd.c:618 [inline]
device_remove+0x12a/0x180 drivers/base/dd.c:610
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
device_del+0x376/0x9b0 drivers/base/core.c:3965
usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
usb_disconnect+0x2e2/0x9a0 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+0x1bb1/0x4420 drivers/usb/core/hub.c:5966
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 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: b8 00 00 00 00 mov $0x0,%eax
5: 00 fc add %bh,%ah
7: ff lcall (bad)
8: df 48 89 fisttps -0x77(%rax)
b: fa cli
c: 48 c1 ea 03 shr $0x3,%rdx
10: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
14: 75 4f jne 0x65
16: 48 8d 3d 78 19 1c 0c lea 0xc1c1978(%rip),%rdi # 0xc1c1995
1d: 41 56 push %r14
1f: 48 8b 14 ed 40 20 62 mov -0x739ddfc0(,%rbp,8),%rdx
26: 8c
27: 4c 89 e6 mov %r12,%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 58 pop %rax
30: 83 05 22 77 11 0c 01 addl $0x1,0xc117722(%rip) # 0xc117759
37: 48 83 c4 18 add $0x18,%rsp
3b: 5b pop %rbx
3c: 5d pop %rbp
3d: 41 5c pop %r12
3f: 41 rex.B
* Struck through repros no longer work on HEAD.