WARNING: ODEBUG bug in vub300_disconnect

Status: upstream: reported on 2026/08/17 19:21
Reported-by: syzbot+15153703eae94c89f4f7@syzkaller.appspotmail.com
First crash: 21h26m, last: 21h26m

Sample crash report:
usb 2-1: USB disconnect, device number 9
------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: vub300_inactivity_timer_expired+0x0/0x3e0
WARNING: CPU: 1 PID: 4262 at lib/debugobjects.c:521 debug_print_object lib/debugobjects.c:518 [inline]
WARNING: CPU: 1 PID: 4262 at lib/debugobjects.c:521 __debug_check_no_obj_freed lib/debugobjects.c:990 [inline]
WARNING: CPU: 1 PID: 4262 at lib/debugobjects.c:521 debug_check_no_obj_freed+0x395/0x520 lib/debugobjects.c:1020
Modules linked in:
CPU: 1 PID: 4262 Comm: kworker/1:8 Not tainted syzkaller #0
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 lib/debugobjects.c:518 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:990 [inline]
RIP: 0010:debug_check_no_obj_freed+0x395/0x520 lib/debugobjects.c:1020
Code: e8 b0 41 d1 fd 4c 8b 45 00 48 c7 c7 20 4b 7a 8a 48 c7 c6 e0 47 7a 8a 48 c7 c2 80 4c 7a 8a 8b 4c 24 1c 4d 89 e9 e8 eb 4b c8 05 <0f> 0b 4c 8b 6c 24 10 48 b9 00 00 00 00 00 fc ff df ff 05 ac 63 9e
RSP: 0018:ffffc9000368f448 EFLAGS: 00010246

RAX: 686a8a67905bfb00 RBX: ffffffff964de3e8 RCX: 0000000000100000
RDX: ffffc90017035000 RSI: 0000000000014271 RDI: 0000000000014272
RBP: ffffffff8a2cacc0 R08: ffff8880b9133d7f R09: 1ffff110172267af
R10: dffffc0000000000 R11: ffffed10172267b0 R12: 0000000000000001
R13: ffffffff872d9fc0 R14: ffff888053981000 R15: ffff888053981280
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2adadf82f8 CR3: 0000000074881000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 slab_free_hook mm/slub.c:1685 [inline]
 slab_free_freelist_hook+0x8b/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 device_release+0x92/0x1c0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:713 [inline]
 kobject_release lib/kobject.c:744 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x217/0x450 lib/kobject.c:761
 vub300_delete drivers/mmc/host/vub300.c:378 [inline]
 kref_put include/linux/kref.h:65 [inline]
 vub300_disconnect+0x277/0x2e0 drivers/mmc/host/vub300.c:2383
 usb_unbind_interface+0x203/0x870 drivers/usb/core/driver.c:458
 __device_release_driver drivers/base/dd.c:1249 [inline]
 device_release_driver_internal+0x487/0x710 drivers/base/dd.c:1282
 bus_remove_device+0x2dd/0x400 drivers/base/bus.c:531
 device_del+0x63f/0xa80 drivers/base/core.c:3615

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/17 19:20 linux-5.15.y aabd761612db 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: ODEBUG bug in vub300_disconnect
* Struck through repros no longer work on HEAD.