[v5.15] WARNING: ODEBUG bug in vub300_disconnect

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aabd761612db Linux 5.15.215
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13b13949580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f161cbc9aef65db0
dashboard link: https://syzkaller.appspot.com/bug?extid=15153703eae94c89f4f7
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f636f56d3662/disk-aabd7616.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f1a46620f40c/vmlinux-aabd7616.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9b78bb48b022/bzImage-aabd7616.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+151537...@syzkaller.appspotmail.com

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


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