[v5.15] WARNING: ODEBUG bug in snd_rawmidi_free

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cc5ec8769306 Linux 5.15.196
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17bdafe2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=0d3945394228cf36bcd6
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=127fae14580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15ed5704580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c71c660545b2/disk-cc5ec876.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4f011826cca6/vmlinux-cc5ec876.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8ccd1a2c3f8c/bzImage-cc5ec876.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0d3945...@syzkaller.appspotmail.com

------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: snd_usbmidi_error_timer+0x0/0x660
WARNING: CPU: 0 PID: 1325 at lib/debugobjects.c:521 debug_print_object lib/debugobjects.c:518 [inline]
WARNING: CPU: 0 PID: 1325 at lib/debugobjects.c:521 __debug_check_no_obj_freed lib/debugobjects.c:973 [inline]
WARNING: CPU: 0 PID: 1325 at lib/debugobjects.c:521 debug_check_no_obj_freed+0x43c/0x530 lib/debugobjects.c:1003
Modules linked in:
CPU: 0 PID: 1325 Comm: kworker/0:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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:973 [inline]
RIP: 0010:debug_check_no_obj_freed+0x43c/0x530 lib/debugobjects.c:1003
Code: ef e8 f8 f1 dc fd 4c 8b 45 00 48 c7 c7 a0 ee 59 8a 48 c7 c6 60 eb 59 8a 48 c7 c2 00 f0 59 8a 8b 0c 24 4d 89 e9 e8 94 65 bf 05 <0f> 0b 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc ff df ff 05 75 8e 8a
RSP: 0018:ffffc90005076a18 EFLAGS: 00010246

RAX: 05d13cdd3c670d00 RBX: ffffffff96286de8 RCX: ffff88802208bb80
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffffff8a0c9d40 R08: dffffc0000000000 R09: ffffed10172067b0
R10: ffffed10172067b0 R11: 1ffff110172067af R12: ffff888075076400
R13: ffffffff87c3d730 R14: ffff888075076000 R15: ffff888075076040
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30d63fff CR3: 000000001d4d0000 CR4: 00000000003506f0
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
snd_rawmidi_free+0x3b7/0x3e0 sound/core/rawmidi.c:1844
snd_rawmidi_dev_free+0x34/0x40 sound/core/rawmidi.c:1853
__snd_device_free+0x1cd/0x2e0 sound/core/device.c:76
snd_device_free_all+0xcb/0x180 sound/core/device.c:233
snd_card_do_free sound/core/init.c:588 [inline]
release_card_device+0x6d/0x1f0 sound/core/init.c:145
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+0x21d/0x460 lib/kobject.c:761
snd_card_free_when_closed sound/core/init.c:620 [inline]
snd_card_free+0x123/0x190 sound/core/init.c:653
usb_audio_probe+0x187f/0x1d50 sound/usb/card.c:939
usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979


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