[syzbot] [sound?] [usb?] WARNING: ODEBUG bug in snd_rawmidi_free

[syzbot <syzbot+d8f72178ab6783a7daea@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    2a239ffbebb5 Merge tag 'sound-6.15-rc5' of git://git.kerne..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15045b68580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a9a25b7a36123454
dashboard link: https://syzkaller.appspot.com/bug?extid=d8f72178ab6783a7daea
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15cfd8d4580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=126c1a70580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3398c42fd2ef/disk-2a239ffb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a3e276dc6661/vmlinux-2a239ffb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f0c67a315802/bzImage-2a239ffb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d8f72178ab6783a7daea@syzkaller.appspotmail.com

------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff888027cf0040 object type: timer_list hint: snd_usbmidi_error_timer+0x0/0x660 sound/usb/midi.c:2343
WARNING: CPU: 0 PID: 10 at lib/debugobjects.c:615 debug_print_object+0x16b/0x1e0 lib/debugobjects.c:612
Modules linked in:

CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.15.0-rc4-syzkaller-00291-g2a239ffbebb5 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: usb_hub_wq hub_event

RIP: 0010:debug_print_object+0x16b/0x1e0 lib/debugobjects.c:612
Code: 4c 89 ff e8 47 42 63 fd 4d 8b 0f 48 c7 c7 c0 db c1 8b 48 8b 34 24 4c 89 ea 89 e9 4d 89 f0 41 54 e8 aa a9 c5 fc 48 83 c4 08 90 <0f> 0b 90 90 ff 05 57 95 c0 0a 48 83 c4 08 5b 41 5c 41 5d 41 5e 41
RSP: 0018:ffffc900000f6990 EFLAGS: 00010296

RAX: 847b0a2dc845ef00 RBX: dffffc0000000000 RCX: ffff88801b681e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 0000000000000000 R08: ffffc900000f6667 R09: 1ffff9200001eccc
R10: dffffc0000000000 R11: fffff5200001eccd R12: ffffffff892410d0
R13: ffffffff8bc1dd40 R14: ffff888027cf0040 R15: ffffffff8b6cc2e0
FS:  0000000000000000(0000) GS:ffff8881260cb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff286001b8 CR3: 00000000316c4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline]
 debug_check_no_obj_freed+0x3a2/0x470 lib/debugobjects.c:1129
 slab_free_hook mm/slub.c:2311 [inline]
 slab_free mm/slub.c:4642 [inline]
 kfree+0x117/0x440 mm/slub.c:4841
 snd_rawmidi_free+0x3bc/0x410 sound/core/rawmidi.c:1934
 snd_rawmidi_dev_free+0x38/0x50 sound/core/rawmidi.c:1945
 __snd_device_free+0x1d2/0x2e0 sound/core/device.c:76
 snd_device_free_all+0xcf/0x180 sound/core/device.c:233
 snd_card_do_free sound/core/init.c:587 [inline]
 release_card_device+0x75/0x1b0 sound/core/init.c:153
 device_release+0x99/0x1c0 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+0x228/0x480 lib/kobject.c:737
 snd_card_free_when_closed sound/core/init.c:618 [inline]
 snd_card_free+0x110/0x190 sound/core/init.c:650
 usb_audio_probe+0x18ea/0x1dc0 sound/usb/card.c:940
 usb_probe_interface+0x641/0xbc0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x26a/0x9a0 drivers/base/dd.c:657
 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:829
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:957
 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b8/0x400 drivers/base/dd.c:1029
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3692
 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c1/0x390 drivers/usb/core/driver.c:291


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