[syzbot] [media?] WARNING: ODEBUG bug in cec_transmit_msg_fh

[syzbot <syzbot+051024d603432b4ab395@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    e21ee273e6fa Merge tag 'clk-fixes-for-linus' of git://git...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17340bd2580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4e828c596d7aa593
dashboard link: https://syzkaller.appspot.com/bug?extid=051024d603432b4ab395
compiler:       Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/14fcc3decf4c/disk-e21ee273.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3e80c98de356/vmlinux-e21ee273.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2a12732e35df/bzImage-e21ee273.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+051024d603432b4ab395@syzkaller.appspotmail.com

------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff888025d28cb8 object type: timer_list hint: cec_wait_timeout+0x0/0x180 include/media/cec.h:-1
WARNING: lib/debugobjects.c:632 at debug_print_object lib/debugobjects.c:629 [inline], CPU#1: syz.0.3204/21212
WARNING: lib/debugobjects.c:632 at __debug_check_no_obj_freed lib/debugobjects.c:1154 [inline], CPU#1: syz.0.3204/21212
WARNING: lib/debugobjects.c:632 at debug_check_no_obj_freed+0x358/0x530 lib/debugobjects.c:1184, CPU#1: syz.0.3204/21212
Modules linked in:
CPU: 1 UID: 0 PID: 21212 Comm: syz.0.3204 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:debug_print_object lib/debugobjects.c:629 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:1154 [inline]
RIP: 0010:debug_check_no_obj_freed+0x39c/0x530 lib/debugobjects.c:1184
Code: 48 89 04 24 e8 a5 b8 75 fd 48 8b 04 24 4c 8b 4d 00 4c 89 ef 48 c7 c6 e0 9f 28 8c 48 c7 c2 60 a5 28 8c 8b 4c 24 1c 4d 89 f8 50 <67> 48 0f b9 3a 48 83 c4 08 4c 8b 6c 24 10 48 b9 00 00 00 00 00 fc
RSP: 0018:ffffc90005ac78a0 EFLAGS: 00010246
RAX: ffffffff87e83c30 RBX: ffffffff9a6fa8b8 RCX: 0000000000000000
RDX: ffffffff8c28a560 RSI: ffffffff8c289fe0 RDI: ffffffff903a7340
RBP: ffffffff8bcf39c0 R08: ffff888025d28cb8 R09: ffffffff8bcf4d20
R10: dffffc0000000000 R11: ffffffff81b1a1f0 R12: 0000000000000001
R13: ffffffff903a7340 R14: ffff888025d28000 R15: ffff888025d28cb8
FS:  00007f6b13bf26c0(0000) GS:ffff8881253b9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa101deb078 CR3: 000000008a112000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 slab_free_hook mm/slub.c:2620 [inline]
 slab_free mm/slub.c:6251 [inline]
 kfree+0x13e/0x640 mm/slub.c:6566
 cec_transmit_msg_fh+0x16f0/0x24d0 drivers/media/cec/core/cec-adap.c:988
 cec_transmit drivers/media/cec/core/cec-api.c:230 [inline]
 cec_ioctl+0x2020/0x3060 drivers/media/cec/core/cec-api.c:534
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b1619ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6b13bf2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f6b16416360 RCX: 00007f6b1619ce59
RDX: 00002000000000c0 RSI: 00000000c0386105 RDI: 0000000000000006
RBP: 00007f6b16232d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b164163f8 R14: 00007f6b16416360 R15: 00007ffdafcf65c8
 </TASK>
----------------
Code disassembly (best guess):
   0:	48 89 04 24          	mov    %rax,(%rsp)
   4:	e8 a5 b8 75 fd       	call   0xfd75b8ae
   9:	48 8b 04 24          	mov    (%rsp),%rax
   d:	4c 8b 4d 00          	mov    0x0(%rbp),%r9
  11:	4c 89 ef             	mov    %r13,%rdi
  14:	48 c7 c6 e0 9f 28 8c 	mov    $0xffffffff8c289fe0,%rsi
  1b:	48 c7 c2 60 a5 28 8c 	mov    $0xffffffff8c28a560,%rdx
  22:	8b 4c 24 1c          	mov    0x1c(%rsp),%ecx
  26:	4d 89 f8             	mov    %r15,%r8
  29:	50                   	push   %rax
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	48 83 c4 08          	add    $0x8,%rsp
  33:	4c 8b 6c 24 10       	mov    0x10(%rsp),%r13
  38:	48                   	rex.W
  39:	b9 00 00 00 00       	mov    $0x0,%ecx
  3e:	00 fc                	add    %bh,%ah


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