------------[ cut here ]------------
ODEBUG: free active (active state 0) object: ffff88807b800490 object type: timer_list hint: rose_t0timer_expiry+0x0/0x560 net/rose/rose_link.c:-1
WARNING: lib/debugobjects.c:615 at debug_print_object lib/debugobjects.c:612 [inline], CPU#0: syz.3.7998/7880
WARNING: lib/debugobjects.c:615 at __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline], CPU#0: syz.3.7998/7880
WARNING: lib/debugobjects.c:615 at debug_check_no_obj_freed+0x405/0x550 lib/debugobjects.c:1129, CPU#0: syz.3.7998/7880
Modules linked in:
CPU: 0 UID: 0 PID: 7880 Comm: syz.3.7998 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:debug_print_object lib/debugobjects.c:612 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:1099 [inline]
RIP: 0010:debug_check_no_obj_freed+0x44a/0x550 lib/debugobjects.c:1129
Code: 89 44 24 20 e8 b7 6b 7e fd 48 8b 44 24 20 4c 8b 4d 00 4c 89 ef 48 c7 c6 40 6b 27 8c 48 c7 c2 c0 70 27 8c 8b 0c 24 4d 89 f8 50 <67> 48 0f b9 3a 48 83 c4 08 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc
RSP: 0018:ffffc90000007b68 EFLAGS: 00010246
RAX: ffffffff8a888d00 RBX: ffffffff9a4985a8 RCX: 0000000000000000
RDX: ffffffff8c2770c0 RSI: ffffffff8c276b40 RDI: ffffffff901b4570
RBP: ffffffff8bcf4a00 R08: ffff88807b800490 R09: ffffffff8bcf5d20
R10: dffffc0000000000 R11: ffffffff81b099e0 R12: ffff88807b800600
R13: ffffffff901b4570 R14: ffff88807b800000 R15: ffff88807b800490
FS:  00007f4069bac6c0(0000) GS:ffff8881254b0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001038 CR3: 0000000036b02000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 slab_free_hook mm/slub.c:2601 [inline]
 slab_free mm/slub.c:6082 [inline]
 kfree+0x13a/0x610 mm/slub.c:6399
 rose_neigh_put include/net/rose.h:166 [inline]
 rose_timer_expiry+0x4cb/0x600 net/rose/rose_timer.c:183
 call_timer_fn+0x192/0x5a0 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
 run_timer_base kernel/time/timer.c:2394 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:skb_put+0x12a/0x210 net/core/skbuff.c:2656
Code: 00 00 00 45 8b 24 24 89 ef 44 89 e6 e8 6f ab 5c f8 44 39 e5 77 1f e8 a5 a9 5c f8 49 01 df 4c 89 f8 48 83 c4 10 5b 41 5c 41 5d <41> 5e 41 5f 5d c3 cc cc cc cc cc e8 86 a9 5c f8 4c 8b 7c 24 40 e8
RSP: 0018:ffffc9000efaf828 EFLAGS: 00000282
RAX: ffff88805ac1a0d6 RBX: ffff888057aecc18 RCX: 0000000000080000
RDX: ffffc9000c5e3000 RSI: 0000000000009d5c RDI: 0000000000009d5d
RBP: 000000000000005a R08: ffff88805ccc90a7 R09: 1ffff1100b999214
R10: dffffc0000000000 R11: ffffed100b999215 R12: 0000000000000056
R13: ffff888057aecb40 R14: ffff888057aecb40 R15: ffff88805ac1a0d6
 l2tp_ip_sendmsg+0x372/0x1620 net/l2tp/l2tp_ip.c:476
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x894/0xad0 net/socket.c:2592
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
 __sys_sendmmsg+0x27c/0x4e0 net/socket.c:2735
 __do_sys_sendmmsg net/socket.c:2762 [inline]
 __se_sys_sendmmsg net/socket.c:2759 [inline]
 __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2759
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4068d9c629
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:00007f4069bac028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f4069015fa0 RCX: 00007f4068d9c629
RDX: 00000000040000cf RSI: 0000200000000900 RDI: 0000000000000003
RBP: 00007f4068e32b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4069016038 R14: 00007f4069015fa0 R15: 00007fffdd4f0c78
 </TASK>
----------------
Code disassembly (best guess):
   0:	89 44 24 20          	mov    %eax,0x20(%rsp)
   4:	e8 b7 6b 7e fd       	call   0xfd7e6bc0
   9:	48 8b 44 24 20       	mov    0x20(%rsp),%rax
   e:	4c 8b 4d 00          	mov    0x0(%rbp),%r9
  12:	4c 89 ef             	mov    %r13,%rdi
  15:	48 c7 c6 40 6b 27 8c 	mov    $0xffffffff8c276b40,%rsi
  1c:	48 c7 c2 c0 70 27 8c 	mov    $0xffffffff8c2770c0,%rdx
  23:	8b 0c 24             	mov    (%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 18       	mov    0x18(%rsp),%r13
  38:	48                   	rex.W
  39:	b9 00 00 00 00       	mov    $0x0,%ecx
  3e:	00 fc                	add    %bh,%ah