------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff888028ee8090 object type: timer_list hint: rose_t0timer_expiry+0x0/0x350 net/rose/rose_link.c:-1 WARNING: lib/debugobjects.c:615 at debug_print_object+0x16b/0x1e0 lib/debugobjects.c:612, CPU#1: syz.2.1147/9544 Modules linked in: CPU: 1 UID: 0 PID: 9544 Comm: syz.2.1147 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:debug_print_object+0x16b/0x1e0 lib/debugobjects.c:612 Code: 4c 89 ff e8 d7 19 86 fd 4d 8b 0f 48 c7 c7 80 1b e1 8b 48 8b 34 24 4c 89 ea 89 e9 4d 89 f0 41 54 e8 0a 38 e2 fc 48 83 c4 08 90 <0f> 0b 90 90 ff 05 47 22 1e 0b 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 RSP: 0018:ffffc90000a08a00 EFLAGS: 00010296 RAX: cfc2b002eab41900 RBX: dffffc0000000000 RCX: ffff888031311e80 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1c3a744 R12: ffffffff8a5327d0 R13: ffffffff8be11d00 R14: ffff888028ee8090 R15: ffffffff8b8cf8e0 FS: 00007fda22dbb6c0(0000) GS:ffff888125b82000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000000d000 CR3: 0000000078a42000 CR4: 00000000003526f0 Call Trace: __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:2470 [inline] slab_free mm/slub.c:6661 [inline] kfree+0x10c/0x6e0 mm/slub.c:6869 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4cb/0x600 net/rose/rose_timer.c:183 call_timer_fn+0x16e/0x600 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x27d/0x880 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1055 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1055 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_release+0x2ac/0x3d0 kernel/locking/lockdep.c:5893 Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 64 98 1b 11 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc90004e8f918 EFLAGS: 00000206 RAX: cfc2b002eab41900 RBX: 0000000000000283 RCX: cfc2b002eab41900 RDX: 0000000000000000 RSI: ffffffff8dc71e5c RDI: ffffffff8be111e0 RBP: ffff8880313129b0 R08: 0000000000000000 R09: ffffffff820eec00 R10: dffffc0000000000 R11: fffffbfff1f7eeef R12: 0000000000000000 R13: 0000000000000000 R14: ffff888034a18ca0 R15: ffff888031311e80 _inline_copy_from_user include/linux/uaccess.h:169 [inline] _copy_from_user+0x28/0xb0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:219 [inline] snd_rawmidi_kernel_write1+0x3ab/0x650 sound/core/rawmidi.c:1560 snd_rawmidi_write+0x5a8/0xbc0 sound/core/rawmidi.c:1629 do_loop_readv_writev fs/read_write.c:850 [inline] vfs_writev+0x4b6/0x960 fs/read_write.c:1059 do_writev+0x14d/0x2d0 fs/read_write.c:1103 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fda21f8f6c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fda22dbb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007fda221e5fa0 RCX: 00007fda21f8f6c9 RDX: 0000000000000002 RSI: 0000200000000840 RDI: 0000000000000004 RBP: 00007fda22011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fda221e6038 R14: 00007fda221e5fa0 R15: 00007ffd404da6b8 ---------------- Code disassembly (best guess): 0: 51 push %rcx 1: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) 8: 00 00 a: 9c pushf b: 8f 44 24 20 pop 0x20(%rsp) f: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp) 16: 00 17: 75 56 jne 0x6f 19: f7 c3 00 02 00 00 test $0x200,%ebx 1f: 74 01 je 0x22 21: fb sti 22: 65 48 8b 05 64 98 1b mov %gs:0x111b9864(%rip),%rax # 0x111b988e 29: 11 * 2a: 48 3b 44 24 28 cmp 0x28(%rsp),%rax <-- trapping instruction 2f: 0f 85 8b 00 00 00 jne 0xc0 35: 48 83 c4 30 add $0x30,%rsp 39: 5b pop %rbx 3a: 41 5c pop %r12 3c: 41 5d pop %r13 3e: 41 5e pop %r14