GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog ------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff88804f719890 object type: timer_list hint: rose_t0timer_expiry+0x0/0x560 net/rose/rose_link.c:-1 WARNING: lib/debugobjects.c:632 at debug_print_object lib/debugobjects.c:629 [inline], CPU#0: syz.0.3594/20999 WARNING: lib/debugobjects.c:632 at __debug_check_no_obj_freed lib/debugobjects.c:1116 [inline], CPU#0: syz.0.3594/20999 WARNING: lib/debugobjects.c:632 at debug_check_no_obj_freed+0x405/0x550 lib/debugobjects.c:1146, CPU#0: syz.0.3594/20999 Modules linked in: CPU: 0 UID: 0 PID: 20999 Comm: syz.0.3594 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:debug_print_object lib/debugobjects.c:629 [inline] RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:1116 [inline] RIP: 0010:debug_check_no_obj_freed+0x44a/0x550 lib/debugobjects.c:1146 Code: 89 44 24 20 e8 f7 bf 74 fd 48 8b 44 24 20 4c 8b 4d 00 4c 89 ef 48 c7 c6 a0 a5 28 8c 48 c7 c2 20 ab 28 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:ffffc90000007b48 EFLAGS: 00010246 RAX: ffffffff8a9f6db0 RBX: ffffffff9a794380 RCX: 0000000000000000 RDX: ffffffff8c28ab20 RSI: ffffffff8c28a5a0 RDI: ffffffff903e6a40 RBP: ffffffff8bcf39a0 R08: ffff88804f719890 R09: ffffffff8bcf4d00 R10: dffffc0000000000 R11: ffffffff81b236d0 R12: ffff88804f719a00 R13: ffffffff903e6a40 R14: ffff88804f719000 R15: ffff88804f719890 FS: 00007f0c550c06c0(0000) GS:ffff888125213000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff3dd7d10a0 CR3: 000000003962a000 CR4: 00000000003526f0 Call Trace: slab_free_hook mm/slub.c:2620 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x13e/0x640 mm/slub.c:6561 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4cb/0x600 net/rose/rose_timer.c:183 call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x30/0x90 kernel/kcov.c:321 Code: 04 24 65 48 8b 0d 28 fa 7a 11 65 8b 15 49 fa 7a 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 cc 16 00 00 00 74 4e <8b> 91 a8 16 00 00 83 fa 03 75 43 48 8b 91 b0 16 00 00 44 8b 89 ac RSP: 0018:ffffc90005cef518 EFLAGS: 00000246 RAX: ffffffff8bb6989c RBX: 0000000000000002 RCX: ffff8880ab860000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000002 RBP: 0000000000000006 R08: ffffc90005cef6ff R09: 0000000000000000 R10: ffffc90005cef6e8 R11: fffff52000b9dee0 R12: ffffc90005cef6c8 R13: ffff8880ae8002c2 R14: ffff8880ae8002c2 R15: dffffc0000000000 xa_is_internal include/linux/xarray.h:175 [inline] xa_is_node include/linux/xarray.h:1270 [inline] max_index lib/xarray.c:435 [inline] xas_expand lib/xarray.c:586 [inline] xas_create+0x48c/0x1b90 lib/xarray.c:661 xas_store+0x95/0x1880 lib/xarray.c:795 __xa_store+0xe9/0x210 lib/xarray.c:1703 xa_store+0x33/0x50 lib/xarray.c:1734 list_netdevice+0x5ef/0x720 net/core/dev.c:423 register_netdevice+0x1773/0x1ec0 net/core/dev.c:11452 __ip_tunnel_create+0x3e8/0x560 net/ipv4/ip_tunnel.c:268 ip_tunnel_init_net+0x2e7/0x840 net/ipv4/ip_tunnel.c:1147 vti_init_net+0x2f/0x100 net/ipv4/ip_vti.c:517 ops_init+0x35c/0x5c0 net/core/net_namespace.c:137 setup_net+0x118/0x340 net/core/net_namespace.c:446 copy_net_ns+0x50e/0x730 net/core/net_namespace.c:579 create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:132 unshare_nsproxy_namespaces+0x149/0x190 kernel/nsproxy.c:234 ksys_unshare+0x57d/0x9f0 kernel/fork.c:3245 __do_sys_unshare kernel/fork.c:3319 [inline] __se_sys_unshare kernel/fork.c:3317 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3317 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0c5419cdd9 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:00007f0c550c0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f0c54415fa0 RCX: 00007f0c5419cdd9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007f0c54232d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0c54416038 R14: 00007f0c54415fa0 R15: 00007ffd565a6958 ---------------- Code disassembly (best guess): 0: 89 44 24 20 mov %eax,0x20(%rsp) 4: e8 f7 bf 74 fd call 0xfd74c000 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 a0 a5 28 8c mov $0xffffffff8c28a5a0,%rsi 1c: 48 c7 c2 20 ab 28 8c mov $0xffffffff8c28ab20,%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