ODEBUG: free active (active state 0) object type: timer_list hint: led_timeout_callback+0x0/0x20 include/linux/compiler.h:210 WARNING: CPU: 1 PID: 4151 at lib/debugobjects.c:291 debug_print_object+0x166/0x220 lib/debugobjects.c:288 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 4151 Comm: syzkaller931127 Not tainted 4.16.0-rc1+ #223 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 panic+0x1e4/0x41c kernel/panic.c:183 __warn+0x1dc/0x200 kernel/panic.c:547 report_bug+0x211/0x2d0 lib/bug.c:184 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/kernel/traps.c:247 [inline] do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:988 RIP: 0010:debug_print_object+0x166/0x220 lib/debugobjects.c:288 RSP: 0018:ffff8801b942f630 EFLAGS: 00010082 RAX: dffffc0000000008 RBX: 0000000000000003 RCX: ffffffff815aaf3e RDX: 0000000000000000 RSI: 1ffff10037285e76 RDI: 1ffff10037285e4b RBP: ffff8801b942f670 R08: 0000000000000000 R09: 1ffff10037285e1d R10: ffffed0037285ef5 R11: ffffffff86b39478 R12: 0000000000000001 R13: ffffffff86b4ace0 R14: ffffffff86007c60 R15: ffffffff815fd9a0 __debug_check_no_obj_freed lib/debugobjects.c:745 [inline] debug_check_no_obj_freed+0x662/0xf1f lib/debugobjects.c:774 kfree+0xc7/0x260 mm/slab.c:3799 led_tg_destroy+0x28a/0x3f0 net/netfilter/xt_LED.c:192 cleanup_entry+0x218/0x350 net/ipv4/netfilter/ip_tables.c:654 __do_replace+0x79d/0xa50 net/ipv4/netfilter/ip_tables.c:1089 do_replace net/ipv4/netfilter/ip_tables.c:1145 [inline] do_ipt_set_ctl+0x40f/0x5f0 net/ipv4/netfilter/ip_tables.c:1675 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1259 tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2905 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x444aca RSP: 002b:00007ffeeaa90e18 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00000000006cf9c0 RCX: 0000000000444aca RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000006cf9c0 R08: 00000000000002d8 R09: 0000000000004000 R10: 00000000006cf960 R11: 0000000000000206 R12: 00007ffeeaa90e40 R13: 00000000006d1b80 R14: 0000000000000003 R15: 0000000000000000 ====================================================== WARNING: possible circular locking dependency detected 4.16.0-rc1+ #223 Not tainted ------------------------------------------------------ syzkaller931127/4151 is trying to acquire lock: ((console_sem).lock){..-.}, at: [<000000002058f59f>] down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 but task is already holding lock: (&obj_hash[i].lock){-.-.}, at: [<000000001414457a>] __debug_check_no_obj_freed lib/debugobjects.c:736 [inline] (&obj_hash[i].lock){-.-.}, at: [<000000001414457a>] debug_check_no_obj_freed+0x1e9/0xf1f lib/debugobjects.c:774 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&obj_hash[i].lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 __debug_object_init+0x109/0x1040 lib/debugobjects.c:343 debug_object_init+0x17/0x20 lib/debugobjects.c:391 debug_hrtimer_init kernel/time/hrtimer.c:410 [inline] debug_init kernel/time/hrtimer.c:458 [inline] hrtimer_init+0x8c/0x410 kernel/time/hrtimer.c:1259 init_dl_task_timer+0x1b/0x50 kernel/sched/deadline.c:1060 __sched_fork+0x2bb/0xb60 kernel/sched/core.c:2189 init_idle+0x75/0x820 kernel/sched/core.c:5347 sched_init+0xb19/0xc43 kernel/sched/core.c:6044 start_kernel+0x452/0x819 init/main.c:585 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378 x86_64_start_kernel+0x77/0x7a arch/x86/kernel/head64.c:359 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:237 -> #2 (&rq->lock){-.-.}: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144 rq_lock kernel/sched/sched.h:1760 [inline] task_fork_fair+0x7a/0x690 kernel/sched/fair.c:9471 sched_fork+0x450/0xc10 kernel/sched/core.c:2405 copy_process.part.37+0x1758/0x4b60 kernel/fork.c:1774 copy_process kernel/fork.c:1617 [inline] _do_fork+0x1f7/0xf70 kernel/fork.c:2098 kernel_thread+0x34/0x40 kernel/fork.c:2157 rest_init+0x22/0xf0 init/main.c:402 start_kernel+0x7f1/0x819 init/main.c:716 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378 x86_64_start_kernel+0x77/0x7a arch/x86/kernel/head64.c:359 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:237 -> #1 (&p->pi_lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 try_to_wake_up+0xbc/0x15f0 kernel/sched/core.c:1989 wake_up_process+0x10/0x20 kernel/sched/core.c:2152 __up.isra.0+0x1cc/0x2c0 kernel/locking/semaphore.c:262 up+0x13b/0x1d0 kernel/locking/semaphore.c:187 __up_console_sem+0xb2/0x1a0 kernel/printk/printk.c:242 console_unlock+0x5af/0xfb0 kernel/printk/printk.c:2417 vprintk_emit+0x5c3/0xb90 kernel/printk/printk.c:1907 vprintk_default+0x28/0x30 kernel/printk/printk.c:1947 vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 printk+0xaa/0xca kernel/printk/printk.c:1980 kauditd_printk_skb kernel/audit.c:506 [inline] kauditd_hold_skb+0x163/0x180 kernel/audit.c:539 kauditd_send_queue+0xfa/0x140 kernel/audit.c:702 kauditd_thread+0x660/0x940 kernel/audit.c:828 kthread+0x33c/0x400 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:429 -> #0 ((console_sem).lock){..-.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xa2/0x1e0 kernel/printk/printk.c:225 console_trylock+0x15/0x70 kernel/printk/printk.c:2229 console_trylock_spinning kernel/printk/printk.c:1643 [inline] vprintk_emit+0x5b5/0xb90 kernel/printk/printk.c:1906 vprintk_default+0x28/0x30 kernel/printk/printk.c:1947 vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 printk+0xaa/0xca kernel/printk/printk.c:1980 __warn_printk+0x90/0xf0 kernel/panic.c:599 debug_print_object+0x166/0x220 lib/debugobjects.c:288 __debug_check_no_obj_freed lib/debugobjects.c:745 [inline] debug_check_no_obj_freed+0x662/0xf1f lib/debugobjects.c:774 kfree+0xc7/0x260 mm/slab.c:3799 led_tg_destroy+0x28a/0x3f0 net/netfilter/xt_LED.c:192 cleanup_entry+0x218/0x350 net/ipv4/netfilter/ip_tables.c:654 __do_replace+0x79d/0xa50 net/ipv4/netfilter/ip_tables.c:1089 do_replace net/ipv4/netfilter/ip_tables.c:1145 [inline] do_ipt_set_ctl+0x40f/0x5f0 net/ipv4/netfilter/ip_tables.c:1675 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1259 tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2905 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b other info that might help us debug this: Chain exists of: (console_sem).lock --> &rq->lock --> &obj_hash[i].lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&obj_hash[i].lock); lock(&rq->lock); lock(&obj_hash[i].lock); lock((console_sem).lock); *** DEADLOCK *** 2 locks held by syzkaller931127/4151: #0: (&xt[i].mutex){+.+.}, at: [<00000000e2834500>] xt_find_table_lock+0x3e/0x3e0 net/netfilter/x_tables.c:1046 #1: (&obj_hash[i].lock){-.-.}, at: [<000000001414457a>] __debug_check_no_obj_freed lib/debugobjects.c:736 [inline] #1: (&obj_hash[i].lock){-.-.}, at: [<000000001414457a>] debug_check_no_obj_freed+0x1e9/0xf1f lib/debugobjects.c:774 stack backtrace: CPU: 1 PID: 4151 Comm: syzkaller931127 Not tainted 4.16.0-rc1+ #223 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_circular_bug.isra.38+0x2cd/0x2dc kernel/locking/lockdep.c:1223 check_prev_add kernel/locking/lockdep.c:1863 [inline] check_prevs_add kernel/locking/lockdep.c:1976 [inline] validate_chain kernel/locking/lockdep.c:2417 [inline] __lock_acquire+0x30a8/0x3e00 kernel/locking/lockdep.c:3431 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xa2/0x1e0 kernel/printk/printk.c:225 console_trylock+0x15/0x70 kernel/printk/printk.c:2229 console_trylock_spinning kernel/printk/printk.c:1643 [inline] vprintk_emit+0x5b5/0xb90 kernel/printk/printk.c:1906 vprintk_default+0x28/0x30 kernel/printk/printk.c:1947 vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 printk+0xaa/0xca kernel/printk/printk.c:1980 __warn_printk+0x90/0xf0 kernel/panic.c:599 debug_print_object+0x166/0x220 lib/debugobjects.c:288 __debug_check_no_obj_freed lib/debugobjects.c:745 [inline] debug_check_no_obj_freed+0x662/0xf1f lib/debugobjects.c:774 kfree+0xc7/0x260 mm/slab.c:3799 led_tg_destroy+0x28a/0x3f0 net/netfilter/xt_LED.c:192 cleanup_entry+0x218/0x350 net/ipv4/netfilter/ip_tables.c:654 __do_replace+0x79d/0xa50 net/ipv4/netfilter/ip_tables.c:1089 do_replace net/ipv4/netfilter/ip_tables.c:1145 [inline] do_ipt_set_ctl+0x40f/0x5f0 net/ipv4/netfilter/ip_tables.c:1675 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1259 tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2905 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x444aca RSP: 002b:00007ffeeaa90e18 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00000000006cf9c0 RCX: 0000000000444aca RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000006cf9c0 R08: 00000000000002d8 R09: 0000000000004000 R10: 00000000006cf960 R11: 0000000000000206 R12: 00007ffeeaa90e40 R13: 00000000006d1b80 R14: 0000000000000003 R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..