netlink: 3 bytes leftover after parsing attributes in process `syz-executor4'. INFO: rcu_sched self-detected stall on CPU 0-....: (120158 ticks this GP) idle=8b2/1/4611686018427387906 softirq=28144/28144 fqs=28502 (t=125000 jiffies g=12309 c=12308 q=989) NMI backtrace for cpu 0 CPU: 0 PID: 18072 Comm: syz-executor2 Not tainted 4.14.0-rc5-next-20171018+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 nmi_cpu_backtrace+0x20e/0x240 lib/nmi_backtrace.c:102 nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:61 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 trigger_single_cpu_backtrace include/linux/nmi.h:155 [inline] rcu_dump_cpu_stacks+0x186/0x1da kernel/rcu/tree.c:1377 print_cpu_stall kernel/rcu/tree.c:1526 [inline] check_cpu_stall.isra.65+0xbb8/0x15b0 kernel/rcu/tree.c:1594 __rcu_pending kernel/rcu/tree.c:3358 [inline] rcu_pending kernel/rcu/tree.c:3420 [inline] rcu_check_callbacks+0x238/0xd20 kernel/rcu/tree.c:2760 update_process_times+0x30/0x60 kernel/time/timer.c:1590 tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:162 tick_sched_timer+0x42/0x120 kernel/time/tick-sched.c:1192 __run_hrtimer kernel/time/hrtimer.c:1213 [inline] __hrtimer_run_queues+0x349/0xe10 kernel/time/hrtimer.c:1277 hrtimer_interrupt+0x1c2/0x5e0 kernel/time/hrtimer.c:1311 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline] smp_apic_timer_interrupt+0x14a/0x700 arch/x86/kernel/apic/apic.c:1050 apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:577 RIP: 0010:_raw_spin_lock_irqsave+0x0/0xc0 RSP: 0018:ffff88002d7c75a8 EFLAGS: 00000283 ORIG_RAX: ffffffffffffff11 RAX: dffffc0000000000 RBX: ffff88002d7c7868 RCX: ffffffff83eda262 RDX: ffff88002d7c7678 RSI: ffff88002d7c7870 RDI: ffff880038c706c0 RBP: ffff88002d7c76a0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88002d7c7850 R13: 1ffff10005af8ebb R14: ffff880038c70240 R15: ffff880038c706c0 sock_wait_for_wmem net/core/sock.c:2039 [inline] sock_alloc_send_pskb+0x64f/0x9b0 net/core/sock.c:2076 tun_alloc_skb drivers/net/tun.c:1349 [inline] tun_get_user+0x91a/0x36d0 drivers/net/tun.c:1636 tun_chr_write_iter+0xb9/0x160 drivers/net/tun.c:1792 call_write_iter include/linux/fs.h:1770 [inline] new_sync_write fs/read_write.c:468 [inline] __vfs_write+0x684/0x970 fs/read_write.c:481 vfs_write+0x189/0x510 fs/read_write.c:543 SYSC_write fs/read_write.c:588 [inline] SyS_write+0xef/0x220 fs/read_write.c:580 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x447c89 RSP: 002b:00007f8959b7ebd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8959b7f6cc RCX: 0000000000447c89 RDX: 000000000000276b RSI: 0000000020de9895 RDI: 0000000000000014 RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000004d10 R14: 00000000006e8db0 R15: 00007f8959b7f700 INFO: task kworker/u8:1:1211 blocked for more than 120 seconds. Not tainted 4.14.0-rc5-next-20171018+ #8 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u8:1 D20256 1211 2 0x80000000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:2798 [inline] __schedule+0x8eb/0x2060 kernel/sched/core.c:3374 schedule+0xf5/0x430 kernel/sched/core.c:3433 schedule_timeout+0x1d7/0x270 kernel/time/timer.c:1731 do_wait_for_common kernel/sched/completion.c:90 [inline] __wait_for_common kernel/sched/completion.c:111 [inline] wait_for_common kernel/sched/completion.c:122 [inline] wait_for_completion+0x415/0x770 kernel/sched/completion.c:143 __wait_rcu_gp+0x23f/0x3e0 kernel/rcu/update.c:413 synchronize_sched.part.68+0xac/0x100 kernel/rcu/tree.c:3209 synchronize_sched+0x76/0xf0 kernel/rcu/tree.c:3210 synchronize_rcu include/linux/rcupdate.h:94 [inline] synchronize_net+0x34/0x50 net/core/dev.c:8230 xfrm_user_net_exit+0x106/0x1f0 net/xfrm/xfrm_user.c:3211 ops_exit_list.isra.6+0x100/0x150 net/core/net_namespace.c:145 cleanup_net+0x5c7/0xb50 net/core/net_namespace.c:483 process_one_work+0xbf0/0x1bc0 kernel/workqueue.c:2112 worker_thread+0x223/0x1990 kernel/workqueue.c:2246 kthread+0x38b/0x470 kernel/kthread.c:242 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 Showing all locks held in the system: 2 locks held by khungtaskd/672: #0: (rcu_read_lock){....}, at: [] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.?}, at: [] debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4541 3 locks held by kworker/u8:1/1211: #0: ("%s""netns"){+.+.}, at: [] __write_once_size include/linux/compiler.h:305 [inline] #0: ("%s""netns"){+.+.}, at: [] atomic64_set arch/x86/include/asm/atomic64_64.h:33 [inline] #0: ("%s""netns"){+.+.}, at: [] atomic_long_set include/asm-generic/atomic-long.h:56 [inline] #0: ("%s""netns"){+.+.}, at: [] set_work_data kernel/workqueue.c:618 [inline] #0: ("%s""netns"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:645 [inline] #0: ("%s""netns"){+.+.}, at: [] process_one_work+0xadf/0x1bc0 kernel/workqueue.c:2083 #1: (net_cleanup_work){+.+.}, at: [] process_one_work+0xb32/0x1bc0 kernel/workqueue.c:2087 #2: (net_mutex){+.+.}, at: [] cleanup_net+0x247/0xb50 net/core/net_namespace.c:449 2 locks held by getty/2952: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2133 2 locks held by getty/2953: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2133 2 locks held by getty/2954: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2133 2 locks held by getty/2955: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2133 2 locks held by getty/2956: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2133 2 locks held by getty/2957: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2133 2 locks held by getty/2958: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2133 2 locks held by zwlan1%/18035: #0: (cpu_hotplug_lock.rw_sem){++++}, at: [] get_online_cpus include/linux/cpu.h:126 [inline] #0: (cpu_hotplug_lock.rw_sem){++++}, at: [] lru_add_drain_all+0xe/0x20 mm/swap.c:729 #1: (lock#5){+.+.}, at: [] lru_add_drain_all_cpuslocked+0xb2/0x4f0 mm/swap.c:704 1 lock held by syz-executor5/18091: #0: (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 kernel/trace/trace_event_perf.c:234 3 locks held by syz-executor4/18100: #0: (&sig->cred_guard_mutex){+.+.}, at: [] SYSC_perf_event_open+0x12ca/0x2e00 kernel/events/core.c:10018 #1: (&pmus_srcu){....}, at: [] perf_event_alloc+0x1036/0x2990 kernel/events/core.c:9579 #2: (event_mutex){+.+.}, at: [] perf_trace_init+0x58/0xab0 kernel/trace/trace_event_perf.c:216 ============================================= NMI backtrace for cpu 3 CPU: 3 PID: 672 Comm: khungtaskd Not tainted 4.14.0-rc5-next-20171018+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 nmi_cpu_backtrace+0x20e/0x240 lib/nmi_backtrace.c:102 nmi_trigger_cpumask_backtrace+0x122/0x180 lib/nmi_backtrace.c:61 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 trigger_all_cpu_backtrace include/linux/nmi.h:137 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0x90c/0xd60 kernel/hung_task.c:249 kthread+0x38b/0x470 kernel/kthread.c:242 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 Sending NMI from CPU 3 to CPUs 0-2: NMI backtrace for cpu 1 CPU: 1 PID: 2867 Comm: rs:main Q:Reg Not tainted 4.14.0-rc5-next-20171018+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88006b7e63c0 task.stack: ffff880068e08000 RIP: 0010:check_kcov_mode kernel/kcov.c:66 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x1a/0x50 kernel/kcov.c:100 RSP: 0018:ffff880068e0f158 EFLAGS: 00000246 RAX: ffff88006b7e63c0 RBX: ffffffff87035900 RCX: ffffffff81a16f41 RDX: 0000000000000000 RSI: ffffffff87035900 RDI: ffffffff87035908 RBP: ffff880068e0f158 R08: 0000000000000001 R09: 1ffff1000d1c1dd7 R10: ffff880068e0ee80 R11: 0000000000000003 R12: 0000000000000000 R13: 0000000001c200ca R14: 0000000000000001 R15: ffff88006c773870 FS: 00007f401ad54700(0000) GS:ffff88003ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb4b289d000 CR3: 000000006aab6000 CR4: 00000000000006e0 DR0: 0000000020000000 DR1: 0000000020000008 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: policy_node+0x64/0x110 mm/mempolicy.c:1677 alloc_pages_current+0xa6/0x1e0 mm/mempolicy.c:2033 alloc_pages include/linux/gfp.h:496 [inline] __page_cache_alloc+0x334/0x500 mm/filemap.c:946 pagecache_get_page+0x287/0xba0 mm/filemap.c:1576 grab_cache_page_write_begin+0x6c/0xa0 mm/filemap.c:3088 ext4_da_write_begin+0x335/0x1020 fs/ext4/inode.c:3036 generic_perform_write+0x28f/0x600 mm/filemap.c:3138 __generic_file_write_iter+0x366/0x5b0 mm/filemap.c:3263 ext4_file_write_iter+0x5c2/0x10c0 fs/ext4/file.c:264 call_write_iter include/linux/fs.h:1770 [inline] new_sync_write fs/read_write.c:468 [inline] __vfs_write+0x684/0x970 fs/read_write.c:481 vfs_write+0x189/0x510 fs/read_write.c:543 SYSC_write fs/read_write.c:588 [inline] SyS_write+0xef/0x220 fs/read_write.c:580 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x7f401c7b219d RSP: 002b:00007f401ad53000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000169 RCX: 00007f401c7b219d RDX: 0000000000000169 RSI: 0000000001ff7340 RDI: 0000000000000001 RBP: 0000000000000082 R08: 0a306178302f3061 R09: 65736572203f2020 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000002000c40 R13: 0000000000000000 R14: 0000000000000003 R15: 00000000000000c0 Code: e9 c3 fc ff ff 90 90 90 90 90 90 90 90 90 90 90 90 55 65 48 8b 04 25 c0 64 01 00 48 89 e5 65 8b 15 9c a5 92 7e 81 e2 00 01 1f 00 <48> 8b 4d 08 75 2b 8b 90 28 12 00 00 83 fa 02 75 20 48 8b b0 30 NMI backtrace for cpu 0 CPU: 0 PID: 18072 Comm: syz-executor2 Not tainted 4.14.0-rc5-next-20171018+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88003d0721c0 task.stack: ffff88002d7c0000 RIP: 0010:mark_lock+0x220/0x13d0 kernel/locking/lockdep.c:3157 RSP: 0018:ffff88002d7c6d38 EFLAGS: 00000082 RAX: 0000000000000000 RBX: 0000000000000008 RCX: ffffed0005af8dab RDX: ffff88003d072a50 RSI: 1ffff10007a0e54a RDI: ffffed0005af8db3 RBP: ffff88002d7c6f60 R08: ffffffff81529e4d R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000006 R12: ffff88003d072a30 R13: 0000000000000100 R14: 0000000000000001 R15: 1ffff10005af8dab FS: 00007f8959b7f700(0000) GS:ffff88003ec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020f2d000 CR3: 0000000038a30000 CR4: 00000000000006f0 DR0: 0000000020001008 DR1: 0000000020001000 DR2: 0000000020001000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __lock_acquire+0x6aa/0x3d50 kernel/locking/lockdep.c:3448 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3991 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:157 finish_wait+0x11d/0x490 kernel/sched/wait.c:368 sock_wait_for_wmem net/core/sock.c:2039 [inline] sock_alloc_send_pskb+0x64f/0x9b0 net/core/sock.c:2076 tun_alloc_skb drivers/net/tun.c:1349 [inline] tun_get_user+0x91a/0x36d0 drivers/net/tun.c:1636 tun_chr_write_iter+0xb9/0x160 drivers/net/tun.c:1792 call_write_iter include/linux/fs.h:1770 [inline] new_sync_write fs/read_write.c:468 [inline] __vfs_write+0x684/0x970 fs/read_write.c:481 vfs_write+0x189/0x510 fs/read_write.c:543 SYSC_write fs/read_write.c:588 [inline] SyS_write+0xef/0x220 fs/read_write.c:580 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x447c89 RSP: 002b:00007f8959b7ebd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8959b7f6cc RCX: 0000000000447c89 RDX: 000000000000276b RSI: 0000000020de9895 RDI: 0000000000000014 RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000004d10 R14: 00000000006e8db0 R15: 00007f8959b7f700 Code: 30 74 4d 41 be 01 00 00 00 48 b9 00 00 00 00 00 fc ff df 31 c0 4c 01 f9 48 8d 79 08 48 c7 01 00 00 00 00 48 c7 41 34 00 00 00 00 <48> 83 e7 f8 48 29 f9 83 c1 3c c1 e9 03 f3 48 ab 48 81 c4 00 02 NMI backtrace for cpu 2 skipped: idling at pc 0xffffffff84e54ea6 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.055 msecs