executing program syzkaller login: [ 13.122260] BUG: unable to handle kernel NULL pointer dereference at 0000000000000055 [ 13.122888] IP: 0x55 [ 13.123060] PGD 3b1ca067 [ 13.123062] P4D 3b1ca067 [ 13.123243] PUD 3b12f067 [ 13.123424] PMD 0 [ 13.123769] [ 13.124064] Oops: 0010 [#1] SMP KASAN [ 13.124377] Dumping ftrace buffer: [ 13.124658] (ftrace buffer empty) [ 13.124912] Modules linked in: [ 13.125111] CPU: 2 PID: 1194 Comm: kworker/u8:1 Not tainted 4.13.0-rc4-next-20170811 #2 [ 13.125645] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 13.126207] Workqueue: kstrp strp_work [ 13.126472] task: ffff88006bb0e480 task.stack: ffff88006bb10000 [ 13.126897] RIP: 0010:0x55 [ 13.127120] RSP: 0018:ffff88006bb17540 EFLAGS: 00010246 [ 13.127946] RAX: dffffc0000000000 RBX: ffff88006ce4bd60 RCX: 0000000000000000 [ 13.128460] RDX: 1ffff1000d9c97bd RSI: 0000000000000000 RDI: ffff88006ce4bc48 [ 13.128936] RBP: ffff88006bb17558 R08: ffffffff81467ab2 R09: 0000000000000000 [ 13.129407] R10: ffff88006bb17438 R11: ffff88006bb17940 R12: ffff88006ce4bc48 [ 13.129880] R13: ffff88003c683018 R14: ffff88006bb17980 R15: ffff88003c683000 [ 13.130394] FS: 0000000000000000(0000) GS:ffff88006de00000(0000) knlGS:0000000000000000 [ 13.130969] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 13.131343] CR2: 0000000000000055 CR3: 000000003c145000 CR4: 00000000000006e0 [ 13.131806] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 13.132275] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 13.132894] Call Trace: [ 13.133095] ? strp_work+0x41/0xf0 [ 13.133354] process_one_work+0xbf3/0x1bc0 [ 13.133638] ? pwq_dec_nr_in_flight+0x450/0x450 [ 13.133942] ? preempt_notifier_dec+0x20/0x20 [ 13.134227] ? sched_clock_cpu+0x1b/0x170 [ 13.134492] ? __schedule+0x8f0/0x2070 [ 13.134745] ? lock_acquire+0x1d5/0x580 [ 13.134993] ? lock_acquire+0x1d5/0x580 [ 13.135248] ? select_task_rq_fair+0xec9/0x3380 [ 13.135542] ? lock_downgrade+0x990/0x990 [ 13.135812] ? lock_release+0xa40/0xa40 [ 13.136073] ? lock_acquire+0x1d5/0x580 [ 13.136374] ? lock_acquire+0x1d5/0x580 [ 13.136626] ? worker_thread+0x4a3/0x1860 [ 13.136902] ? lock_downgrade+0x990/0x990 [ 13.137177] ? lock_release+0xa40/0xa40 [ 13.137433] ? do_raw_spin_trylock+0x190/0x190 [ 13.137724] ? retint_kernel+0x10/0x10 [ 13.137977] worker_thread+0x223/0x1860 [ 13.138236] ? process_one_work+0x1bc0/0x1bc0 [ 13.138525] ? pvclock_read_flags+0x160/0x160 [ 13.138819] ? __schedule+0x8b7/0x2070 [ 13.139072] ? trace_hardirqs_on+0xd/0x10 [ 13.139336] ? _raw_spin_unlock_irq+0x27/0x70 [ 13.139624] ? finish_task_switch+0x1d3/0x740 [ 13.139913] ? finish_task_switch+0x1aa/0x740 [ 13.140204] ? preempt_notifier_dec+0x20/0x20 [ 13.140493] ? sched_clock_cpu+0x104/0x170 [ 13.140768] ? __schedule+0x8f0/0x2070 [ 13.141015] ? __x2apic_send_IPI_dest.constprop.7+0x5b/0x80 [ 13.141382] ? try_to_wake_up+0xf9/0x1600 [ 13.141654] ? migrate_swap_stop+0x970/0x970 [ 13.141938] ? lock_acquire+0x1d5/0x580 [ 13.142197] ? fs_reclaim_acquire+0x20/0x20 [ 13.142480] ? lock_acquire+0x1d5/0x580 [ 13.142732] ? lock_acquire+0x1d5/0x580 [ 13.142988] ? complete+0x62/0x80 [ 13.143215] ? __schedule+0x2070/0x2070 [ 13.143472] ? __lockdep_init_map+0xe4/0x650 [ 13.143818] ? default_wake_function+0x30/0x50 [ 13.144117] ? __init_waitqueue_head+0x97/0x140 [ 13.144428] ? __wake_up_common+0xb4/0x150 [ 13.144699] ? trace_hardirqs_on+0xd/0x10 [ 13.144968] ? __kthread_parkme+0x173/0x240 [ 13.145263] kthread+0x35e/0x430 [ 13.145481] ? process_one_work+0x1bc0/0x1bc0 [ 13.145767] ? kthread_create_on_node+0x100/0x100 [ 13.146082] ret_from_fork+0x2a/0x40 [ 13.146321] Code: Bad RIP value. [ 13.146548] RIP: 0x55 RSP: ffff88006bb17540 [ 13.146823] CR2: 0000000000000055 [ 13.147049] ---[ end trace f0e4920047069cee ]--- [ 13.147351] Kernel panic - not syncing: Fatal exception [ 13.147740] Dumping ftrace buffer: [ 13.147962] (ftrace buffer empty) [ 13.148197] Kernel Offset: disabled [ 13.149021] Rebooting in 86400 seconds..