audit: type=1400 audit(1586413385.512:15): avc: denied { create } for pid=8213 comm="syz-executor.1" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dccp_socket permissive=1 INFO: rcu_preempt self-detected stall on CPU 1-...: (10500 ticks this GP) idle=c36/140000000000002/0 softirq=12075/12075 fqs=0 (t=10500 jiffies g=2176 c=2175 q=741) rcu_preempt kthread starved for 10500 jiffies! g2176 c2175 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1 rcu_preempt R running task 29984 8 2 0x80000000 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x43c/0xe40 kernel/time/timer.c:1746 rcu_gp_kthread+0xb8e/0x1ce0 kernel/rcu/tree.c:2255 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 NMI backtrace for cpu 1 CPU: 1 PID: 8220 Comm: syz-executor.2 Not tainted 4.14.175-syzkaller #0 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+0x13e/0x194 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x139/0x17e lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:158 [inline] rcu_dump_cpu_stacks+0x16d/0x1b8 kernel/rcu/tree.c:1396 print_cpu_stall kernel/rcu/tree.c:1542 [inline] check_cpu_stall kernel/rcu/tree.c:1610 [inline] __rcu_pending kernel/rcu/tree.c:3390 [inline] rcu_pending kernel/rcu/tree.c:3452 [inline] rcu_check_callbacks.cold+0x490/0xdaa kernel/rcu/tree.c:2792 update_process_times+0x29/0x60 kernel/time/timer.c:1590 tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165 tick_sched_timer+0x3e/0x120 kernel/time/tick-sched.c:1223 __run_hrtimer kernel/time/hrtimer.c:1223 [inline] __hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287 hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline] smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:__read_once_size_nocheck.constprop.0+0x0/0x10 include/linux/compiler.h:201 RSP: 0018:ffff8880aeb07758 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff10 RAX: 0000000000000001 RBX: 1ffff11015d60eec RCX: 1ffff11015d60f11 RDX: ffff8880aeb07f00 RSI: ffff8880aeb07780 RDI: ffff8880aeb07ef8 RBP: ffff8880aeb07ef8 R08: 0000000000000000 R09: ffff8880aeb07e28 R10: ffff8880aeb078ad R11: 0000000000058071 R12: ffff8880aeb078b8 R13: dffffc0000000000 R14: ffff8880aeb07f28 R15: 0000000000000002 deref_stack_reg arch/x86/kernel/unwind_orc.c:292 [inline] deref_stack_reg+0x8a/0xc0 arch/x86/kernel/unwind_orc.c:286 unwind_next_frame+0xeff/0x17a0 arch/x86/kernel/unwind_orc.c:474 __save_stack_trace+0x6b/0xd0 arch/x86/kernel/stacktrace.c:44 save_stack+0x32/0xa0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:529 slab_post_alloc_hook mm/slab.h:442 [inline] slab_alloc_node mm/slab.c:3333 [inline] kmem_cache_alloc_node+0x135/0x7a0 mm/slab.c:3640 __alloc_skb+0x9a/0x4c0 net/core/skbuff.c:193 alloc_skb include/linux/skbuff.h:980 [inline] ndisc_alloc_skb+0x134/0x320 net/ipv6/ndisc.c:402 ndisc_send_rs+0x2ea/0x630 net/ipv6/ndisc.c:661 addrconf_rs_timer+0x289/0x5a0 net/ipv6/addrconf.c:3761 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279 expire_timers kernel/time/timer.c:1318 [inline] __run_timers kernel/time/timer.c:1636 [inline] __run_timers kernel/time/timer.c:1604 [inline] run_timer_softirq+0x52a/0x1390 kernel/time/timer.c:1649 __do_softirq+0x254/0x9bf kernel/softirq.c:288 invoke_softirq kernel/softirq.c:368 [inline] irq_exit+0x15b/0x1a0 kernel/softirq.c:409 exiting_irq arch/x86/include/asm/apic.h:648 [inline] smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:preempt_schedule_irq+0xa6/0x140 kernel/sched/core.c:3611 RSP: 0018:ffff8880868679e0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0fa2cd3 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8880503e4a3c RBP: ffffed100a07c838 R08: 000000330ce34564 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880503e41c0 R13: ffffffff87d16698 R14: 0000000000000000 R15: 0000000000000000 retint_kernel+0x1b/0x2d RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:60 RSP: 0018:ffff888086867ab8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 RAX: 0000000000040000 RBX: 000000000076bf0c RCX: ffffc9000a479000 RDX: 00000000000097bc RSI: ffffffff8150f0e4 RDI: ffff8880503e5618 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 1ffff11010d0cff9 R11: 0000000000000000 R12: ffff8880503e41c0 R13: dffffc0000000000 R14: 0000000000000000 R15: 000000000076b000 should_fail_futex kernel/futex.c:309 [inline] get_futex_key+0x7f8/0x1160 kernel/futex.c:573 futex_wake+0xc6/0x3d0 kernel/futex.c:1684 do_futex+0x264/0x1850 kernel/futex.c:3924 SYSC_futex kernel/futex.c:3980 [inline] SyS_futex+0x1e8/0x2c0 kernel/futex.c:3948 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c889 RSP: 002b:00007f5f8b529cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 000000000076bf08 RCX: 000000000045c889 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000076bf0c RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000076bf0c R13: 00007ffeed35650f R14: 00007f5f8b52a9c0 R15: 000000000076bf0c