syzbot

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=53a/1/0x4000000000000004 softirq=292911/292913 fqs=7 
rcu: 	 (t=10500 jiffies g=451753 q=112)
rcu: rcu_preempt kthread starved for 10484 jiffies! g451753 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29136    10      2 0x80000000
Call Trace:
 schedule+0x8d/0x1b0 kernel/sched/core.c:3559
 schedule_timeout+0x4d1/0xf20 kernel/time/timer.c:1806
 rcu_gp_kthread+0xcee/0x2060 kernel/rcu/tree.c:2202
 kthread+0x34a/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
NMI backtrace for cpu 1
CPU: 1 PID: 3958 Comm: syz-executor.0 Not tainted 4.19.119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x170/0x1bb kernel/rcu/tree.c:1340
 print_cpu_stall kernel/rcu/tree.c:1478 [inline]
 check_cpu_stall kernel/rcu/tree.c:1550 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0x634/0xddc kernel/rcu/tree.c:2682
 update_process_times+0x2a/0x70 kernel/time/timer.c:1638
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168
 tick_sched_timer+0x42/0x130 kernel/time/tick-sched.c:1278
 __run_hrtimer kernel/time/hrtimer.c:1401 [inline]
 __hrtimer_run_queues+0x2fc/0xd50 kernel/time/hrtimer.c:1463
 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1521
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x50/0x80 kernel/locking/spinlock.c:192
Code: c0 d8 56 d2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d 51 db b0 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 76 3f 25 fa 65 8b 05 2f 72 e0 78 85 c0 74 02 5d
RSP: 0018:ffff8880ae707df8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a4adb RBX: ffff8880ae707e70 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88801be68e44
RBP: ffff8880ae723a00 R08: ffff88801be685c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffffffff85b1f0d0 R14: ffff8880ae723a00 R15: ffff88808d44b590
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1684 [inline]
 __run_timers kernel/time/timer.c:1652 [inline]
 run_timer_softirq+0x5c5/0x1540 kernel/time/timer.c:1697
 __do_softirq+0x26c/0x93c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x17b/0x1c0 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:544 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
 </IRQ>
RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:67
Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01
RSP: 0018:ffff88821677fbe0 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 1ffff11011d33800 RBX: ffffed1011d338d8 RCX: 0000000000000000
RDX: 0000000000000008 RSI: 0000000000000000 RDI: ffffed1011d338d8
RBP: 0000000000000040 R08: ffff88801be685c0 R09: ffffed1011d338d0
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000488020
R13: ffff88808e99c6bf R14: ffff88812c39c340 R15: ffff88808e99c6bf
 kasan_poison_shadow mm/kasan/kasan.c:64 [inline]
 kasan_unpoison_shadow+0x30/0x40 mm/kasan/kasan.c:69
 kasan_kmalloc+0x45/0xe0 mm/kasan/kasan.c:548
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc mm/slab.c:3397 [inline]
 kmem_cache_alloc_trace+0x137/0x7a0 mm/slab.c:3623
 kmalloc include/linux/slab.h:515 [inline]
 kzalloc include/linux/slab.h:709 [inline]
 netlbl_secattr_alloc include/net/netlabel.h:396 [inline]
 selinux_netlbl_sock_genattr+0xac/0x420 security/selinux/netlabel.c:90
 selinux_netlbl_socket_post_create+0x73/0x160 security/selinux/netlabel.c:412
 selinux_socket_post_create+0x4c7/0x7a0 security/selinux/hooks.c:4631
 security_socket_post_create+0x80/0xc0 security/security.c:1381
 __sock_create+0x5b2/0x740 net/socket.c:1292
 sock_create net/socket.c:1316 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1346
 __do_sys_socket net/socket.c:1355 [inline]
 __se_sys_socket net/socket.c:1353 [inline]
 __x64_sys_socket+0x6f/0xb0 net/socket.c:1353
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c829
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f4e6c29cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 0000000000506880 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0800000000000002 RDI: 000000000000000a
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000b75 R14: 00000000004cda79 R15: 00007f4e6c29d6d4