netlink: 16 bytes leftover after parsing attributes in process `syz-executor4'.
netlink: 16 bytes leftover after parsing attributes in process `syz-executor4'.
INFO: rcu_sched self-detected stall on CPU
	1-...!: (1 GPs behind) idle=b1e/1/4611686018427387906 softirq=48198/48200 fqs=850 
	 (t=120000 jiffies g=28526 c=28525 q=56)
rcu_sched kthread starved for 116595 jiffies! g28526 c28525 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
RCU grace-period kthread stack dump:
rcu_sched       R  running task    61960     9      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2880 [inline]
 __schedule+0x651/0x770 kernel/sched/core.c:3524
 schedule+0x1cc/0x2f0 kernel/sched/core.c:3568
 schedule_timeout+0x3ef/0x580 kernel/time/timer.c:1801
 rcu_gp_kthread+0x21e1/0x38d0 kernel/rcu/tree.c:2231
 kthread+0x4db/0x6c0 kernel/kthread.c:241
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:413
NMI backtrace for cpu 1
CPU: 1 PID: 10323 Comm: syz-executor7 Not tainted 4.17.0+ #9
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+0x185/0x1d0 lib/dump_stack.c:113
 nmi_cpu_backtrace lib/nmi_backtrace.c:103 [inline]
 nmi_trigger_cpumask_backtrace+0x262/0x4c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x2c/0x40 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline]
 rcu_dump_cpu_stacks+0x307/0x4b0 kernel/rcu/tree.c:1376
 print_cpu_stall kernel/rcu/tree.c:1525 [inline]
 check_cpu_stall kernel/rcu/tree.c:1593 [inline]
 __rcu_pending kernel/rcu/tree.c:3356 [inline]
 rcu_pending kernel/rcu/tree.c:3401 [inline]
 rcu_check_callbacks+0x11c5/0x2ae0 kernel/rcu/tree.c:2763
 update_process_times+0x132/0x1a0 kernel/time/timer.c:1636
 tick_sched_handle kernel/time/tick-sched.c:164 [inline]
 tick_sched_timer+0x3ba/0x520 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0xc54/0x1630 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x451/0x13c0 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt+0x6b/0x250 arch/x86/kernel/apic/apic.c:1025
 smp_apic_timer_interrupt+0x5a/0x90 arch/x86/kernel/apic/apic.c:1053
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:866
 </IRQ>
RIP: 0010:do_make_slave fs/pnode.c:101 [inline]
RIP: 0010:change_mnt_propagation+0x1f2/0x1850 fs/pnode.c:128
RSP: 0018:ffff8800b716fa00 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff8800ba801b20 RCX: ffff8800ba801b00
RDX: ffffc9000a7e0000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffff8800b716fac0 R08: 0000000001080000 R09: ffff8800b39169f0
R10: 0000000000000000 R11: 000000000000017c R12: ffffffffffffff58
R13: ffff8801d6306000 R14: ffff8801d630b480 R15: 0000000000000000
 umount_tree+0x2400/0x2500 fs/namespace.c:1524
 attach_recursive_mnt+0x378c/0x3c70 fs/namespace.c:2069
 graft_tree fs/namespace.c:2133 [inline]
 do_loopback fs/namespace.c:2254 [inline]
 do_mount+0x3e4a/0x4ed0 fs/namespace.c:2842
 ksys_mount+0x32e/0x3d0 fs/namespace.c:3064
 __do_sys_mount fs/namespace.c:3078 [inline]
 __se_sys_mount fs/namespace.c:3075 [inline]
 __x64_sys_mount+0x157/0x1c0 fs/namespace.c:3075
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455b29
RSP: 002b:00007f41a24fcc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f41a24fd6d4 RCX: 0000000000455b29
RDX: 0000000020753000 RSI: 0000000020187ff8 RDI: 0000000020000480
RBP: 000000000072c370 R08: 0000000020000100 R09: 0000000000000000
R10: 000000000000500c R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c1f17 R14: 00000000004cf5b0 R15: 0000000000000007