Free memory is 63244kB above reserved
lowmemorykiller: Killing 'syz-executor.3' (16593) (tgid 16593), adj 1000,
   to free 8340kB on behalf of 'syz-executor.4' (17803) because
   cache 8776kB is below limit 65536kB for oom_score_adj 12
   Free memory is 62624kB above reserved
INFO: rcu_preempt detected stalls on CPUs/tasks:
	Tasks blocked on level-0 rcu_node (CPUs 0-1): P33
	(detected by 1, t=10502 jiffies, g=3771, c=3770, q=176348)
kswapd0         R  running task    27968    33      2 0x80000008
 0000012d82a59e80 ffffffff841ca2c0 1ffff1003b083ead 0000000100000005
 0000000041b58ab3 ffffffff82e60a80 ffffffff81d6f5c0 ffffffff81b6e700
 0000000000000020 ffff880100000020 ffff8801d841f628 ffff8801d841f5d0
Call Trace:
==================================================================
BUG: KASAN: stack-out-of-bounds in get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
BUG: KASAN: stack-out-of-bounds in __unwind_start+0x368/0x3b0 arch/x86/kernel/unwind_frame.c:76
Read of size 8 at addr ffff8801d841f570 by task syz-executor.0/2204

CPU: 1 PID: 2204 Comm: syz-executor.0 Not tainted 4.9.141+ #23
 ffff8801db707a00 ffffffff81b42e79 ffffea00076107c0 ffff8801d841f570
 0000000000000000 ffff8801d841f570 ffff8801d99217c0 ffff8801db707a38
 ffffffff815009b8 ffff8801d841f570 0000000000000008 0000000000000000
Call Trace:
 <IRQ> 
 [<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff815009b8>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff81500dc2>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff81500dc2>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff814f3074>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 [<ffffffff810acd08>] get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
 [<ffffffff810acd08>] __unwind_start+0x368/0x3b0 arch/x86/kernel/unwind_frame.c:76
 [<ffffffff810cab91>] unwind_start arch/x86/include/asm/unwind.h:39 [inline]
 [<ffffffff810cab91>] show_trace_log_lvl+0x92/0x1c8 arch/x86/kernel/dumpstack.c:70
 [<ffffffff810ca923>] show_stack_log_lvl.cold.1+0x22/0xbe arch/x86/kernel/dumpstack_64.c:188
 [<ffffffff8105a72d>] show_stack+0x4d/0x50 arch/x86/kernel/dumpstack.c:168
 [<ffffffff813fa6fd>] sched_show_task.cold.35+0x279/0x31f kernel/sched/core.c:5317
 [<ffffffff81404e39>] rcu_print_detail_task_stall_rnp+0xc2/0xfe kernel/rcu/tree_plugin.h:530
 [<ffffffff81405f5f>] rcu_print_detail_task_stall kernel/rcu/tree_plugin.h:543 [inline]
 [<ffffffff81405f5f>] print_other_cpu_stall kernel/rcu/tree.c:1408 [inline]
 [<ffffffff81405f5f>] check_cpu_stall kernel/rcu/tree.c:1520 [inline]
 [<ffffffff81405f5f>] __rcu_pending kernel/rcu/tree.c:3487 [inline]
 [<ffffffff81405f5f>] rcu_pending kernel/rcu/tree.c:3551 [inline]
 [<ffffffff81405f5f>] rcu_check_callbacks.cold.69+0x757/0xd27 kernel/rcu/tree.c:2880
 [<ffffffff81267470>] update_process_times+0x30/0x70 kernel/time/timer.c:1629
 [<ffffffff8129641a>] tick_sched_handle.isra.5+0x4a/0xf0 kernel/time/tick-sched.c:151
 [<ffffffff81296536>] tick_sched_timer+0x76/0x130 kernel/time/tick-sched.c:1190
 [<ffffffff8126a197>] __run_hrtimer kernel/time/hrtimer.c:1255 [inline]
 [<ffffffff8126a197>] __hrtimer_run_queues+0x357/0xe30 kernel/time/hrtimer.c:1319
 [<ffffffff8126c681>] hrtimer_interrupt+0x1b1/0x430 kernel/time/hrtimer.c:1353
 [<ffffffff810912d4>] local_apic_timer_interrupt+0x74/0xa0 arch/x86/kernel/apic/apic.c:937
 [<ffffffff8281b76c>] smp_apic_timer_interrupt+0x7c/0xb0 arch/x86/kernel/apic/apic.c:961
 [<ffffffff8281902d>] apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:648
 <EOI> 
 [<ffffffff819f7f75>] rcu_read_lock include/linux/rcupdate.h:876 [inline]
 [<ffffffff819f7f75>] task_has_perm+0x245/0x330 security/selinux/hooks.c:1611
 [<ffffffff819f8083>] selinux_task_wait+0x23/0x30 security/selinux/hooks.c:3954
 [<ffffffff819e6e73>] security_task_wait+0x73/0xb0 security/security.c:1032
 [<ffffffff810e91f1>] wait_consider_task+0x2a1/0x3620 kernel/exit.c:1377
 [<ffffffff810ec993>] do_wait_thread kernel/exit.c:1490 [inline]
 [<ffffffff810ec993>] do_wait+0x423/0x950 kernel/exit.c:1561
 [<ffffffff810eda0b>] SYSC_wait4 kernel/exit.c:1693 [inline]
 [<ffffffff810eda0b>] SyS_wait4+0x12b/0x1f0 kernel/exit.c:1658
 [<ffffffff812bf054>] C_SYSC_wait4 kernel/compat.c:543 [inline]
 [<ffffffff812bf054>] compat_SyS_wait4+0x254/0x290 kernel/compat.c:536
 [<ffffffff810c6305>] sys32_waitpid+0x25/0x30 arch/x86/ia32/sys_ia32.c:172
 [<ffffffff81006311>] do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
 [<ffffffff81006311>] do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
 [<ffffffff82818de0>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

The buggy address belongs to the page:
page:ffffea00076107c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d841f400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801d841f480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801d841f500: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1
                                                             ^
 ffff8801d841f580: f1 04 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 04 f2
 ffff8801d841f600: f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================