==================================================================
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x1360/0x17d0 arch/x86/kernel/unwind_orc.c:477
Read of size 8 at addr ffff88809304f8e8 by task syz-executor287/20217

CPU: 1 PID: 20217 Comm: syz-executor287 Not tainted 4.14.196-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:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430
 unwind_next_frame+0x1360/0x17d0 arch/x86/kernel/unwind_orc.c:477
 perf_callchain_kernel+0x38c/0x520 arch/x86/events/core.c:2343
 get_perf_callchain+0x2df/0x740 kernel/events/callchain.c:217
 perf_callchain+0x147/0x190 kernel/events/callchain.c:190
 perf_prepare_sample+0xd77/0x1380 kernel/events/core.c:6162
 __perf_event_output kernel/events/core.c:6278 [inline]
 perf_event_output_forward+0xc9/0x1f0 kernel/events/core.c:6296
 __perf_event_overflow+0x113/0x310 kernel/events/core.c:7541
 perf_swevent_hrtimer+0x220/0x350 kernel/events/core.c:8751
 __run_hrtimer kernel/time/hrtimer.c:1223 [inline]
 __hrtimer_run_queues+0x30b/0xc80 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+0x93/0xa0 arch/x86/entry/entry_64.S:793
 </IRQ>
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:774 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:796 [inline]
RIP: 0010:lock_acquire+0x97/0x3f0 kernel/locking/lockdep.c:3993
RSP: 0018:ffff88809304f810 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0fa2d20 RBX: ffff88808325e3c0 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88808325ec44
RBP: ffff88808325f5c8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88808325e3c0 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
 perf_remove_from_owner kernel/events/core.c:4307 [inline]
 perf_event_release_kernel+0x4b4/0x8a0 kernel/events/core.c:4353
 retint_kernel+0x2d/0x2d
RIP: 41b58ab3:lock_acquire+0x170/0x3f0
RSP: 0286:ffffffff81474ae0 EFLAGS: ffffffff8789374c ORIG_RAX: ffff88808325ec40
RAX: ffffffff8a5a5c00 RBX: ffffffff9660dc60 RCX: ffff88808325e3c0
RDX: 0000000000000001 RSI: 0000000000000286 RDI: 0000000000000286
RBP: ffff88821f8b9680 R08: ffffffff816c063a R09: ffffffff87d84e60
R10: 1ffff11012609f2a R11: 0000000000000286 R12: ffffffff8653c1f0
R13: ffffffff87893410 R14: 0000000041b58ab3 R15: ffff88807f98d5b0

The buggy address belongs to the page:
page:ffffea00024c13c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0xfffe0000000000()
raw: 00fffe0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809304f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88809304f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88809304f880: 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00
                                                          ^
 ffff88809304f900: 00 f2 00 00 00 f2 f2 f2 00 00 00 00 00 f3 f3 f3
 ffff88809304f980: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================