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BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x169f/0x1810 arch/x86/kernel/unwind_orc.c:470
Read of size 8 at addr ffff88819283f860 by task syz-executor.0/16336

CPU: 1 PID: 16336 Comm: syz-executor.0 Not tainted 4.14.156-syzkaller #0
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xe5/0x154 lib/dump_stack.c:58
 print_address_description+0x60/0x226 mm/kasan/report.c:187
 __kasan_report.cold+0x1a/0x41 mm/kasan/report.c:316
 unwind_next_frame+0x169f/0x1810 arch/x86/kernel/unwind_orc.c:470
 perf_callchain_kernel+0x3a0/0x540 arch/x86/events/core.c:2338
 get_perf_callchain+0x2f5/0x770 kernel/events/callchain.c:217
 perf_callchain+0x147/0x190 kernel/events/callchain.c:190
 perf_prepare_sample+0x6a8/0x1360 kernel/events/core.c:6149
 __perf_event_output kernel/events/core.c:6265 [inline]
 perf_event_output_backward+0xdc/0x220 kernel/events/core.c:6291
 __perf_event_overflow+0x12d/0x340 kernel/events/core.c:7541
 perf_swevent_overflow+0x7a/0xf0 kernel/events/core.c:7617
 perf_swevent_event+0x112/0x270 kernel/events/core.c:7655
 perf_tp_event+0x633/0x7f0 kernel/events/core.c:8079
 perf_trace_run_bpf_submit kernel/events/core.c:8049 [inline]
 perf_trace_run_bpf_submit+0x113/0x170 kernel/events/core.c:8035
 perf_trace_lock_acquire+0x341/0x4e0 include/trace/events/lock.h:13
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0x279/0x360 kernel/locking/lockdep.c:3993
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
 spin_lock include/linux/spinlock.h:317 [inline]
 queue_lock kernel/futex.c:2238 [inline]
 futex_wait_setup+0x132/0x330 kernel/futex.c:2677
 futex_wait+0x1ad/0x570 kernel/futex.c:2735
 do_futex+0x13f/0x1980 kernel/futex.c:3663
 SYSC_futex kernel/futex.c:3723 [inline]
 SyS_futex+0x1c5/0x2c3 kernel/futex.c:3691
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a649
RSP: 002b:00007f295ebdccf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000075bf28 RCX: 000000000045a649
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075bf28
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075bf2c
R13: 00007ffec164569f R14: 00007f295ebdd9c0 R15: 000000000075bf2c

The buggy address belongs to the page:
page:ffffea00064a0fc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 dead000000000200 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88819283f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88819283f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88819283f800: 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 00 f3 f3 f3 00
                                                       ^
 ffff88819283f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88819283f900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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