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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 ffff8881d1a0fcd8 by task syz-executor.5/26190

CPU: 1 PID: 26190 Comm: syz-executor.5 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
 __might_fault mm/memory.c:4584 [inline]
 __might_fault+0x137/0x1b0 mm/memory.c:4569
 _copy_to_user+0x27/0xd0 lib/usercopy.c:25
 copy_to_user include/linux/uaccess.h:155 [inline]
 put_timespec64+0xb2/0x110 kernel/time/time.c:920
 SYSC_clock_gettime kernel/time/posix-stubs.c:92 [inline]
 SyS_clock_gettime+0xbd/0xe0 kernel/time/posix-stubs.c:82
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45d4ba
RSP: 002b:00007f4ffef53c58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e4
RAX: ffffffffffffffda RBX: 000000000075c078 RCX: 000000000045d4ba
RDX: 0000000000000000 RSI: 00007f4ffef53c60 RDI: 0000000000000001
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075c07c
R13: 00000000004c14a3 R14: 00000000004d4ad0 R15: 000000000075c07c

The buggy address belongs to the page:
page:ffffea00074683c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 dead000000000200 ffff8881d2e8a4d0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881d1a0fb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881d1a0fc00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881d1a0fc80: 00 00 f1 f1 f1 f1 f1 f1 04 f2 00 f3 f3 f3 00 00
                                                    ^
 ffff8881d1a0fd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881d1a0fd80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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