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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 ffff8881cd127a00 by task syz-executor152/2035

CPU: 0 PID: 2035 Comm: syz-executor152 Not tainted 4.14.154+ #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_forward+0xdc/0x220 kernel/events/core.c:6283
 __perf_event_overflow+0x12d/0x340 kernel/events/core.c:7541
 perf_swevent_overflow+0x7a/0xf0 kernel/events/core.c:7617
 perf_swevent_event+0x19c/0x270 kernel/events/core.c:7650
 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
 rcu_lock_acquire include/linux/rcupdate.h:242 [inline]
 rcu_read_lock include/linux/rcupdate.h:629 [inline]
 lock_page_memcg+0x36/0x290 mm/memcontrol.c:1669
 page_add_file_rmap+0x25/0x260 mm/rmap.c:1180
 alloc_set_pte+0x42d/0xec0 mm/memory.c:3448
 filemap_map_pages+0x8e4/0xc00 mm/filemap.c:2675
 do_fault_around mm/memory.c:3594 [inline]
 do_read_fault mm/memory.c:3628 [inline]
 do_fault mm/memory.c:3759 [inline]
 handle_pte_fault mm/memory.c:3989 [inline]
 __handle_mm_fault+0x17fc/0x2700 mm/memory.c:4113
 handle_mm_fault+0x2f1/0x6da mm/memory.c:4150
 __do_page_fault+0x477/0xbb0 arch/x86/mm/fault.c:1420
 page_fault+0x42/0x50 arch/x86/entry/entry_64.S:1122
RIP: 6d2180:          (null)
RSP: 0001:00007ffcc52e2850 EFLAGS: 00000001

The buggy address belongs to the page:
page:ffffea00073449c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea00073449e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881cd127900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881cd127980: 00 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 00
>ffff8881cd127a00: f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff8881cd127a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881cd127b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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