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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 ffff888198d478e0 by task syz-executor.0/1726

CPU: 1 PID: 1726 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_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+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
 rcu_lock_acquire include/linux/rcupdate.h:242 [inline]
 rcu_read_lock include/linux/rcupdate.h:629 [inline]
 filemap_map_pages+0x122/0xc00 mm/filemap.c:2621
device nr0
 entered promiscuous mode
 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+0x3c3/0x6da mm/memory.c:4150
 faultin_page mm/gup.c:514 [inline]
 __get_user_pages+0x348/0xe80 mm/gup.c:716
 populate_vma_page_range+0x188/0x220 mm/gup.c:1235
 __mm_populate+0x1a5/0x2e0 mm/gup.c:1283
 mm_populate include/linux/mm.h:2224 [inline]
 vm_mmap_pgoff+0x1ab/0x1c0 mm/util.c:338
 SYSC_mmap_pgoff mm/mmap.c:1564 [inline]
 SyS_mmap_pgoff+0x146/0x1b0 mm/mmap.c:1520
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a679
RSP: 002b:00007f6f6384dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045a679
RDX: 0000000002000007 RSI: 0000000000600000 RDI: 00000000209fd000
RBP: 000000000075bf20 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000006031 R11: 0000000000000246 R12: 00007f6f6384e6d4
R13: 00000000004c70fe R14: 00000000004dd128 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea00066351c0 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:
 ffff888198d47780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888198d47800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888198d47880: 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 00 f3 f3 f3 00
                                                       ^
 ffff888198d47900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888198d47980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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