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BUG: KASAN: stack-out-of-bounds in get_reg arch/x86/kernel/unwind_orc.c:384 [inline]
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x161c/0x1c60 arch/x86/kernel/unwind_orc.c:550
Read of size 8 at addr ffff888095fef800 by task syz-executor737/8099

CPU: 0 PID: 8099 Comm: syz-executor737 Not tainted 4.19.179-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 get_reg arch/x86/kernel/unwind_orc.c:384 [inline]
 unwind_next_frame+0x161c/0x1c60 arch/x86/kernel/unwind_orc.c:550
 perf_callchain_kernel+0x3fa/0x5c0 arch/x86/events/core.c:2346
 get_perf_callchain+0x392/0x860 kernel/events/callchain.c:202
 perf_callchain+0x165/0x1c0 kernel/events/core.c:6450
 perf_prepare_sample+0x81e/0x1620 kernel/events/core.c:6477
 __perf_event_output kernel/events/core.c:6592 [inline]
 perf_event_output_forward+0xf3/0x270 kernel/events/core.c:6610
 __perf_event_overflow+0x13c/0x370 kernel/events/core.c:7883
 perf_swevent_overflow kernel/events/core.c:7959 [inline]
 perf_swevent_event+0x347/0x550 kernel/events/core.c:7987
 perf_tp_event+0x29f/0xaa0 kernel/events/core.c:8415
 perf_trace_run_bpf_submit+0x144/0x220 kernel/events/core.c:8389
 perf_trace_lock_acquire+0x36b/0x530 include/trace/events/lock.h:13
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0x298/0x3c0 kernel/locking/lockdep.c:3906
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:152
 __debug_check_no_obj_freed lib/debugobjects.c:776 [inline]
 debug_check_no_obj_freed+0xb5/0x490 lib/debugobjects.c:817
 free_pages_prepare mm/page_alloc.c:1056 [inline]
 free_pcp_prepare mm/page_alloc.c:1070 [inline]
 free_unref_page_prepare+0x1ea/0x5d0 mm/page_alloc.c:2763
 free_unref_page+0x20/0x170 mm/page_alloc.c:2812
 pte_free arch/x86/include/asm/pgalloc.h:65 [inline]
 zap_deposited_table mm/huge_memory.c:1738 [inline]
 zap_huge_pmd+0xa00/0xe90 mm/huge_memory.c:1792
 zap_pmd_range mm/memory.c:1439 [inline]
 zap_pud_range mm/memory.c:1481 [inline]
 zap_p4d_range mm/memory.c:1502 [inline]
 unmap_page_range+0xe4d/0x2a70 mm/memory.c:1523
 unmap_single_vma+0x198/0x300 mm/memory.c:1568
 unmap_vmas+0xa9/0x180 mm/memory.c:1598
 exit_mmap+0x2b9/0x530 mm/mmap.c:3093
 __mmput kernel/fork.c:1015 [inline]
 mmput+0x14e/0x4a0 kernel/fork.c:1036
 exit_mm kernel/exit.c:549 [inline]
 do_exit+0xaec/0x2be0 kernel/exit.c:857
 do_group_exit+0x125/0x310 kernel/exit.c:967
 __do_sys_exit_group kernel/exit.c:978 [inline]
 __se_sys_exit_group kernel/exit.c:976 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:976
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43e9c9
Code: 00 49 c7 c0 c0 ff ff ff be e7 00 00 00 ba 3c 00 00 00 eb 12 0f 1f 44 00 00 89 d0 0f 05 48 3d 00 f0 ff ff 77 1c f4 89 f0 0f 05 <48> 3d 00 f0 ff ff 76 e7 f7 d8 64 41 89 00 eb df 0f 1f 80 00 00 00
RSP: 002b:00007ffedfbbccc8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00000000004b02f0 RCX: 000000000043e9c9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000000000001
R10: 00000000ffffffff R11: 0000000000000246 R12: 00000000004b02f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001

The buggy address belongs to the page:
page:ffffea000257fbc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0xfff00000000000()
raw: 00fff00000000000 0000000000000000 ffffffff02570101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888095fef700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888095fef780: 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 00 f3
>ffff888095fef800: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff888095fef880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888095fef900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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