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BUG: KASAN: out-of-bounds in unwind_get_return_address+0x98/0xb0 arch/x86/kernel/unwind_frame.c:17
Read of size 8 at addr ffff8801a04278e8 by task syz-executor5/12829

CPU: 1 PID: 12829 Comm: syz-executor5 Not tainted 4.9.113-g9905591 #66
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801a07bf8e0 ffffffff81eb32a9 ffffea00068109c0 ffff8801a04278e8
 0000000000000000 ffff8801a04278f0 ffff8801ba068a00 ffff8801a07bf918
 ffffffff81567bd9 ffff8801a04278e8 0000000000000008 0000000000000000
Call Trace:
 [<ffffffff81eb32a9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb32a9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81567bd9>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff81567fe3>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff81567fe3>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff8153bc34>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 [<ffffffff810d2c68>] unwind_get_return_address+0x98/0xb0 arch/x86/kernel/unwind_frame.c:17
 [<ffffffff8107b9bd>] __save_stack_trace+0x8d/0xf0 arch/x86/kernel/stacktrace.c:43
 [<ffffffff8107ba88>] save_stack_trace_tsk+0x48/0x70 arch/x86/kernel/stacktrace.c:71
 [<ffffffff816d7d68>] proc_pid_stack+0x148/0x220 fs/proc/base.c:469
 [<ffffffff816d945d>] proc_single_show+0xfd/0x170 fs/proc/base.c:771
 [<ffffffff815ed466>] seq_read+0x4b6/0x12e0 fs/seq_file.c:240
 [<ffffffff81570ef5>] __vfs_read+0x115/0x570 fs/read_write.c:449
 [<ffffffff815726c0>] vfs_read+0x120/0x380 fs/read_write.c:472
 [<ffffffff81576719>] SYSC_read fs/read_write.c:588 [inline]
 [<ffffffff81576719>] SyS_read+0xd9/0x1c0 fs/read_write.c:581
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fa193>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

The buggy address belongs to the page:
page:ffffea00068109c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801a0427780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801a0427800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801a0427880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                             ^
 ffff8801a0427900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801a0427980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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