==================================================================
BUG: KASAN: stack-out-of-bounds in get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
BUG: KASAN: stack-out-of-bounds in __unwind_start+0x37c/0x3c0 arch/x86/kernel/unwind_frame.c:76
Read of size 8 at addr ffff8801bec5f768 by task syz-executor5/9443

CPU: 1 PID: 9443 Comm: syz-executor5 Not tainted 4.9.112-g9e79039 #59
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff88019ffbf770 ffffffff81eb3249 ffffea0006fb17c0 ffff8801bec5f768
 0000000000000000 ffff8801bec5f768 ffff88019ffbf8a8 ffff88019ffbf7a8
 ffffffff81567bd9 ffff8801bec5f768 0000000000000008 0000000000000000
Call Trace:
 [<ffffffff81eb3249>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb3249>] 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
 [<ffffffff810d324c>] get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
 [<ffffffff810d324c>] __unwind_start+0x37c/0x3c0 arch/x86/kernel/unwind_frame.c:76
 [<ffffffff8107b989>] unwind_start arch/x86/include/asm/unwind.h:39 [inline]
 [<ffffffff8107b989>] __save_stack_trace+0x59/0xf0 arch/x86/kernel/stacktrace.c:41
 [<ffffffff8107ba88>] save_stack_trace_tsk+0x48/0x70 arch/x86/kernel/stacktrace.c:71
 [<ffffffff816d7d08>] proc_pid_stack+0x148/0x220 fs/proc/base.c:469
 [<ffffffff816d93fd>] proc_single_show+0xfd/0x170 fs/proc/base.c:771
 [<ffffffff815ed406>] seq_read+0x4b6/0x12e0 fs/seq_file.c:240
 [<ffffffff8156f465>] do_loop_readv_writev.part.18+0xd5/0x280 fs/read_write.c:718
 [<ffffffff815733b5>] do_loop_readv_writev fs/read_write.c:707 [inline]
 [<ffffffff815733b5>] do_readv_writev+0x565/0x7a0 fs/read_write.c:873
 [<ffffffff81573674>] vfs_readv+0x84/0xc0 fs/read_write.c:897
 [<ffffffff81573796>] do_readv+0xe6/0x260 fs/read_write.c:923
 [<ffffffff81576ff7>] SYSC_readv fs/read_write.c:1010 [inline]
 [<ffffffff81576ff7>] SyS_readv+0x27/0x30 fs/read_write.c:1007
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9f53>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

The buggy address belongs to the page:
page:ffffea0006fb17c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801bec5f600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801bec5f680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801bec5f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                          ^
 ffff8801bec5f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801bec5f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================