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BUG: KASAN: out-of-bounds in get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
BUG: KASAN: out-of-bounds in __unwind_start+0x3a7/0x3c0 arch/x86/kernel/unwind_frame.c:76
Read of size 8 at addr ffff8801c5107ab8 by task syz-executor2/16743

CPU: 1 PID: 16743 Comm: syz-executor2 Not tainted 4.9.82-gcdfc8df #37
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801c3e6f788 ffffffff81d94fc9 ffffea00071441c0 ffff8801c5107ab8
 0000000000000000 ffff8801c5107ac0 ffff8801c3e6f8b8 ffff8801c3e6f7c0
 ffffffff8153e213 ffff8801c5107ab8 0000000000000008 0000000000000000
Call Trace:
 [<ffffffff81d94fc9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d94fc9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8153e213>] print_address_description+0x73/0x280 mm/kasan/report.c:252
 [<ffffffff8153e735>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8153e735>] kasan_report+0x275/0x360 mm/kasan/report.c:408
 [<ffffffff8153e894>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:429
 [<ffffffff810d5397>] get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
 [<ffffffff810d5397>] __unwind_start+0x3a7/0x3c0 arch/x86/kernel/unwind_frame.c:76
 [<ffffffff8107c639>] unwind_start arch/x86/include/asm/unwind.h:39 [inline]
 [<ffffffff8107c639>] __save_stack_trace+0x59/0xf0 arch/x86/kernel/stacktrace.c:41
 [<ffffffff8107c738>] save_stack_trace_tsk+0x48/0x70 arch/x86/kernel/stacktrace.c:71
 [<ffffffff816c5a76>] proc_pid_stack+0x146/0x230 fs/proc/base.c:466
 [<ffffffff816c7248>] proc_single_show+0xf8/0x170 fs/proc/base.c:768
 [<ffffffff815e92cf>] seq_read+0x32f/0x1290 fs/seq_file.c:240
 [<ffffffff8156cda1>] do_loop_readv_writev.part.17+0x141/0x1e0 fs/read_write.c:714
 [<ffffffff81570c10>] do_loop_readv_writev fs/read_write.c:880 [inline]
 [<ffffffff81570c10>] do_readv_writev+0x520/0x750 fs/read_write.c:874
 [<ffffffff81570ec4>] vfs_readv+0x84/0xc0 fs/read_write.c:898
 [<ffffffff81570fe6>] do_readv+0xe6/0x250 fs/read_write.c:924
 [<ffffffff815744d7>] SYSC_readv fs/read_write.c:1011 [inline]
 [<ffffffff815744d7>] SyS_readv+0x27/0x30 fs/read_write.c:1008
 [<ffffffff81006505>] do_syscall_64+0x1a5/0x490 arch/x86/entry/common.c:282
 [<ffffffff838b4e7d>] entry_SYSCALL_64_after_swapgs+0x47/0xc5

The buggy address belongs to the page:
page:ffffea00071441c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c5107980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801c5107a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801c5107a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                           ^
 ffff8801c5107b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801c5107b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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