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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+0x368/0x3b0 arch/x86/kernel/unwind_frame.c:76
Read of size 8 at addr ffff8801ae727808 by task syz-executor0/12429

CPU: 0 PID: 12429 Comm: syz-executor0 Not tainted 4.9.129+ #49
 ffff8801cae6f690 ffffffff81b36939 ffffea0006b9c9c0 ffff8801ae727808
 0000000000000000 ffff8801ae727810 ffff8801affbdf00 ffff8801cae6f6c8
 ffffffff8150072d ffff8801ae727808 0000000000000008 0000000000000000
Call Trace:
 [<ffffffff81b36939>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b36939>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8150072d>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff81500b37>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff81500b37>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff814f2d44>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 [<ffffffff810acab8>] get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
 [<ffffffff810acab8>] __unwind_start+0x368/0x3b0 arch/x86/kernel/unwind_frame.c:76
 [<ffffffff81077939>] unwind_start arch/x86/include/asm/unwind.h:39 [inline]
 [<ffffffff81077939>] __save_stack_trace+0x59/0xf0 arch/x86/kernel/stacktrace.c:41
 [<ffffffff81077a38>] save_stack_trace_tsk+0x48/0x70 arch/x86/kernel/stacktrace.c:71
 [<ffffffff81665d98>] proc_pid_stack+0x148/0x220 fs/proc/base.c:469
 [<ffffffff8165e31d>] proc_single_show+0xfd/0x170 fs/proc/base.c:771
 [<ffffffff8157fac3>] traverse+0x363/0x920 fs/seq_file.c:124
 [<ffffffff8158115b>] seq_read+0xd1b/0x12d0 fs/seq_file.c:195
 [<ffffffff81509b65>] do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
 [<ffffffff8150c480>] do_loop_readv_writev fs/read_write.c:707 [inline]
 [<ffffffff8150c480>] compat_do_readv_writev+0x570/0x7b0 fs/read_write.c:1091
 [<ffffffff8150c7a2>] compat_readv+0xe2/0x150 fs/read_write.c:1120
 [<ffffffff8150cb32>] do_compat_preadv64+0x152/0x180 fs/read_write.c:1169
 [<ffffffff8150f0bb>] C_SYSC_preadv fs/read_write.c:1189 [inline]
 [<ffffffff8150f0bb>] compat_SyS_preadv+0x3b/0x50 fs/read_write.c:1183
 [<ffffffff81006311>] do_syscall_32_irqs_on arch/x86/entry/common.c:328 [inline]
 [<ffffffff81006311>] do_fast_syscall_32+0x2f1/0xa10 arch/x86/entry/common.c:390
 [<ffffffff82804260>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

The buggy address belongs to the page:
page:ffffea0006b9c9c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801ae727700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801ae727780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801ae727800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                         ^
 ffff8801ae727880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801ae727900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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