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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 ffff8801735a77c8 by task syz-executor1/18489

CPU: 0 PID: 18489 Comm: syz-executor1 Not tainted 4.9.147+ #86
 ffff8801a57af158 ffffffff81b43be9 ffffea0005cd69c0 ffff8801735a77c8
 0000000000000000 ffff8801735a77d0 ffff8801aacd17c0 ffff8801a57af190
 ffffffff81500cd8 ffff8801735a77c8 0000000000000008 0000000000000000
Call Trace:
 [<ffffffff81b43be9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b43be9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81500cd8>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff815010e2>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff815010e2>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff814f3394>] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 [<ffffffff810acd98>] get_frame_pointer arch/x86/include/asm/stacktrace.h:64 [inline]
 [<ffffffff810acd98>] __unwind_start+0x368/0x3b0 arch/x86/kernel/unwind_frame.c:76
 [<ffffffff81077bf9>] unwind_start arch/x86/include/asm/unwind.h:39 [inline]
 [<ffffffff81077bf9>] __save_stack_trace+0x59/0xf0 arch/x86/kernel/stacktrace.c:41
 [<ffffffff81077cf8>] save_stack_trace_tsk+0x48/0x70 arch/x86/kernel/stacktrace.c:71
 [<ffffffff81666c3f>] proc_pid_stack+0x18f/0x290 fs/proc/base.c:483
 [<ffffffff8165f17d>] proc_single_show+0xfd/0x170 fs/proc/base.c:785
 [<ffffffff81581506>] seq_read+0x4b6/0x12d0 fs/seq_file.c:240
 [<ffffffff8150a115>] do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
 [<ffffffff8150b7be>] do_loop_readv_writev fs/read_write.c:707 [inline]
 [<ffffffff8150b7be>] do_readv_writev+0x56e/0x7b0 fs/read_write.c:873
 [<ffffffff8150ba84>] vfs_readv+0x84/0xc0 fs/read_write.c:897
 [<ffffffff815acbc1>] kernel_readv fs/splice.c:363 [inline]
 [<ffffffff815acbc1>] default_file_splice_read+0x451/0x7f0 fs/splice.c:435
 [<ffffffff815abcbc>] do_splice_to+0x10c/0x170 fs/splice.c:899
 [<ffffffff815abf5f>] splice_direct_to_actor+0x23f/0x7e0 fs/splice.c:971
 [<ffffffff815ac6a3>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff8150daa0>] do_sendfile+0x4f0/0xc30 fs/read_write.c:1393
 [<ffffffff8150fb84>] SYSC_sendfile64 fs/read_write.c:1454 [inline]
 [<ffffffff8150fb84>] SyS_sendfile64+0x144/0x160 fs/read_write.c:1440
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff8281a4d3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

The buggy address belongs to the page:
page:ffffea0005cd69c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801735a7680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801735a7700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801735a7780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                 ^
 ffff8801735a7800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801735a7880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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