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BUG: KASAN: out-of-bounds in unwind_next_frame+0xd7/0xe0 arch/x86/kernel/unwind_frame.c:51
Read of size 8 at addr ffff8801acdbf900 by task syz-executor1/5417

CPU: 0 PID: 5417 Comm: syz-executor1 Not tainted 4.9.83-ga92bb8d #43
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801acc377c8 ffffffff81d95149 ffffea0006b36fc0 ffff8801acdbf900
 0000000000000000 ffff8801acdbf908 0000000000000000 ffff8801acc37800
 ffffffff8153e213 ffff8801acdbf900 0000000000000008 0000000000000000
Call Trace:
 [<ffffffff81d95149>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d95149>] 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
 [<ffffffff810d4fe7>] unwind_next_frame+0xd7/0xe0 arch/x86/kernel/unwind_frame.c:51
 [<ffffffff8107c65d>] __save_stack_trace+0x7d/0xf0 arch/x86/kernel/stacktrace.c:42
 [<ffffffff8107c738>] save_stack_trace_tsk+0x48/0x70 arch/x86/kernel/stacktrace.c:71
 [<ffffffff816c5a96>] proc_pid_stack+0x146/0x230 fs/proc/base.c:466
 [<ffffffff816c7268>] proc_single_show+0xf8/0x170 fs/proc/base.c:768
 [<ffffffff815e92ef>] 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
 [<ffffffff81006504>] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282
 [<ffffffff838b4e7d>] entry_SYSCALL_64_after_swapgs+0x47/0xc5

The buggy address belongs to the page:
page:ffffea0006b36fc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801acdbf800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801acdbf880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801acdbf900: 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2 f3 f3 f3 f3
                      ^
 ffff8801acdbf980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
 ffff8801acdbfa00: f1 f1 f1 00 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00
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