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BUG: KASAN: out-of-bounds in deref_stack_regs arch/x86/kernel/unwind_orc.c:290 [inline]
BUG: KASAN: out-of-bounds in unwind_next_frame+0x1595/0x1930 arch/x86/kernel/unwind_orc.c:420
Read of size 8 at addr ffff88019df4f818 by task syz-executor1/25085

CPU: 1 PID: 25085 Comm: syz-executor1 Not tainted 4.14.76+ #20
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 print_address_description+0x60/0x22b mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409
 deref_stack_regs arch/x86/kernel/unwind_orc.c:290 [inline]
 unwind_next_frame+0x1595/0x1930 arch/x86/kernel/unwind_orc.c:420
 __save_stack_trace+0x7d/0xf0 arch/x86/kernel/stacktrace.c:44
 save_stack_trace_tsk+0x3e/0x60 arch/x86/kernel/stacktrace.c:73
 proc_pid_stack+0x17c/0x260 fs/proc/base.c:460
 proc_single_show+0xf1/0x160 fs/proc/base.c:762
 seq_read+0x4e0/0x11d0 fs/seq_file.c:237
 do_loop_readv_writev fs/read_write.c:698 [inline]
 do_iter_read+0x3cc/0x580 fs/read_write.c:922
 vfs_readv+0xe6/0x150 fs/read_write.c:984
 do_preadv+0x187/0x230 fs/read_write.c:1068
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x457569
RSP: 002b:00007fae9f29dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569
RDX: 1000000000000156 RSI: 0000000020000480 RDI: 0000000000000006
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fae9f29e6d4
R13: 00000000004c3088 R14: 00000000004d4a40 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea000677d3c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea000677d3e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88019df4f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88019df4f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88019df4f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                               ^
 ffff88019df4f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88019df4f900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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