crash: segfault in ubuntu20.04

[Jeff0083]

environment

• ubuntu version

jeff-kvm@ubuntu:/var/crash$ uname -r
5.13.0-17-generic

• crash version

jeff-kvm@ubuntu:/var/crash$ crash -v

crash 7.2.8
...
GNU gdb (GDB) 7.6
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-unknown-linux-gnu".

Description of problem:

root@ubuntu:/var/crash/202110312024# crash dump.202110312024 /home/jeff-kvm/Downloads/jeff/usr/lib/debug/boot/vmlinux-5.13.0-17-generic

crash 7.2.8
Copyright (C) 2002-2020  Red Hat, Inc.
Copyright (C) 2004, 2005, 2006, 2010  IBM Corporation
Copyright (C) 1999-2006  Hewlett-Packard Co
Copyright (C) 2005, 2006, 2011, 2012  Fujitsu Limited
Copyright (C) 2006, 2007  VA Linux Systems Japan K.K.
Copyright (C) 2005, 2011  NEC Corporation
Copyright (C) 1999, 2002, 2007  Silicon Graphics, Inc.
Copyright (C) 1999, 2000, 2001, 2002  Mission Critical Linux, Inc.
This program is free software, covered by the GNU General Public License,
and you are welcome to change it and/or distribute copies of it under
certain conditions.  Enter "help copying" to see the conditions.
This program has absolutely no warranty.  Enter "help warranty" for details.
 
GNU gdb (GDB) 7.6
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-unknown-linux-gnu"...

WARNING: kernel relocated [362MB]: patching 139284 gdb minimal_symbol values

please wait... (patching 139284 gdb minimal_symbol values) Segmentation fault (core dumped)

And we can see the following error report(see dmesg):

[ 1198.548759] crash[3580]: segfault at 7ffffc57dff8 ip 0000560ea1af5ec0 sp 00007ffffc57e000 error 6 in crash[560ea1ad9000+43f000]
[ 1198.548768] Code: 05 a5 3d 6c 00 48 39 78 08 0f 97 c0 0f b6 c0 c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 41 57 41 89 f7 41 56 41 55 49 89 cd <41> 54 49 89 fc 55 48 89 d5 53 4c 89 cb 48 83 ec 48 4c 89 04 24 64

And we can see the crash-utility proc mem map(_usr_bin_crash.0.crash):

....

 7fb97b7d4000-7fb97b7d5000 rw-p 0002d000 08:05 2234671                    /usr/lib/x86_64-linux-gnu/ld-2.31.so
 7fb97b7d5000-7fb97b7d6000 rw-p 00000000 00:00 0
 7ffffc57e000-7ffffcd7e000 rw-p 00000000 00:00 0                          [stack]
 7ffffcdb1000-7ffffcdb5000 r--p 00000000 00:00 0                          [vvar]
 7ffffcdb5000-7ffffcdb7000 r-xp 00000000 00:00 0                          [vdso]
 ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]
...
ProcStatus:

it seems that it's stack overflow,because segfault at 7ffffc57dff8,but the [stack]: 7ffffc57e000-7ffffcd7e000

How to reproducible

always Steps to Reproduce:

1. Generate a vmcore with the sysrq
2. crash vmlinux vmcore

Actual results:

Segmentation fault (core dumped)

Expected results:

crash can work as expected.

[k-hagio]

If you are using an Ubuntu's crash, please consult Ubuntu support about it first. If you are using an upstream crash, please try the latest crash, crash-7.2.8 is too old to be used for kernel 5.13.