Hi,
Suddenly 'mc 4.8.19' starts throwing segfaults each time I search for contents in multiple files, e.g. in a directory structure like '/usr/local/bin'. Searching in SINGLE files or in a directory which contains only *.sh-files is ok):
... 07:42:32 kernel: mc[17515]: segfault at a39349a0 ip a2fbdf81 sp b0f41af4 error 4 in libpcre.so.1.2.9[a2f94000+44000] 07:42:32 kernel: grsec: From 192.168.100.1: Segmentation fault occurred at a39349a0 in /usr/bin/m c[mc:17515] uid/euid:0/0 gid/egid:0/0, parent /bin/bash[bash:16795] uid/euid:0/0 gid/egid:0/0 07:42:32 kernel: grsec: From 192.168.100.1: denied resource overstep by requesting 4096 for RLIMIT_CORE against limit 0 for /usr/bin/mc[mc:17515] uid/euid:0/0 gid/egid:0/0, parent /bin/bash[bash:16795] uid/euid:0/0 gid/egid:0/0 ...
The same happens on a fresh test installation.
Right now I'm thinking about using 'paxctl' on '/usr/bin/mc', but I'm not really sure...:
1. If this would be a solution 2. Which options to use - and 3. On which parts ('/usr/bin/mc'?) exactly.
I'm testing with:
... paxctl -cm /usr/bin/mc ...
But had no luck until now.
Anybody got a hint or experiencing the same?
Best, Matthias
Hi,
On 03.10.2017 08:50, Matthias Fischer wrote:
...
Suddenly 'mc 4.8.19' starts throwing segfaults...
...
This is weird.
As soon as directory (e.g. '/usr/local/bin') contains the file 'ipfirereboot', 'mc' crashes while searching for content 'flush' (e.g.).
Thus, I would say, 'mc' has problems searching in (specific) binaries - searching in '/usr/bin' has the same effect.
And:
The following 'paxctl'-options had NO effect:
... root@ipfire: /usr/bin # paxctl -v /usr/bin/mc PaX control v0.9 Copyright 2004,2005,2006,2007,2009,2010,2011,2012,2014 PaX Team pageexec@freemail.hu
- PaX flags: -p-s-m-x-e-- [/usr/bin/mc] PAGEEXEC is disabled SEGMEXEC is disabled MPROTECT is disabled RANDEXEC is disabled EMUTRAMP is disabled ...
Searching in text-only files is ok, but as soon as directory contains the above file (or something similar), 'mc' crashes.
This does NOT happen on my devel with 'mc 4.8.15'... ;-)
Best, Matthias
Hi,
this doesn't have anything to do with PaX. It's just a bug in mc.
Probably has this problem with files that have the SUID bit set?!
Did you try to update mc?
-Michael
On Tue, 2017-10-03 at 09:24 +0200, Matthias Fischer wrote:
Hi,
On 03.10.2017 08:50, Matthias Fischer wrote:
...
Suddenly 'mc 4.8.19' starts throwing segfaults...
...
This is weird.
As soon as directory (e.g. '/usr/local/bin') contains the file 'ipfirereboot', 'mc' crashes while searching for content 'flush' (e.g.).
Thus, I would say, 'mc' has problems searching in (specific) binaries - searching in '/usr/bin' has the same effect.
And:
The following 'paxctl'-options had NO effect:
... root@ipfire: /usr/bin # paxctl -v /usr/bin/mc PaX control v0.9 Copyright 2004,2005,2006,2007,2009,2010,2011,2012,2014 PaX Team pageexec@freemail.hu
- PaX flags: -p-s-m-x-e-- [/usr/bin/mc] PAGEEXEC is disabled SEGMEXEC is disabled MPROTECT is disabled RANDEXEC is disabled EMUTRAMP is disabled
...
Searching in text-only files is ok, but as soon as directory contains the above file (or something similar), 'mc' crashes.
This does NOT happen on my devel with 'mc 4.8.15'... ;-)
Best, Matthias
On 04.10.2017 17:41, Michael Tremer wrote:
Hi,
Hello,
this doesn't have anything to do with PaX. It's just a bug in mc.
Probably has this problem with files that have the SUID bit set?!
Perhaps. Will look at this when I have the time again.
Did you try to update mc?
I tested with several versions and clean compilations - its always the same. On the 'Devel' machine (Ubuntu, mc 4.8.15, no PaX) everything works.
Best, Matthias
-Michael
On Tue, 2017-10-03 at 09:24 +0200, Matthias Fischer wrote:
Hi,
On 03.10.2017 08:50, Matthias Fischer wrote:
...
Suddenly 'mc 4.8.19' starts throwing segfaults...
...
This is weird.
As soon as directory (e.g. '/usr/local/bin') contains the file 'ipfirereboot', 'mc' crashes while searching for content 'flush' (e.g.).
Thus, I would say, 'mc' has problems searching in (specific) binaries - searching in '/usr/bin' has the same effect.
And:
The following 'paxctl'-options had NO effect:
... root@ipfire: /usr/bin # paxctl -v /usr/bin/mc PaX control v0.9 Copyright 2004,2005,2006,2007,2009,2010,2011,2012,2014 PaX Team pageexec@freemail.hu
- PaX flags: -p-s-m-x-e-- [/usr/bin/mc] PAGEEXEC is disabled SEGMEXEC is disabled MPROTECT is disabled RANDEXEC is disabled EMUTRAMP is disabled
...
Searching in text-only files is ok, but as soon as directory contains the above file (or something similar), 'mc' crashes.
This does NOT happen on my devel with 'mc 4.8.15'... ;-)
Best, Matthias
-
Matthias Fischer -
Michael Tremer