Motif library v4.0.4 causes segfault in legacy app

[Quang Ong]

Our group develops an X application that uses the Motif Library (package libxm4 v2.3.4-5). It appears that in the latest version of libXm.4.0.4 on Trusty (14.04), on certain types of X events, it causes a segfault. I've isolated this to a particular version of the library and OS rev. Our application works fine for OS older than 14.04, ie 12.04 etc. I also confirmed the version issue by copying libXm.4.0.3 from a 12.04 machine onto a 14.04 machine and it allows the program to work normally. I basically copied libXm.4.0.3 from a 12.04 machine to the 14.04 machine and created a symlink to it:
ln -s /usr/lib/x86_64-linux-gnu/libXm.4.0.3 /usr/lib/x86_64-linux-gnu/libXm.4.0.4

So, whatever has changed between 4.0.3 and 4.0.4 has broken some API calls. It's hard for us to debug this from the application side b/c it generates a segfault, which causes the application to crash.

Example of what causes the crash. When our application generates a child window which has text field widgets like a text field or textarea, typing into the field causes this crash.

Any ideas on why the new version would cause these crashes? Looking at the release notes (/usr/share/doc/libmotif-dev/RELNOTES.gz), I see there were a number of bug fixes. Is it possible one of these fixes caused another bug?
Thanks in advance.

Quang

[Sebastien Bacher (seb128)]

Could you get a backtrace of the issue using gdb?

[Graham Inggs (ginggs)]

Hi Quang

Thank you for reporting this.

This might be the same issue as LP: #1354961.

Please try this version from my PPA and report back:

https://launchpad.net/~ginggs/+archive/ubuntu/motif1565

Regards
Graham

[Quang Ong (quang777)]

Graham,
   thanks for the update. I'll give the fix a try and get back to you. I've only used gdb a couple of times. Are there instructions on how to use gdb to get a backtrace?

Q

[Quang Ong (quang777)]

I added the PPA to my test system and tried to fetch the updated package:
1) apt-get update
2) apt-get install motif failed
3) apt-get install motif-2.3.4-8 failed
4) apt-get install libmotif3 => updated to Preparing to unpack .../libmotif3_2.3.4-5_amd64.deb but from Ubuntu repo
5) apt-get install libmotif4 => also updated from Ubuntu repo version .../libmotif4_2.3.4-5_amd64.deb

What's the name of the patched package?

Q

[Graham Inggs (ginggs)]

After adding the PPA, you should only have to do:
apt-get update
apt-get upgrade

The packages are named libxm4, libmrm4, libuil4, as they are named in the Ubuntu repository.

[Quang Ong (quang777)]

I after I added the PPA, I see it added a file in /etc/apt/sources.list:
deb-src http://ppa.launchpad.net/ginggs/motif1565/ubuntu trusty main

 however it doesn't see updated packages for motif. Do I need to tell it to override the version that's installed from Ubuntu?

apt-get update
apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages have been kept back:
  linux-generic linux-headers-generic linux-image-generic
The following packages will be upgraded:
  apparmor apport apport-gtk bash-completion bind9-host bsdutils dnsutils
  e2fslibs e2fsprogs firefox gir1.2-gdkpixbuf-2.0 google-chrome-beta gvfs
  gvfs-backends gvfs-bin gvfs-common gvfs-daemons gvfs-fuse gvfs-libs
  irqbalance libapparmor-perl libapparmor1 libbind9-90 libblkid1 libcomerr2
  libdns100 libexpat1 libfreetype6 libgdk-pixbuf2.0-0 libgdk-pixbuf2.0-common
  libicu52 libisc95 libisccc90 libisccfg90 libldap-2.4-2 liblwres90 libmount1
  liboxideqt-qmlplugin liboxideqtcore0 liboxideqtquick0 libslp1 libsmbclient
  libsnmp-base libsnmp30 libspice-server1 libss2 libuuid1 libwbclient0
  linux-firmware linux-libc-dev mount onboard onboard-data openssh-client
  openssh-server openssh-sftp-server oxideqt-codecs python-samba
  python3-apport python3-problem-report samba-common samba-common-bin
  samba-libs smbclient ssh-askpass-gnome sudo thunderbird
  thunderbird-gnome-support tzdata unity-settings-daemon util-linux
  uuid-runtime xul-ext-ubufox
73 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.
Need to get 198 MB of archives.
After this operation, 9,118 kB of additional disk space will be used.

[Graham Inggs (ginggs)]

How did you add the PPA?

You should have the line as follows (i.e. without -src):

deb http://ppa.launchpad.net/ginggs/motif1565/ubuntu trusty main

You only need the deb-src line if you want to download the source packages as well.

[Quang Ong (quang777)]

Hmm, I ran
add-apt-repository ppa:ginggs/motif1565, which added this file:
/etc/apt/sources.list.d/ginggs-motif1565-trusty.list
with the following contents:
# deb-src http://ppa.launchpad.net/ginggs/motif1565/ubuntu trusty main

add-apt-repository ppa:ginggs/motif1565
 Motif built with upstream's fixes for bug #1565 [1] reverted.
Should behave as in Motif 2.3.3. and fix LP: #1354961 and LP: #1255473.

[1] http://bugs.motifzone.net/show_bug.cgi?id=1565
 More info: https://launchpad.net/~ginggs/+archive/ubuntu/motif1565
Press [ENTER] to continue or ctrl-c to cancel adding it

gpg: keyring `/tmp/tmp3fjgg8my/secring.gpg' created
gpg: keyring `/tmp/tmp3fjgg8my/pubring.gpg' created
gpg: requesting key 08CC41D2 from hkp server keyserver.ubuntu.com
gpg: /tmp/tmp3fjgg8my/trustdb.gpg: trustdb created
gpg: key 08CC41D2: public key "Launchpad PPA for Graham Inggs" imported
gpg: Total number processed: 1
gpg: imported: 1 (RSA: 1)
OK

Since I didn't see the updated packages, I uncommented the only line in
/etc/apt/sources.list.d/ginggs-motif1565-trusty.list

After re-running the steps again, this time it added to ginggs-motif1565-trusty.list:
deb http://ppa.launchpad.net/ginggs/motif1565/ubuntu trusty main

Looks like it worked this time:

 apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages have been kept back:
  libmotif-common libmotif-dev libmrm4 libuil4 libxm4 linux-generic
  linux-headers-generic linux-image-generic uil
The following packages will be upgraded:
  apparmor apport apport-gtk bash-completion bind9-host biosdevname bsdutils
  dnsutils e2fslibs e2fsprogs firefox gir1.2-gdkpixbuf-2.0 gir1.2-gudev-1.0
  google-chrome-beta gtk2-engines-pixbuf gvfs gvfs-backends gvfs-bin
  gvfs-common gvfs-daemons gvfs-fuse gvfs-libs irqbalance libapparmor-perl
  libapparmor1 libbind9-90 libblkid1 libcomerr2 libdns100 libexpat1
  libfreetype6 libgail-common libgail18 libgdk-pixbuf2.0-0
  libgdk-pixbuf2.0-common libgtk2.0-0 libgtk2.0-bin libgtk2.0-common
  libgudev-1.0-0 libicu52 libisc95 libisccc90 libisccfg90 libldap-2.4-2
  liblwres90 libmotif3 libmotif4 libmount1 liboxideqt-qmlplugin
  liboxideqtcore0 liboxideqtquick0 libpam-systemd libpython3.4
  libpython3.4-minimal libpython3.4-stdlib libslp1 libsmbclient libsnmp-base
  libsnmp30 libspice-server1 libss2 libsystemd-daemon0 libsystemd-journal0
  libsystemd-login0 libudev1 libufe-xidgetter0 libuuid1 libwbclient0
  linux-firmware linux-libc-dev lshw mount onboard onboard-data openssh-client
  openssh-server openssh-sftp-server oxideqt-codecs python-samba
  python3-apport python3-gdbm python3-problem-report python3.4
  python3.4-minimal samba-common samba-common-bin samba-libs smbclient
  ssh-askpass-gnome sudo systemd-services thunderbird
  thunderbird-gnome-support tzdata udev unity-settings-daemon util-linux
  uuid-runtime webaccounts-extension-common xul-ext-ubufox xul-ext-unity
  xul-ext-webaccounts xul-ext-websites-integration
103 upgraded, 0 newly installed, 0 to remove and 9 not upgraded.
Need to get 207 MB of archives.

Will test out these "new/old" versions and report back. Than...

[Quang Ong (quang777)]

I just realized that apt-get upgrade wasn't sufficient b/c it warns that the packages I need updated will be held back:
The following packages have been kept back:
  libmotif-common libmotif-dev libmrm4 libuil4 libxm4 linux-generic

I had to do:
apt-get dist-upgrade
The following packages will be upgraded:
  libmotif-common libmotif-dev libmrm4 libuil4 libxm4 linux-generic

After this, I do see the updated motif library (dated March-2015 vs 2013):
ls -l /usr/lib/x86_64-linux-gnu/libXm.so.4.0.4
-rw-r--r-- 1 root root 2837728 Mar 24 2015 /usr/lib/x86_64-linux-gnu/libXm.so.4.0.4

Using my test case, it no longer causes a segfault. I'll do some more testing but it looks like this fixed it.
Any chance this update will get pushed into the official Ubuntu updates?

Thanks!

[Graham Inggs (ginggs)]

> Using my test case, it no longer causes a segfault. I'll do some more testing
> but it looks like this fixed it.

Glad to hear it!

> Any chance this update will get pushed into the official Ubuntu updates?

Yes, I will start the SRU process.