isenkram-lookup crashed with SIGSEGV in g_type_check_instance_cast()

[Gunnar Hjalmarsson]

[Impact]

An attempt to run the isenkram-lookup command from the isenkram-cli package results in a segfault/crash. The proposed appstream upload in <https://launchpad.net/~gunnarhj/+archive/ubuntu/appstream> fixes the issue.

[Test case]

1. Install the isenkram package

2. Run the isenkram-lookup command

-> Find that it segfaults

3. Install the packages built by the appstream source
   package from groovy-proposed

-> Find that the command succeeds and possibly lists a few
   suggested packages.

[Where problems could occur]

TBH this fix is far above my head. Only code comments are changed, i.e. some occurrences of "full" are replaced with "container", but it still has proved to be it.

The reasoning in the commit message sounds plausible:

https://github.com/ximion/appstream/commit/b52858bf

[Original description]

I just run the isenkram-lookup command.

The crash may be related to this autopkgtest failure (which current blocks migration of gtk+3.0):

https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-hirsute/hirsute/amd64/i/isenkram/20201108_141822_ee8c4@/log.gz

This is the script which fails:

https://salsa.debian.org/debian/isenkram/-/blob/master/debian/tests/test-command-line

and it includes the isenkram-lookup command.

ProblemType: Crash
DistroRelease: Ubuntu 21.04
Package: isenkram-cli 0.44
ProcVersionSignature: Ubuntu 5.8.0-25.26-generic 5.8.14
Uname: Linux 5.8.0-25-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu51
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Mon Nov 9 18:07:47 2020
ExecutablePath: /usr/bin/isenkram-lookup
ExecutableTimestamp: 1595665183
InstallationDate: Installed on 2019-11-10 (365 days ago)
InstallationMedia: Ubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017)
InterpreterPath: /usr/bin/python3.8
PackageArchitecture: all
ProcCmdline: /usr/bin/python3 /usr/bin/isenkram-lookup
ProcCwd: /home/gunnar
Python3Details: /usr/bin/python3.8, Python 3.8.6, python3-minimal, 3.8.6-0ubuntu1
PythonDetails: N/A
SegvAnalysis:
 Segfault happened at: 0x7f27ae221cca <g_type_check_instance_cast+26>: mov (%rdi),%rax
 PC (0x7f27ae221cca) ok
 source "(%rdi)" (0x6465737500000000) not located in a known VMA region (needed readable region)!
 destination "%rax" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: isenkram
StacktraceTop:
 g_type_check_instance_cast () at /lib/x86_64-linux-gnu/libgobject-2.0.so.0
 as_component_get_provided_for_kind () at /lib/x86_64-linux-gnu/libappstream.so.4
 () at /lib/x86_64-linux-gnu/libffi.so.8
 () at /lib/x86_64-linux-gnu/libffi.so.8
 () at /usr/lib/python3/dist-packages/gi/_gi.cpython-38-x86_64-linux-gnu.so
Title: isenkram-lookup crashed with SIGSEGV in g_type_check_instance_cast()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lp lpadmin lxd plugdev sambashare sudo
separator:

[Gunnar Hjalmarsson (gunnarhj)]

The isenkram-lookup command fails with a segfault also on Debian testing, so the problem is not Ubuntu specific.

[Gunnar Hjalmarsson (gunnarhj)]

The autopkgtest failure in Ubuntu fixed for now:

https://git.launchpad.net/~ubuntu-release/britney/+git/hints-ubuntu/commit/?id=0c1206e6

[Apport retracing service (apport)]

StacktraceTop:
 g_type_check_instance_cast (type_instance=type_instance@entry=0x6465737500000000, iface_type=34876208) at ../../../gobject/gtype.c:4053
 AS_PROVIDED (ptr=0x6465737500000000) at ../src/as-provided.h:33
 as_component_get_provided_for_kind (cpt=<optimized out>, kind=AS_PROVIDED_KIND_MODALIAS) at ../src/as-component.c:1685
 ffi_call_unix64 () at ../src/x86/unix64.S:106
 ffi_call_int (cif=<optimized out>, fn=<optimized out>, rvalue=<optimized out>, avalue=<optimized out>, closure=<optimized out>) at ../src/x86/ffi64.c:669

[Gunnar Hjalmarsson (gunnarhj)]

This has proved to be an appstream issue.

[Gunnar Hjalmarsson (gunnarhj)]

The PPA proposal has proved to be problematic:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=974107#83

So no solution in sight at the moment.

[Matthias Klumpp (ximion)]

The bug is actually this one, in gobject-introspection: https://gitlab.gnome.org/GNOME/gobject-introspection/-/issues/305

[Gunnar Hjalmarsson (gunnarhj)]

Fixed in appstream 0.13.1-1

[Matthias Klumpp (ximion)]

Not really fixed, AppStream has an incomplete workaround for the gobject-introspection bug (which may break at any time for new functions in either Python or Vala, if we aren't super careful).

[Gunnar Hjalmarsson (gunnarhj)]

Ok, Matthias, added a gobject-introspection bug task.