apport-collect permission error on retrieving boot.log

[Mike Ferreira]

RE: Bug Report: https://bugs.launchpad.net/ubuntu/+source/plymouth/+bug/2041736

While reviewing this Bug Report, to add a comment to help explain something for this user, i noticed this error from apport collect:
...
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
...

This file is needed by Launchpad for diagnostics.

Just this week, I helped a Forum user review his boot.log files, so I am familiar with this. The permissions and ownership of the boot.log.X files are currently:
mafoelffen@Mikes-B460M:~$ ls -l /var/log/boot*
-rw------- 1 root root 0 Oct 16 00:00 /var/log/boot.log
-rw------- 1 root root 101106 Oct 16 00:00 /var/log/boot.log.1
-rw------- 1 root root 50432 Oct 14 00:00 /var/log/boot.log.2
-rw------- 1 root root 201696 Oct 12 00:00 /var/log/boot.log.3
-rw------- 1 root root 50375 Oct 10 00:00 /var/log/boot.log.4
-rw------- 1 root root 50497 Oct 9 00:00 /var/log/boot.log.5
-rw------- 1 root root 1598 Sep 29 00:00 /var/log/boot.log.6
-rw------- 1 root root 26496 Sep 28 19:10 /var/log/boot.log.7
-rw-r--r-- 1 root root 108494 Apr 19 2022 /var/log/bootstrap.log
...
Which means the 'root' is only user that can open or view them.

Examples:
...
mafoelffen@Mikes-ThinkPad-T520:~/Downloads$ awk 'NR>3{exit} {print $0}' /var/log/boot.log
awk: fatal: cannot open file `/var/log/boot.log' for reading: Permission denied

mafoelffen@Mikes-ThinkPad-T520:~/Downloads$ sudo awk 'NR>3{exit} {print $0}' /var/log/boot.log
------------ Sat Jul 22 00:27:04 PDT 2023 ------------
[ OK ] Started Show Plymouth Boot Screen.
[ OK ] Started Forward Password R…s to Plymouth Directory Watch.
...

That is why I think apport-collect is getting permissions errors and failing to retrieve the user boot.log for upload.

Expected behavior:
apport-collect should upload the boot.log successfully.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: apport 2.20.11-0ubuntu82.5
ProcVersionSignature: Ubuntu 6.2.0-33.33~22.04.1-generic 6.2.16
Uname: Linux 6.2.0-33-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.11-0ubuntu82.5
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: GNOME
Date: Sat Oct 28 20:44:58 2023
InstallationDate: Installed on 2021-09-23 (765 days ago)
InstallationMedia: Ubuntu 20.04.3 LTS "Focal Fossa" - Release amd64 (20210819)
PackageArchitecture: all
SourcePackage: apport
UpgradeStatus: Upgraded to jammy on 2022-08-17 (438 days ago)

[Benjamin Drung (bdrung)]

I have not found boot.log in the apport source code, but it is mentioned two package hooks:

grep boot.log /usr/share/apport/ -r
/usr/share/apport/package-hooks/source_xorg.py: attach_file_if_exists(report, '/var/log/boot.log', 'BootLog')
/usr/share/apport/package-hooks/source_xorg.py: report['xserver.logfile'] = xlog.boot_logfile
/usr/share/apport/package-hooks/source_plymouth.py: attach_file(report, '/var/log/boot.log', 'BootLog')

They use attach_file or attach_file_if_exists. They need to use root_command_output instead.