"Release" files being overwritten on hotel etc networks

[David Henningsson]

I'm quite sure I'm not alone on seeing this, so this might be a duplicate of another bug. Nonetheless, it's quite annoying.

Sometimes when I travel with my laptop, files such as /var/lib/apt/lists/archive.canonical.com_ubuntu_dists_precise_Release become overwritten with data from the "hotel network". See attached file for what it currently looks like.

This results in apt-get update getting the following error message:

W: GPG error: http://archive.canonical.com precise Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key <email address hidden>

The workaround is to remove the offending _Release files.

So 1) why are these "Release" files just saved without any sanity checking, and 2) if they are, why isn't the correct file overwriting the wrong one now that I'm home again and on a sane network?

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: apt 0.8.16~exp12ubuntu10.2
ProcVersionSignature: Ubuntu 3.2.0-29.46-generic 3.2.24
Uname: Linux 3.2.0-29-generic x86_64
ApportVersion: 2.0.1-0ubuntu12
Architecture: amd64
Date: Tue Sep 18 15:15:57 2012
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120103)
SourcePackage: apt
UpgradeStatus: No upgrade log present (probably fresh install)