linux.sh processes empty/missing subinterface file

[Russell Phillips]

After upgrading from 12.04 to 14.04, I noticed that gogoc no longer started. I tracked it down to a logical error in the bash script to build the tunnel.

The following line appears 3 times in /usr/share/gogoc/template/linux.sh (lines 167, 279 and 312):

echo "$subif" | while read sub int ; do

It needs to first test that $subif is not empty.

When the subinterfaces file (/etc/gogoc/interfaces.conf) is empty or missing, the subif variable has an empty value.

What is happening, is that the radvd config file is populated with a second interface containing uninitialized nonsense, and radvd in turn fails to parse the config file. Radvd will then return an error status and gogoc will react by tearing down the tunnel.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "gogoc-bug.patch" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[John S. Gruber (jsjgruber)]

I tested Russel's patch and it worked for me (after I created the /var/run/gogoc/ directory by hand).

Good work, Russel.

[John S. Gruber (jsjgruber)]

I think this is a regression due to debian bug #651251.

It might help this bug along if you sent your patch to <email address hidden> to add it as a comment to that Debian bug. A reference to this bug report might help tie things together.

Before you do that you might check that bug at https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=731256 to see if you agree with me that it is the same bug you are reporting here.

[Russell Phillips (ignissport)]

John,

That looks exactly like what I saw. You can see it in his log where "Adding prefix" is repeated, but the second interface contains a null name and IPv6 address:

2013/12/03 23:03:28 I gogoc: Adding prefix to wlan0
2013/12/03 23:03:28 I gogoc: /sbin/ifconfig wlan0 add 2001:05c0:1506:de00::1/64
2013/12/03 23:03:28 I gogoc: Adding prefix to
2013/12/03 23:03:28 I gogoc: /sbin/ifconfig inet6 add ::1/64

I replied to the bug and pasted a URL to point back to here.

[menner (menner)]

patch fixes the problem on utopic