rwall adds \377 bytes to short messages

[Chris Good]

When sending from and receiving to Ubuntu 12.04.4 LTS :

Extra \377 bytes and a trailing '1' are included in the received message, when it is less than 11 characters long.

# echo 12345 | rwall HostName
Result:
12345
\377\377\377\377\3771

# echo 123456 | rwall HostName
Result:
123456
\377\377\377\3771

# echo 1234567 | rwall HostName
Result:
1234567
\377\377\3771

# echo 12345678 | rwall HostName
Result:
12345678
\377\3771

# echo 123456789 | rwall HostName
Result:
123456789
\3771

# echo 1234567890 | rwall HostName
Result:
1234567890
1

# echo 1234567890A | rwall HostName
Result:
1234567890A
(No extra characters for messages >= 11 chars long)

Source: netkit-rwall
Version: 0.17-7

# lsb_release -rd
Description: Ubuntu 12.04.4 LTS
Release: 12.04

# apt-cache policy rwall
rwall:
  Installed: 0.17-7
  Candidate: 0.17-7
  Version table:
 *** 0.17-7 0
        500 http://au.archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
        100 /var/lib/dpkg/status

[Chris Good (chris-good)]

I've worked out a patch to rwall.c which null terminates mbuf before it is passed to clnt_create().
This fixes the problem in precise (12.04.4).
However, when I test in trusty (14.04 Beta2), the problem does not exist in the original rwall & rpc.rwalld, even though rwall & rpc.rwalld are the same package version (0.17-7) and rwall & rpc.rwalld have the same 'sum -r' as precise.

Darn, I assumed that because they were the same, the problem needed to be fixed.
I wonder what else has changed that fixed the problem...

[Chris Good (chris-good)]

While the problem doesn't show on trusty, I still think it is a bug that should be fixed.
I've pushed my fix branch to :
https://code.launchpad.net/~chris-good/ubuntu/trusty/netkit-rwall/fix-for-1277981
and proposed a merge.
The trusty ppa is :
https://launchpad.net/~chris-good/+archive/rwall-ppa

[Chris Good (chris-good)]

debdiff

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "netkit-rwall-1277981.debdiff" seems to be a debdiff. The ubuntu-sponsors team has been subscribed to the bug report so that they can review and hopefully sponsor the debdiff. If the attachment isn't a patch, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are member of the ~ubuntu-sponsors, unsubscribe the team.

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

[Robie Basak (racb)]

Unsubscribing sponsors since I see that https://code.launchpad.net/~chris-good/ubuntu/trusty/netkit-rwall/fix-for-1277981/+merge/216563 already exists, and so this is causing this request to be in the sponsorship queue twice.

[Steve Langasek (vorlon)]

The Precise Pangolin has reached end of life, so this bug will not be fixed for that release