openssh unix dev - Feb 2016 - PubkeyAcceptedKeyTypes with + in Match block not working correctly.

Hello,

I notice that if I configure sshd_config with:

PubkeyAcceptedKeyTypes +ssh-dss

Everything  works as  expected  and  the algorithm  is  appended to  the
default list, but if  I place that same option in a  Match block it does
not extend the setting, but instead replaces it with a literal string of
``+ssh-dss'' which effectively disables all algorithms.

# tail -2 /etc/ssh/sshd_config
Match Address 192.168.1.0/24
  PubkeyAcceptedKeyTypes +ssh-dss

# sshd -T -C
user=tester,host=example.dom,addr=192.168.1.1,laddr=192.168.1.2,lport=22 | grep
pubkey
pubkeyauthentication yes
pubkeyacceptedkeytypes +ssh-dss

I found a similar bug  mentioned here regarding HostkeyAlgorithms but as
far as  I can tell  the fix didn't extend  to cover the  above mentioned
scenario:

http://marc.info/?l=openssh-unix-dev&m=144019508104294&w=2

Does this need to go reported also to bugs@ or is this list sufficient?

Thanks,

Andy
-- 
TAI64 timestamp: 4000000056b97aa2

On Tue, 8 Feb 2016, Andy Bradford wrote:
> Hello,
> 
> I notice that if I configure sshd_config with:
> 
> PubkeyAcceptedKeyTypes +ssh-dss
> 
> Everything  works as  expected  and  the algorithm  is  appended to  the
> default list, but if  I place that same option in a  Match block it does
> not extend the setting, but instead replaces it with a literal string of
> ``+ssh-dss'' which effectively disables all algorithms.
This was fixed in commit ed08510d38 and will be in openssh-7.2, which
is due real soon now (~weeks).

https://anongit.mindrot.org/openssh.git/commit/?id=ed08510d38

-d