[apparmor] [PATCH 20/31] parser: Remove prints and exits from features code

[Christian Boltz]

Hello,

Am Donnerstag, 22. Januar 2015 schrieb Steve Beattie:
> On Thu, Jan 22, 2015 at 04:23:00PM -0600, Tyler Hicks wrote:
> > We don't know what a program linking to libapparmor will do with
> > stdout/stderr so I don't know if debug logging to those streams is
> > helpful.

stderr doesn't sound too bad, but might be lost in some situations (like 
starting a program via its desktop icon)

> > Maybe in the near future we could add a debug build option to
> > libapparmor and have it support an env variable that specifies a
> > file
> > path to open and log debug messages to?
> 
> That would be a very nice improvement indeed.

Would it also be a secure improvement? ;-)

Basically that feature would allow to overwrite any file if an attacker 
is able to inject an environment variable...

Possible options IMHO:
- random file names via mktemp (optionally using the env var as 
  template)
- hardcoded log path /var/log/apparmor/libapparmor, and loglevel set
  via env vars (that's what the utils do, BTW)
- use syslog


Regards,

Christian Boltz
-- 
Alles wird gut. Nichts wird besser. :-)
[Ratti in fontlinge-devel]