[buildd-tools-devel] Bug#566879: Bug#566879: Bug#566879: Bug#566879: dchroot: does not work as root

[Roger Leigh]

On Thu, Jan 28, 2010 at 09:34:35PM +0000, Roger Leigh wrote:
> OK, I have a fix!  (attached)
[...]
> This has been committed into git, but I'll need to ponder the
> implications for a little bit before I upload it.

After further review:
the patch as presented (really attached this time) introduces a
security hole that while user->otheruser switching is forbidden,
user->user authentication will always succeed.  While there's no
hole *at present*, the altered semantics of auth_null could
result in a future bug if we make the assumption of failure.

Solution:
1) Keep auth_null as the default session authentication method.
2) Add auth_pam to *all* of schroot/dchroot/dchroot-dsa by
   adding add_session_auth to schroot::main_base (common to
   dchroot, dchroot-dsa and schroot).  Make virtual to allow
   addition of user-switching for schroot.

Mostly done, but won't be finished tonight.  Since this has
potential for security problems, I'll need to carefully
review it.


Regards,
Roger

-- 
  .''`.  Roger Leigh
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