Re: t5539 fails on ubuntu for v2.0.0-rc2

From: Jeff King <peff@peff.net>
Date: May 9, 2014, 15:59 UTC
Message-ID: <20140509155945.GG18197@sigill.intra.peff.net>
In-Reply-To: <536B1DF4.5080109@fabiodalfonso.com>

On Thu, May 08, 2014 at 08:02:28AM +0200, Fabio D'Alfonso wrote:

Show 16 quoted lines

> this is the error in httpd error.log
> 
>  [Wed May 07 20:44:10 2014] [alert] getpwuid: couldn't determine user name
> from  uid 4294967295, you probably need to modify the User directive
>  [Wed May 07 20:44:10 2014] [notice] Apache/2.2.17 (Ubuntu) configured --
> resuming normal operations
>  [Wed May 07 20:44:10 2014] [alert] getpwuid: couldn't determine user name
> from  uid 4294967295, you probably need to modify the User directive
>  [Wed May 07 20:44:10 2014] [alert] getpwuid: couldn't determine user name
> from  uid 4294967295, you probably need to modify the User directive
>  [Wed May 07 20:44:10 2014] [alert] getpwuid: couldn't determine user name
> from  uid 4294967295, you probably need to modify the User directive
>  [Wed May 07 20:44:10 2014] [alert] getpwuid: couldn't determine user name
> from  uid 4294967295, you probably need to modify the User directive
>  [Wed May 07 20:44:11 2014] [alert] Child 12037 returned a Fatal error...
> Apache is exiting!

Hmm.  Some googling turned up a similar case:

  http://www.linuxquestions.org/questions/linux-server-73/apache-won%27t-start-because-490312/

It looks like apache is trying to getpwuid (probably as part of doing a setuid on its children), failing, and then crashing. I suspect that this is related to you running as root, as a non-root apache would not want to (nor be able to) call setuid.

Does running the tests as a non-root user fix it? If so, I think we have a few options in git:

  1. Add a User directive to our httpd.conf. I doubt this is a good
     idea to do unconditionally, as a non-root apache would probably be
     unhappy with it.

  2. Add a User directive when we detect that the tests are running as
     root.  This might work, but I'm a bit iffy, as we do not know the
     appropriate username for the system (e.g., "nobody" versus
     "www-data" versus something else).

  3. Just disable the http tests when run as root.

I think I'd favor 3. But I'd like to be sure that being root is the problem.

-Peff