Re: Segfault in PerlModule with PAR.pm

Nathan Byrd wrote:
> Hi all,
>
> I have been getting a segfault when starting mod_perl 2.x under rather
> unusual circumstances.  Hopefully the below bug report will be useful,
> although I'm not sure whether the problem lies in mod_perl 2.x or PAR.pm
> (a CPAN module), but since the entire trace from debugging was in
> mod_perl 2.x code, I thought I'd start here.  Please let me know if
> there is any other information I can provide that would be helpful.

It's a mod_perl problem.

> Program received signal SIGSEGV, Segmentation fault.
> 0x4032dcf7 in modperl_cmd_modules (parms=0xbfffeae0, mconfig=0x80c6fc0,
>     arg=0x83dc268 "TestMod") at modperl_cmd.c:95
> 95              dTHXa(scfg->mip->parent->perl);

most likely it dereferences a NULL pointer.

> -------------8<---------- Start Bug Report ------------8<----------
> 1. Problem Description:
>
> Currently I'm getting a segmentation fault when starting mod_perl 2.x
> (CVS)  This happens when doing the following steps:
>
> Module is loaded via PerlModule (Apache::PAR).  That module then adds
> configuration via Apache->httpd_conf($conf). 

Unrelated to the reported problem, but please don't use Apache::compat in CPAN 
modules. Apache->httpd_conf is in compat.pm

> If the configuration being
> added contains a PerlModule line for a module which is loaded via the
> PAR CPAN module, I get the below trace.
>
> The configuration which is sent to Apache->httpd_conf is:
>
> Alias /test/module/ /home/techy/cvs/apache-par/t/par/module.par/
> PerlModule TestMod
> <Location /test/module>
> SetHandler perl-script
> PerlHandler TestMod
> </Location>
>
> I can't seem to duplicate this with other PerlModule lines included via
> httpd_conf() other than ones for modules which are loaded via the PAR
> module.  Further, if I leave out the PerlModule line, the rest of the
> configuration works ok (and the module runs correctly)  It does not
> appear to matter what the contents of TestMod.pm are.

That's becase scfg->mip->parent->perl is set later on.

Are you using a vhost for this section?

Any chance you can come up with a stripped version of Apache::PAR that still 
reproduces the problem? So we can have a good test?

If not, where do I get the version of Apache::PAR that you are having the 
problem with?

__________________________________________________________________
Stas Bekman            JAm_pH ------> Just Another mod_perl Hacker
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