Re: panic: attempt to copy freed scalar caused by calling cgi->param with TryCatch since perl 5.19.7

I use the Debian apreq package from apt, to install mod_perl, but the rest
of my dependencies I install through cpan
On Sep 16, 2015 9:33 AM, "Michael Schout" <[email protected]> wrote:

> On 9/16/15 7:08 AM, Vincent Veyron wrote:
>
> > I put your test handler on a machine running Debian 8 (jessie), it works
> just fine.
>
> Fails for me on both CentOS 7 and Darwin (OS X 10.10.5). I see you are
> using Apache 2.4 (I was using 2.2).  I tested with Apache 2.4.16 and it
> also fails for me on that as well
>
> Server version: Apache/2.4.16 (Unix)
> Server built:   Sep 16 2015 09:21:11
>
> I built perl myself to rule out vendor applied patches to the perl dist.
> I wonder if one of the many patches debian applies to perl works around
> this issue somehow.  Debian also applies a bunch of patches (18 as of
> current dpkg src) to the mod_perl package.  Maybe one of those works
> around the issue.  I'll sift through those patches and see if any of
> those help.
>
> Are you using debian packages for the CPAN modules at all?  Or did you
> install all CPAN packages using a CPAN client?  Because I also wonder if
> they patched TryCatch, Devel::Declare, or one of its dependencies to
> work around this issue.
>
> Here is the failure on CentOS 7, apache 2.4, perl 5.20.3, mod_perl
> 2.0.9, all built from scratch, no vendor packages used:
>
> [mschout@centos7 modperl-trycatch-bug]$ make test
> /home/mschout/perlbug/bin/perl -Iblib/arch -Iblib/lib \
> t/TEST  -clean
> [warning] setting ulimit to allow core files
> ulimit -c unlimited; /home/mschout/perlbug/bin/perl
> /home/mschout/modperl-trycatch-bug/t/TEST -clean
> APACHE_TEST_APXS= APACHE_TEST_GROUP= APACHE_TEST_HTTPD=
> APACHE_TEST_PORT= APACHE_TEST_USER= \
> /home/mschout/perlbug/bin/perl -Iblib/arch -Iblib/lib \
> t/TEST  -bugreport -verbose=0
> [warning] setting ulimit to allow core files
> ulimit -c unlimited; /home/mschout/perlbug/bin/perl
> /home/mschout/modperl-trycatch-bug/t/TEST -bugreport -verbose=0
> /home/mschout/perlbug/bin/httpd  -d /home/mschout/modperl-trycatch-bug/t
> -f /home/mschout/modperl-trycatch-bug/t/conf/httpd.conf -D APACHE2 -D
> APACHE2_4 -D PERL_USEITHREADS
> using Apache/2.4.16 (prefork MPM)
>
> waiting 60 seconds for server to start: ..
> waiting 60 seconds for server to start: ok (waited 1 secs)
> server localhost:8529 started
> t/crash.t .. Dubious, test returned 2 (wstat 512, 0x200)
> Failed 2/2 subtests
>
> t/logs/error_log
> [Wed Sep 16 09:27:19.394249 2015] [mpm_prefork:notice] [pid 4129]
> AH00163: Apache/2.4.16 (Unix) mod_perl/2.0.9 Perl/v5.20.3 configured --
> resuming normal operations
> [Wed Sep 16 09:27:19.394372 2015] [mpm_prefork:info] [pid 4129] AH00164:
> Server built: Sep 16 2015 09:21:11
> [Wed Sep 16 09:27:19.394381 2015] [core:notice] [pid 4129] AH00094:
> Command line: '/home/mschout/perlbug/bin/httpd -d
> /home/mschout/modperl-trycatch-bug/t -f
> /home/mschout/modperl-trycatch-bug/t/conf/httpd.conf -D APACHE2 -D
> APACHE2_4 -D PERL_USEITHREADS'
> [Wed Sep 16 09:27:19.394386 2015] [mpm_prefork:debug] [pid 4129]
> prefork.c(995): AH00165: Accept mutex: sysvsem (default: sysvsem)
> [Wed Sep 16 09:27:20.246297 2015] [authz_core:debug] [pid 4130]
> mod_authz_core.c(835): [client 127.0.0.1:46738] AH01628: authorization
> result: granted (no directives)
> [Wed Sep 16 09:27:20.498088 2015] [authz_core:debug] [pid 4130]
> mod_authz_core.c(835): [client 127.0.0.1:46739] AH01628: authorization
> result: granted (no directives)
> [Wed Sep 16 09:27:20.500796 2015] [perl:error] [pid 4130] [client
> 127.0.0.1:46739] panic: attempt to copy freed scalar 34259c0 to 3425870
> at /home/mschout/modperl-trycatch-bug/blib/lib/Apache/TryCatch.pm line
> 20.\n
> [Wed Sep 16 09:27:20.526382 2015] [core:info] [pid 4129] AH00096:
> removed PID file /home/mschout/modperl-trycatch-bug/t/logs/httpd.pid
> (pid=4129)
> [Wed Sep 16 09:27:20.526398 2015] [mpm_prefork:notice] [pid 4129]
> AH00169: caught SIGTERM, shutting down
>
>
>  But you are likely not seeing it because one of:
>
> - vendor patches applied by debian packaging team
> - you are using Apache 2.4.  I tested with Apache 2.2.
>
>
> Regards,
> Michael Schout
>