[perl] Do not access freed memory when cloning thread

[Petr Pisar]

commit d0fe0a83844ac75ba53dc258592a95d0101ecc30
Author: Petr Písař <ppisar at redhat.com>
Date:   Tue Sep 11 09:44:49 2012 +0200

    Do not access freed memory when cloning thread

 ...-Trouble-with-XS-APItest-t-clone-with-sta.patch |   56 ++++++++++++++++++++
 perl.spec                                          |   10 +++-
 2 files changed, 65 insertions(+), 1 deletions(-)
---
diff --git a/perl-5.16.1-perl-111610-Trouble-with-XS-APItest-t-clone-with-sta.patch b/perl-5.16.1-perl-111610-Trouble-with-XS-APItest-t-clone-with-sta.patch
new file mode 100644
index 0000000..f3d9fda
--- /dev/null
+++ b/perl-5.16.1-perl-111610-Trouble-with-XS-APItest-t-clone-with-sta.patch
@@ -0,0 +1,56 @@
+From 4a808ed163df1057031bc6d085300fe1ef6f57d2 Mon Sep 17 00:00:00 2001
+From: Michael Schroeder <mls at suse.de>
+Date: Fri, 8 Jun 2012 20:29:54 -0700
+Subject: [PATCH] [perl #111610] Trouble with XS-APItest/t/clone-with-stack.t
+
+I ran into a bit of a problem when building perl-5.16.0.
+'make test' showed a segfault in ext/XS-APItest/t/clone-with-stack.t.
+It seems to be caused by accessing already freed memory, it
+segfaults because I have MALLOC_PERTUBE_ set, thus glibc fills
+freed memory with some value.
+
+Digging deeper, it seems like perl_clone() does not fix
+the cx's blk_oldcop element when doing context cloning, thus
+blk_oldcop still points to PL_compiling in the old interp--the
+calling scope for the BEGIN block being the compilation of the
+code surrounding it--and the POPBLOCK done in leavesub will copy
+the data from the old interp to PL_curcop.
+
+After fixing this, it still crashed because interp_dup->Iop was
+zero after the runops_standard() call (which is probably
+correct as the end of the BEGIN block was reached). So I
+also added an if statement that checks the pointer.
+---
+ ext/XS-APItest/APItest.xs | 3 ++-
+ sv.c                      | 1 +
+ 2 files changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/ext/XS-APItest/APItest.xs b/ext/XS-APItest/APItest.xs
+index 2c0ee61..69b7066 100644
+--- a/ext/XS-APItest/APItest.xs
++++ b/ext/XS-APItest/APItest.xs
+@@ -3084,7 +3084,8 @@ CODE:
+     PERL_SET_CONTEXT(interp_dup);
+ 
+     /* continue after 'clone_with_stack' */
+-    interp_dup->Iop = interp_dup->Iop->op_next;
++    if (interp_dup->Iop)
++	interp_dup->Iop = interp_dup->Iop->op_next;
+ 
+     /* run with new perl */
+     Perl_runops_standard(interp_dup);
+diff --git a/sv.c b/sv.c
+index 2034c00..fcd76a9 100644
+--- a/sv.c
++++ b/sv.c
+@@ -12312,6 +12312,7 @@ Perl_cx_dup(pTHX_ PERL_CONTEXT *cxs, I32 ix, I32 max, CLONE_PARAMS* param)
+ 	    Perl_croak(aTHX_ "Cloning substitution context is unimplemented");
+ 	}
+ 	else {
++	    ncx->blk_oldcop = (COP*)any_dup(ncx->blk_oldcop, param->proto_perl);
+ 	    switch (CxTYPE(ncx)) {
+ 	    case CXt_SUB:
+ 		ncx->blk_sub.cv		= (ncx->blk_sub.olddepth == 0
+-- 
+1.7.11.4
+
diff --git a/perl.spec b/perl.spec
index 1bcd434..0eb69f3 100644
--- a/perl.spec
+++ b/perl.spec
@@ -29,7 +29,7 @@
 Name:           perl
 Version:        %{perl_version}
 # release number must be even higher, because dual-lived modules will be broken otherwise
-Release:        232%{?dist}
+Release:        233%{?dist}
 Epoch:          %{perl_epoch}
 Summary:        Practical Extraction and Report Language
 Group:          Development/Languages
@@ -82,6 +82,9 @@ Patch9:         perl-5.14.2-find2perl-transtate-question-mark-properly.patch
 # Fix broken atof, rhbz#835452, RT#109318
 Patch10:        perl-5.16.0-fix-broken-atof.patch
 
+# Do not access freed memory when cloning thread, rhbz#825749, RT#111610
+Patch11:        perl-5.16.1-perl-111610-Trouble-with-XS-APItest-t-clone-with-sta.patch
+
 # Fix searching for Unicode::Collate::Locale data, rhbz#756118, CPANRT#72666,
 # fixed in Unicode-Collate-0.87.
 # TODO Looks like it was fixed differently?
@@ -1319,6 +1322,7 @@ tarball from perl.org.
 %patch8 -p1
 %patch9 -p1
 %patch10 -p1
+%patch11 -p1
 
 #copy the example script
 cp -a %{SOURCE5} .
@@ -1521,6 +1525,7 @@ pushd %{build_archlib}/CORE/
     'Fedora Patch7: Dont run one io test due to random builder failures' \
     'Fedora Patch9: Fix find2perl to translate ? glob properly (RT#113054)' \
     'Fedora Patch10: Fix broken atof (RT#109318)' \
+    'Fedora Patch11: Do not access freed memory when cloning thread (RT#111610)' \
     %{nil}
 
 rm patchlevel.bak
@@ -2632,6 +2637,9 @@ sed \
 
 # Old changelog entries are preserved in CVS.
 %changelog
+* Tue Sep 11 2012 Petr Pisar <ppisar at redhat.com> - 4:5.16.1-233
+- Do not access freed memory when cloning thread (bug #825749)
+
 * Wed Sep 05 2012 Petr Pisar <ppisar at redhat.com> - 4:5.16.1-232
 - Move App::Cpan from perl-Test-Harness to perl-CPAN (bug #854577)