rpms/perl
7
0
Fork 0
Code Issues Pull Requests Releases Activity

Fix dead lock in PerlIO after fork from thread

Browse Source
This commit is contained in:
Petr Písař 2013-04-10 15:37:36 +02:00
parent c367bfcf00
commit a381049bf6
2 changed files with 54 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
perl-5.17.9-106212-Add-PL_perlio_mutex-to-atfork_lock.patch Normal file
View File

@ -0,0 +1,48 @@
From 4da80956418bbe1fdc23cad0b1cbb24cd7b87609 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Patrik=20H=C3=A4gglund?= <patrik.h.hagglund@ericsson.com>
Date: Sat, 2 Feb 2013 20:21:05 +0100
Subject: [PATCH] PATCH [perl #106212] Add PL_perlio_mutex to
atfork_lock/unlock
Using threads + fork() on Linux, and IO operations in the threads, the
PL_perlio_mutex may be left in a locked state at the call of fork(),
potentially leading to deadlock in the child process at subsequent IO
operations. (Threads are pre-empted and not continued in the child
process after the fork.)
Therefore, ensure that the PL_perlio_mutex is unlocked in the child
process, right after fork(), by using atfork_lock/unlock.
(The RT text gives ways to reproduce the problem, but are not easily
added to Perl's test suite)
---
util.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/util.c b/util.c
index 5c695b8..75381f1 100644
--- a/util.c
+++ b/util.c
@@ -2798,6 +2798,9 @@ Perl_atfork_lock(void)
dVAR;
#if defined(USE_ITHREADS)
/* locks must be held in locking order (if any) */
+# ifdef USE_PERLIO
+ MUTEX_LOCK(&PL_perlio_mutex);
+# endif
# ifdef MYMALLOC
MUTEX_LOCK(&PL_malloc_mutex);
# endif
@@ -2812,6 +2815,9 @@ Perl_atfork_unlock(void)
dVAR;
#if defined(USE_ITHREADS)
/* locks must be released in same order as in atfork_lock() */
+# ifdef USE_PERLIO
+ MUTEX_UNLOCK(&PL_perlio_mutex);
+# endif
# ifdef MYMALLOC
MUTEX_UNLOCK(&PL_malloc_mutex);
# endif
--
1.8.1.4

6
perl.spec
View File

@ -119,6 +119,9 @@ Patch22: perl-5.16.3-Don-t-leak-deleted-iterator-when-tying-hash.patch
Patch23: perl-5.16.3-Free-iterator-when-freeing-tied-hash.patch
Patch24: perl-5.16.3-Don-t-leak-if-hh-copying-dies.patch
# Fix dead lock in PerlIO after fork from thread, rhbz#947444, RT#106212
Patch25: perl-5.17.9-106212-Add-PL_perlio_mutex-to-atfork_lock.patch
# Update some of the bundled modules
# see http://fedoraproject.org/wiki/Perl/perl.spec for instructions
@ -1830,6 +1833,7 @@ tarball from perl.org.
%patch22 -p1
%patch23 -p1
%patch24 -p1
%patch25 -p1
#copy the example script
cp -a %{SOURCE5} .
@ -2044,6 +2048,7 @@ pushd %{build_archlib}/CORE/
'Fedora Patch22: Fix leaking tied hashes (RT#107000) [1]' \
'Fedora Patch23: Fix leaking tied hashes (RT#107000) [2]' \
'Fedora Patch24: Fix leaking tied hashes (RT#107000) [3]' \
'Fedora Patch25: Fix dead lock in PerlIO after fork from thread (RT106212)' \
%{nil}
rm patchlevel.bak
@ -3485,6 +3490,7 @@ sed \
%changelog
* Wed Apr 10 2013 Petr Pisar <ppisar@redhat.com> - 4:5.16.3-270
- Fix leaking tied hashes (bug #859910)
- Fix dead lock in PerlIO after fork from thread (bug #947444)
* Tue Apr 09 2013 Petr Pisar <ppisar@redhat.com> - 4:5.16.3-269
- Sub-package Sys-Syslog (bug #950057)