PERL5125DELTA(1) Perl Programmers Reference Guide PERL5125DELTA(1)
NAME
perl5125delta - what is new for perl v5.12.5
DESCRIPTION
This document describes differences between the 5.12.4 release and the
5.12.5 release.
If you are upgrading from an earlier release such as 5.12.3, first read
perl5124delta, which describes differences between 5.12.3 and 5.12.4.
Security
"Encode" decode_xs n-byte heap-overflow (CVE-2011-2939)
A bug in "Encode" could, on certain inputs, cause the heap to overflow.
This problem has been corrected. Bug reported by Robert Zacek.
File::Glob::bsd_glob() memory error with GLOB_ALTDIRFUNC (CVE-2011-2728)
Calling "File::Glob::bsd_glob" with the unsupported flag GLOB_ALTDIRFUNC
would cause an access violation / segfault. A Perl program that accepts
a flags value from an external source could expose itself to denial of
service or arbitrary code execution attacks. There are no known
exploits in the wild. The problem has been corrected by explicitly
disabling all unsupported flags and setting unused function pointers to
null. Bug reported by Clément Lecigne.
Heap buffer overrun in 'x' string repeat operator (CVE-2012-5195)
Poorly written perl code that allows an attacker to specify the count to
perl's 'x' string repeat operator can already cause a memory exhaustion
denial-of-service attack. A flaw in versions of perl before 5.15.5 can
escalate that into a heap buffer overrun; coupled with versions of glibc
before 2.16, it possibly allows the execution of arbitrary code.
This problem has been fixed.
Incompatible Changes
There are no changes intentionally incompatible with 5.12.4. If any
exist, they are bugs and reports are welcome.
Modules and Pragmata
Updated Modules
B::Concise
B::Concise no longer produces mangled output with the -tree option [perl
#80632].
charnames
A regression introduced in Perl 5.8.8 has been fixed, that caused
charnames::viacode(0) to return "undef" instead of the string "NULL"
[perl #72624].
Encode has been upgraded from version 2.39 to version 2.39_01
See "Security".
File::Glob has been upgraded from version 1.07 to version 1.07_01
See "Security".
Unicode::UCD
The documentation for the "upper" function now actually says "upper",
not "lower".
Module::CoreList
Module::CoreList has been updated to version 2.50_02 to add data for
this release.
Changes to Existing Documentation
perlebcdic
The perlebcdic document contains a helpful table to use in "tr///" to
convert between EBCDIC and Latin1/ASCII. Unfortunately, the table was
the inverse of the one it describes. This has been corrected.
perlunicode
The section on User-Defined Case Mappings had some bad markup and
unclear sentences, making parts of it unreadable. This has been
rectified.
perluniprops
This document has been corrected to take non-ASCII platforms into
account.
Installation and Configuration Improvements
Platform Specific Changes
Mac OS X
There have been configuration and test fixes to make Perl build
cleanly on Lion and Mountain Lion.
NetBSD
The NetBSD hints file was corrected to be compatible with NetBSD 6.*
Selected Bug Fixes
• "chop" now correctly handles characters above "\x{7fffffff}" [perl
#73246].
• "($<,$>) = (...)" stopped working properly in 5.12.0. It is
supposed to make a single setreuid() call, rather than calling
setruid() and seteuid() separately. Consequently it did not work
properly. This has been fixed [perl #75212].
• Fixed a regression of kill() when a match variable is used for the
process ID to kill [perl #75812].
• "UNIVERSAL::VERSION" no longer leaks memory. It started leaking in
Perl 5.10.0.
• The C-level "my_strftime" functions no longer leaks memory. This
fixes a memory leak in "POSIX::strftime" [perl #73520].
• "caller" no longer leaks memory when called from the DB package if
@DB::args was assigned to after the first call to "caller". Carp
was triggering this bug [perl #97010].
• Passing to "index" an offset beyond the end of the string when the
string is encoded internally in UTF8 no longer causes panics [perl
#75898].
• Syntax errors in "(?{...})" blocks in regular expressions no longer
cause panic messages [perl #2353].
• Perl 5.10.0 introduced some faulty logic that made "U*" in the
middle of a pack template equivalent to "U0" if the input string was
empty. This has been fixed [perl #90160].
Errata
split() and @_
split() no longer modifies @_ when called in scalar or void context. In
void context it now produces a "Useless use of split" warning. This is
actually a change introduced in perl 5.12.0, but it was missed from that
release's perl5120delta.
Acknowledgements
Perl 5.12.5 represents approximately 17 months of development since Perl
5.12.4 and contains approximately 1,900 lines of changes across 64 files
from 18 authors.
Perl continues to flourish into its third decade thanks to a vibrant
community of users and developers. The following people are known to
have contributed the improvements that became Perl 5.12.5:
Andy Dougherty, Chris 'BinGOs' Williams, Craig A. Berry, David Mitchell,
Dominic Hargreaves, Father Chrysostomos, Florian Ragwitz, George Greer,
Goro Fuji, Jesse Vincent, Karl Williamson, Leon Brocard, Nicholas Clark,
Rafael Garcia-Suarez, Reini Urban, Ricardo Signes, Steve Hay, Tony Cook.
The list above is almost certainly incomplete as it is automatically
generated from version control history. In particular, it does not
include the names of the (very much appreciated) contributors who
reported issues to the Perl bug tracker.
Many of the changes included in this version originated in the CPAN
modules included in Perl's core. We're grateful to the entire CPAN
community for helping Perl to flourish.
For a more complete list of all of Perl's historical contributors,
please see the AUTHORS file in the Perl source distribution.
Reporting Bugs
If you find what you think is a bug, you might check the articles
recently posted to the comp.lang.perl.misc newsgroup and the perl bug
database at http://rt.perl.org/perlbug/ . There may also be information
at http://www.perl.org/ , the Perl Home Page.
If you believe you have an unreported bug, please run the perlbug
program included with your release. Be sure to trim your bug down to a
tiny but sufficient test case. Your bug report, along with the output
of "perl -V", will be sent off to perlbug@perl.org to be analysed by the
Perl porting team.
If the bug you are reporting has security implications, which make it
inappropriate to send to a publicly archived mailing list, then please
send it to perl5-security-report@perl.org. This points to a closed
subscription unarchived mailing list, which includes all the core
committers, who be able to help assess the impact of issues, figure out
a resolution, and help co-ordinate the release of patches to mitigate or
fix the problem across all platforms on which Perl is supported. Please
only use this address for security issues in the Perl core, not for
modules independently distributed on CPAN.
SEE ALSO
The Changes file for an explanation of how to view exhaustive details on
what changed.
The INSTALL file for how to build Perl.
The README file for general stuff.
The Artistic and Copying files for copyright information.
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