Ubuntu Manpage: perl5261delta - what is new for perl v5.26.1

Provided by: perl-doc_5.36.0-9ubuntu1.1_all

NAME

       perl5261delta - what is new for perl v5.26.1

DESCRIPTION

       This document describes differences between the 5.26.0 release and the 5.26.1 release.

       If you are upgrading from an earlier release such as 5.24.0, first read perl5260delta,
       which describes differences between 5.24.0 and 5.26.0.

Security

   [CVE-2017-12837] Heap buffer overflow in regular expression compiler
       Compiling certain regular expression patterns with the case-insensitive modifier could
       cause a heap buffer overflow and crash perl.  This has now been fixed.  [GH #16021]
       <https://github.com/Perl/perl5/issues/16021>

   [CVE-2017-12883] Buffer over-read in regular expression parser
       For certain types of syntax error in a regular expression pattern, the error message could
       either contain the contents of a random, possibly large, chunk of memory, or could crash
       perl.  This has now been fixed.  [GH #16025] <https://github.com/Perl/perl5/issues/16025>

   [CVE-2017-12814] $ENV{$key} stack buffer overflow on Windows
       A possible stack buffer overflow in the %ENV code on Windows has been fixed by removing
       the buffer completely since it was superfluous anyway.  [GH #16051]
       <https://github.com/Perl/perl5/issues/16051>

Incompatible Changes

       There are no changes intentionally incompatible with 5.26.0.  If any exist, they are bugs,
       and we request that you submit a report.  See "Reporting Bugs" below.

Modules and Pragmata

   Updated Modules and Pragmata
       •   base has been upgraded from version 2.25 to 2.26.

           The effects of dotless @INC on this module have been limited by the introduction of a
           more refined and accurate solution for removing '.' from @INC while reducing the false
           positives.

       •   charnames has been upgraded from version 1.44 to 1.45.

       •   Module::CoreList has been upgraded from version 5.20170530 to 5.20170922_26.

Platform Support

   Platform-Specific Notes
       FreeBSD
           •   Building with g++ on FreeBSD-11.0 has been fixed.  [GH #15984]
               <https://github.com/Perl/perl5/issues/15984>

       Windows
           •   Support for compiling perl on Windows using Microsoft Visual Studio 2017
               (containing Visual C++ 14.1) has been added.

           •   Building XS modules with GCC 6 in a 64-bit build of Perl failed due to incorrect
               mapping of "strtoll" and "strtoull".  This has now been fixed.  [GH #16074]
               <https://github.com/Perl/perl5/issues/16074> [cpan #121683]
               <https://rt.cpan.org/Public/Bug/Display.html?id=121683> [cpan #122353]
               <https://rt.cpan.org/Public/Bug/Display.html?id=122353>

Selected Bug Fixes

       •   Several built-in functions previously had bugs that could cause them to write to the
           internal stack without allocating room for the item being written.  In rare
           situations, this could have led to a crash.  These bugs have now been fixed, and if
           any similar bugs are introduced in future, they will be detected automatically in
           debugging builds.  [GH #16076] <https://github.com/Perl/perl5/issues/16076>

       •   Using a symbolic ref with postderef syntax as the key in a hash lookup was yielding an
           assertion failure on debugging builds.  [GH #16029]
           <https://github.com/Perl/perl5/issues/16029>

       •   List assignment ("aassign") could in some rare cases allocate an entry on the mortal
           stack and leave the entry uninitialized.  [GH #16017]
           <https://github.com/Perl/perl5/issues/16017>

       •   Attempting to apply an attribute to an "our" variable where a function of that name
           already exists could result in a NULL pointer being supplied where an SV was expected,
           crashing perl.  [perl #131597] <https://rt.perl.org/Public/Bug/Display.html?id=131597>

       •   The code that vivifies a typeglob out of a code ref made some false assumptions that
           could lead to a crash in cases such as $::{"A"} = sub {}; \&{"A"}.  This has now been
           fixed.  [GH #15937] <https://github.com/Perl/perl5/issues/15937>

       •   "my_atof2" no longer reads beyond the terminating NUL, which previously occurred if
           the decimal point is immediately before the NUL.  [GH #16002]
           <https://github.com/Perl/perl5/issues/16002>

       •   Occasional "Malformed UTF-8 character" crashes in "s//" on utf8 strings have been
           fixed.  [GH #16019] <https://github.com/Perl/perl5/issues/16019>

       •   "perldoc -f s" now finds "s///".  [GH #15989]
           <https://github.com/Perl/perl5/issues/15989>

       •   Some erroneous warnings after utf8 conversion have been fixed.  [GH #15958]
           <https://github.com/Perl/perl5/issues/15958>

       •   The "jmpenv" frame to catch Perl exceptions is set up lazily, and this used to be a
           bit too lazy.  The catcher is now set up earlier, preventing some possible crashes.
           [GH #11804] <https://github.com/Perl/perl5/issues/11804>

       •   Spurious "Assuming NOT a POSIX class" warnings have been removed.  [GH #16001]
           <https://github.com/Perl/perl5/issues/16001>

Acknowledgements

Perl 5.26.1 represents approximately 4 months of development since Perl 5.26.0 and
contains approximately 8,900 lines of changes across 85 files from 23 authors.

Excluding auto-generated files, documentation and release tools, there were approximately
990 lines of changes to 38 .pm, .t, .c and .h files.

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 5.26.1:

Aaron Crane, Andy Dougherty, Aristotle Pagaltzis, Chris 'BinGOs' Williams, Craig A. Berry,
Dagfinn Ilmari Mannsåker, David Mitchell, E. Choroba, Eric Herman, Father Chrysostomos,
Jacques Germishuys, James E Keenan, John SJ Anderson, Karl Williamson, Ken Brown, Lukas
Mai, Matthew Horsfall, Ricardo Signes, Sawyer X, Steve Hay, Tony Cook, Yves Orton, Zefram.

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 perl bug database at
       <https://rt.perl.org/> .  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 see "SECURITY VULNERABILITY CONTACT INFORMATION"
       in perlsec for details of how to report the issue.

Give Thanks

       If you wish to thank the Perl 5 Porters for the work we had done in Perl 5, you can do so
       by running the "perlthanks" program:

           perlthanks

       This will send an email to the Perl 5 Porters list with your show of thanks.