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

Provided by: perl-doc_5.38.2-3.2ubuntu0.1_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.