1=encoding utf8 2 3=head1 NAME 4 5perl5223delta - what is new for perl v5.22.3 6 7=head1 DESCRIPTION 8 9This document describes differences between the 5.22.2 release and the 5.22.3 10release. 11 12If you are upgrading from an earlier release such as 5.22.1, first read 13L<perl5222delta>, which describes differences between 5.22.1 and 5.22.2. 14 15=head1 Security 16 17=head2 B<-Di> switch is now required for PerlIO debugging output 18 19Previously PerlIO debugging output would be sent to the file specified by the 20C<PERLIO_DEBUG> environment variable if perl wasn't running setuid and the 21B<-T> or B<-t> switches hadn't been parsed yet. 22 23If perl performed output at a point where it hadn't yet parsed its switches 24this could result in perl creating or overwriting the file named by 25C<PERLIO_DEBUG> even when the B<-T> switch had been supplied. 26 27Perl now requires the B<-Di> switch to produce PerlIO debugging output. By 28default this is written to C<stderr>, but can optionally be redirected to a 29file by setting the C<PERLIO_DEBUG> environment variable. 30 31If perl is running setuid or the B<-T> switch was supplied C<PERLIO_DEBUG> is 32ignored and the debugging output is sent to C<stderr> as for any other B<-D> 33switch. 34 35=head2 Core modules and tools no longer search F<"."> for optional modules 36 37The tools and many modules supplied in core no longer search the default 38current directory entry in L<C<@INC>|perlvar/@INC> for optional modules. For 39example, L<Storable> will remove the final F<"."> from C<@INC> before trying to 40load L<Log::Agent>. 41 42This prevents an attacker injecting an optional module into a process run by 43another user where the current directory is writable by the attacker, e.g. the 44F</tmp> directory. 45 46In most cases this removal should not cause problems, but difficulties were 47encountered with L<base>, which treats every module name supplied as optional. 48These difficulties have not yet been resolved, so for this release there are no 49changes to L<base>. We hope to have a fix for L<base> in Perl 5.22.4. 50 51To protect your own code from this attack, either remove the default F<"."> 52entry from C<@INC> at the start of your script, so: 53 54 #!/usr/bin/perl 55 use strict; 56 ... 57 58becomes: 59 60 #!/usr/bin/perl 61 BEGIN { pop @INC if $INC[-1] eq '.' } 62 use strict; 63 ... 64 65or for modules, remove F<"."> from a localized C<@INC>, so: 66 67 my $can_foo = eval { require Foo; } 68 69becomes: 70 71 my $can_foo = eval { 72 local @INC = @INC; 73 pop @INC if $INC[-1] eq '.'; 74 require Foo; 75 }; 76 77=head1 Incompatible Changes 78 79Other than the security changes above there are no changes intentionally 80incompatible with Perl 5.22.2. If any exist, they are bugs, and we request 81that you submit a report. See L</Reporting Bugs> below. 82 83=head1 Modules and Pragmata 84 85=head2 Updated Modules and Pragmata 86 87=over 4 88 89=item * 90 91L<Archive::Tar> has been upgraded from version 2.04 to 2.04_01. 92 93=item * 94 95L<bignum> has been upgraded from version 0.39 to 0.39_01. 96 97=item * 98 99L<CPAN> has been upgraded from version 2.11 to 2.11_01. 100 101=item * 102 103L<Digest> has been upgraded from version 1.17 to 1.17_01. 104 105=item * 106 107L<Digest::SHA> has been upgraded from version 5.95 to 5.95_01. 108 109=item * 110 111L<Encode> has been upgraded from version 2.72 to 2.72_01. 112 113=item * 114 115L<ExtUtils::Command> has been upgraded from version 1.20 to 1.20_01. 116 117=item * 118 119L<ExtUtils::MakeMaker> has been upgraded from version 7.04_01 to 7.04_02. 120 121=item * 122 123L<File::Fetch> has been upgraded from version 0.48 to 0.48_01. 124 125=item * 126 127L<File::Spec> has been upgraded from version 3.56_01 to 3.56_02. 128 129=item * 130 131L<HTTP::Tiny> has been upgraded from version 0.054 to 0.054_01. 132 133=item * 134 135L<IO> has been upgraded from version 1.35 to 1.35_01. 136 137=item * 138 139The IO-Compress modules have been upgraded from version 2.068 to 2.068_001. 140 141=item * 142 143L<IPC::Cmd> has been upgraded from version 0.92 to 0.92_01. 144 145=item * 146 147L<JSON::PP> has been upgraded from version 2.27300 to 2.27300_01. 148 149=item * 150 151L<Locale::Maketext> has been upgraded from version 1.26 to 1.26_01. 152 153=item * 154 155L<Locale::Maketext::Simple> has been upgraded from version 0.21 to 0.21_01. 156 157=item * 158 159L<Memoize> has been upgraded from version 1.03 to 1.03_01. 160 161=item * 162 163L<Module::CoreList> has been upgraded from version 5.20160429 to 5.20170114_22. 164 165=item * 166 167L<Net::Ping> has been upgraded from version 2.43 to 2.43_01. 168 169=item * 170 171L<Parse::CPAN::Meta> has been upgraded from version 1.4414 to 1.4414_001. 172 173=item * 174 175L<Pod::Html> has been upgraded from version 1.22 to 1.2201. 176 177=item * 178 179L<Pod::Perldoc> has been upgraded from version 3.25 to 3.25_01. 180 181=item * 182 183L<Storable> has been upgraded from version 2.53_01 to 2.53_02. 184 185=item * 186 187L<Sys::Syslog> has been upgraded from version 0.33 to 0.33_01. 188 189=item * 190 191L<Test> has been upgraded from version 1.26 to 1.26_01. 192 193=item * 194 195L<Test::Harness> has been upgraded from version 3.35 to 3.35_01. 196 197=item * 198 199L<XSLoader> has been upgraded from version 0.20 to 0.20_01, fixing a security 200hole in which binary files could be loaded from a path outside of C<@INC>. 201L<[GH #15418]|https://github.com/Perl/perl5/issues/15418> 202 203=back 204 205=head1 Documentation 206 207=head2 Changes to Existing Documentation 208 209=head3 L<perlapio> 210 211=over 4 212 213=item * 214 215The documentation of C<PERLIO_DEBUG> has been updated. 216 217=back 218 219=head3 L<perlrun> 220 221=over 4 222 223=item * 224 225The new B<-Di> switch has been documented, and the documentation of 226C<PERLIO_DEBUG> has been updated. 227 228=back 229 230=head1 Testing 231 232=over 4 233 234=item * 235 236A new test script, F<t/run/switchDx.t>, has been added to test that the new 237B<-Di> switch is working correctly. 238 239=back 240 241=head1 Selected Bug Fixes 242 243=over 4 244 245=item * 246 247The C<PadlistNAMES> macro is an lvalue again. 248 249=back 250 251=head1 Acknowledgements 252 253Perl 5.22.3 represents approximately 9 months of development since Perl 5.22.2 254and contains approximately 4,400 lines of changes across 240 files from 20 255authors. 256 257Excluding auto-generated files, documentation and release tools, there were 258approximately 2,200 lines of changes to 170 .pm, .t, .c and .h files. 259 260Perl continues to flourish into its third decade thanks to a vibrant community 261of users and developers. The following people are known to have contributed 262the improvements that became Perl 5.22.3: 263 264Aaron Crane, Abigail, Alex Vandiver, Aristotle Pagaltzis, Chad Granum, Chris 265'BinGOs' Williams, Craig A. Berry, David Mitchell, Father Chrysostomos, James E 266Keenan, Jarkko Hietaniemi, Karen Etheridge, Karl Williamson, Matthew Horsfall, 267Niko Tyni, Ricardo Signes, Sawyer X, Stevan Little, Steve Hay, Tony Cook. 268 269The list above is almost certainly incomplete as it is automatically generated 270from version control history. In particular, it does not include the names of 271the (very much appreciated) contributors who reported issues to the Perl bug 272tracker. 273 274Many of the changes included in this version originated in the CPAN modules 275included in Perl's core. We're grateful to the entire CPAN community for 276helping Perl to flourish. 277 278For a more complete list of all of Perl's historical contributors, please see 279the F<AUTHORS> file in the Perl source distribution. 280 281=head1 Reporting Bugs 282 283If you find what you think is a bug, you might check the articles recently 284posted to the comp.lang.perl.misc newsgroup and the Perl bug database at 285https://rt.perl.org/ . There may also be information at http://www.perl.org/ , 286the Perl Home Page. 287 288If you believe you have an unreported bug, please run the L<perlbug> program 289included with your release. Be sure to trim your bug down to a tiny but 290sufficient test case. Your bug report, along with the output of C<perl -V>, 291will be sent off to perlbug@perl.org to be analysed by the Perl porting team. 292 293If the bug you are reporting has security implications, which make it 294inappropriate to send to a publicly archived mailing list, then please send it 295to perl5-security-report@perl.org. This points to a closed subscription 296unarchived mailing list, which includes all the core committers, who will be 297able to help assess the impact of issues, figure out a resolution, and help 298co-ordinate the release of patches to mitigate or fix the problem across all 299platforms on which Perl is supported. Please only use this address for 300security issues in the Perl core, not for modules independently distributed on 301CPAN. 302 303=head1 SEE ALSO 304 305The F<Changes> file for an explanation of how to view exhaustive details on 306what changed. 307 308The F<INSTALL> file for how to build Perl. 309 310The F<README> file for general stuff. 311 312The F<Artistic> and F<Copying> files for copyright information. 313 314=cut 315