Make Cwd::fastcwd() return a tainted value.

Add regression tests for taint-safety of the *cwd()
functions.

p4raw-id: //depot/perl@16635

diff --git a/ext/Cwd/Cwd.xs b/ext/Cwd/Cwd.xs
index f53f6ee..3f7b93b 100644 (file)
--- a/ext/Cwd/Cwd.xs
+++ b/ext/Cwd/Cwd.xs
@@ -222,6 +222,9 @@ PPCODE:
     dXSTARG;
     getcwd_sv(TARG);
     XSprePUSH; PUSHTARG;
+#ifndef INCOMPLETE_TAINTS
+    SvTAINTED_on(TARG);
+#endif
 }
 
 void

diff --git a/ext/Cwd/t/taint.t b/ext/Cwd/t/taint.t
index 74e2d65..3f6aa52 100644 (file)
--- a/ext/Cwd/t/taint.t
+++ b/ext/Cwd/t/taint.t
@@ -7,15 +7,18 @@ BEGIN {
 }
 
 use Cwd;
-use Test::More tests => 2;
-
-# The normal kill() trick is not portable.
-sub is_tainted { 
-    return ! eval { eval("#" . substr(join("", @_), 0, 0)); 1 };
-}
+use Test::More tests => 6;
+use Scalar::Util qw/tainted/;
 
 my $cwd;
 eval { $cwd = getcwd; };
-is( $@, '',                 'getcwd() does not explode under taint mode' );
-ok( is_tainted($cwd),       "its return value is tainted" );
+is( $@, '',            'getcwd() does not explode under taint mode' );
+ok( tainted($cwd),     "its return value is tainted" );
+
+eval { $cwd = cwd; };
+is( $@, '',            'cwd() does not explode under taint mode' );
+ok( tainted($cwd),     "its return value is tainted" );
 
+eval { $cwd = fastcwd; };
+is( $@, '',            'fastcwd() does not explode under taint mode' );
+ok( tainted($cwd),     "its return value is tainted" );

diff --git a/lib/Cwd.pm b/lib/Cwd.pm
index d1ad76e..8b00543 100644 (file)
--- a/lib/Cwd.pm
+++ b/lib/Cwd.pm
@@ -48,7 +48,7 @@ The cwd() is the most natural form for the current architecture. For
 most systems it is identical to `pwd` (but without the trailing line
 terminator).
 
-Unfortunately, cwd() is B<not> taint-safe.
+Taint-safe.
 
 =item fastcwd
 
@@ -105,7 +105,8 @@ Taint-safe.
 
 A more dangerous, but potentially faster version of abs_path.
 
-B<Not> taint-safe.
+This function is B<Not> taint-safe : you can't use it in programs
+that work under taint mode.
 
 =back
 
@@ -270,9 +271,9 @@ sub fastcwd {
     $path = '/' . join('/', @path);
     if ($^O eq 'apollo') { $path = "/".$path; }
     # At this point $path may be tainted (if tainting) and chdir would fail.
-    # To be more useful we untaint it then check that we landed where we started.
-    $path = $1 if $path =~ /^(.*)\z/s; # untaint
-    CORE::chdir($path) || return undef;
+    # Untaint it then check that we landed where we started.
+    $path =~ /^(.*)\z/s                # untaint
+       && CORE::chdir($1) or return undef;
     ($cdev, $cino) = stat('.');
     die "Unstable directory path, current directory changed unexpectedly"
        if $cdev != $orig_cdev || $cino != $orig_cino;