perl: fix CVE-2016-2381

Backport patch to fix CVE-2016-2381 from perl upstream:

http://perl5.git.perl.org/perl.git/commitdiff/ae37b791a73a9e78dedb89fb2429d2628cf58076

(From OE-Core rev: 07ca8a0131f43e9cc2f720e1cdbcb7ba7c074886)

Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 114 insertions, 0 deletions

diff --git a/meta/recipes-devtools/perl/perl/perl-fix-CVE-2016-2381.patch b/meta/recipes-devtools/perl/perl/perl-fix-CVE-2016-2381.patch
new file mode 100644
index 0000000000..0033ae0f63
--- /dev/null
+++ b/meta/recipes-devtools/perl/perl/perl-fix-CVE-2016-2381.patch
@@ -0,0 +1,113 @@
+Upstream-Status: Backport
+
+Backport patch to fix CVE-2016-2381 from
+
+http://perl5.git.perl.org/perl.git/commitdiff/ae37b791a73a9e78dedb89fb2429d2628cf58076
+
+Signed-off-by: Kai Kang <kai.kang@windriver.com>
+---
+From: Tony Cook <tony@develop-help.com>
+Date: Wed, 27 Jan 2016 00:52:15 +0000 (+1100)
+Subject: remove duplicate environment variables from environ
+X-Git-Tag: v5.23.9~170
+X-Git-Url: http://perl5.git.perl.org/perl.git/commitdiff_plain/ae37b791a73a9e78dedb89fb2429d2628cf58076
+
+remove duplicate environment variables from environ
+
+If we see duplicate environment variables while iterating over
+environ[]:
+
+a) make sure we use the same value in %ENV that getenv() returns.
+
+Previously on a duplicate, %ENV would have the last entry for the name
+from environ[], but a typical getenv() would return the first entry.
+
+Rather than assuming all getenv() implementations return the first entry
+explicitly call getenv() to ensure they agree.
+
+b) remove duplicate entries from environ
+
+Previously if there was a duplicate definition for a name in environ[]
+setting that name in %ENV could result in an unsafe value being passed
+to a child process, so ensure environ[] has no duplicates.
+
+CVE-2016-2381
+---
+
+diff --git a/perl.c b/perl.c
+index 4a324c6..5c71fd0 100644
+--- a/perl.c
++++ b/perl.c
+@@ -4329,23 +4329,70 @@ S_init_postdump_symbols(pTHX_ int argc, char **argv, char **env)
+        }
+        if (env) {
+          char *s, *old_var;
++          STRLEN nlen;
+          SV *sv;
++          HV *dups = newHV();
++
+          for (; *env; env++) {
+            old_var = *env;
+ 
+            if (!(s = strchr(old_var,'=')) || s == old_var)
+                continue;
++            nlen = s - old_var;
+ 
+ #if defined(MSDOS) && !defined(DJGPP)
+            *s = '\0';
+            (void)strupr(old_var);
+            *s = '=';
+ #endif
+-           sv = newSVpv(s+1, 0);
+-           (void)hv_store(hv, old_var, s - old_var, sv, 0);
++            if (hv_exists(hv, old_var, nlen)) {
++                const char *name = savepvn(old_var, nlen);
++
++                /* make sure we use the same value as getenv(), otherwise code that
++                   uses getenv() (like setlocale()) might see a different value to %ENV
++                 */
++                sv = newSVpv(PerlEnv_getenv(name), 0);
++
++                /* keep a count of the dups of this name so we can de-dup environ later */
++                if (hv_exists(dups, name, nlen))
++                    ++SvIVX(*hv_fetch(dups, name, nlen, 0));
++                else
++                    (void)hv_store(dups, name, nlen, newSViv(1), 0);
++
++                Safefree(name);
++            }
++            else {
++                sv = newSVpv(s+1, 0);
++            }
++           (void)hv_store(hv, old_var, nlen, sv, 0);
+            if (env_is_not_environ)
+                mg_set(sv);
+          }
++          if (HvKEYS(dups)) {
++              /* environ has some duplicate definitions, remove them */
++              HE *entry;
++              hv_iterinit(dups);
++              while ((entry = hv_iternext_flags(dups, 0))) {
++                  STRLEN nlen;
++                  const char *name = HePV(entry, nlen);
++                  IV count = SvIV(HeVAL(entry));
++                  IV i;
++                  SV **valp = hv_fetch(hv, name, nlen, 0);
++
++                  assert(valp);
++
++                  /* try to remove any duplicate names, depending on the
++                   * implementation used in my_setenv() the iteration might
++                   * not be necessary, but let's be safe.
++                   */
++                  for (i = 0; i < count; ++i)
++                      my_setenv(name, 0);
++
++                  /* and set it back to the value we set $ENV{name} to */
++                  my_setenv(name, SvPV_nolen(*valp));
++              }
++          }
++          SvREFCNT_dec_NN(dups);
+       }
+ #endif /* USE_ENVIRON_ARRAY */
+ #endif /* !PERL_MICRO */
diff --git a/meta/recipes-devtools/perl/perl_5.22.1.bb b/meta/recipes-devtools/perl/perl_5.22.1.bb
index 3bd0a6debc..04a2b6f481 100644
--- a/meta/recipes-devtools/perl/perl_5.22.1.bb
+++ b/meta/recipes-devtools/perl/perl_5.22.1.bb
@@ -65,6 +65,7 @@ SRC_URI += " \
         file://perl-errno-generation-gcc5.patch \
         file://perl-fix-conflict-between-skip_all-and-END.patch \
         file://perl-test-customized.patch \
+        file://perl-fix-CVE-2016-2381.patch \
 "
 
 # Fix test case issues