Fix a Perl security issue.

PR:		208879
Reported by:	Sevan Janiyan
Security:	CVE-2016-2381
Sponsored by:	Absolight
This commit is contained in:
Mathieu Arnold 2016-04-18 11:20:10 +00:00
parent cae7b21042
commit b4de39a093
Notes: svn2git 2021-03-31 03:12:20 +00:00
svn path=/head/; revision=413567
6 changed files with 301 additions and 3 deletions

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@ -3,7 +3,7 @@
PORTNAME= perl
PORTVERSION= ${PERL_VERSION}
PORTREVISION= 20
PORTREVISION= 21
CATEGORIES= lang devel perl5
MASTER_SITES= CPAN/../../src/5.0
DIST_SUBDIR= perl

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@ -0,0 +1,98 @@
commit 7098efff946437a2db6013d12c4fc3193fc328ce
Author: Tony Cook <tony@develop-help.com>
Date: 2016-01-27 11:52:15 +1100
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.
--- perl.c.orig 2014-10-01 01:33:00 UTC
+++ perl.c
@@ -4272,23 +4272,70 @@ S_init_postdump_symbols(pTHX_ int argc,
}
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 */

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@ -3,7 +3,7 @@
PORTNAME= perl
PORTVERSION= ${PERL_VERSION}
PORTREVISION= 11
PORTREVISION= 12
CATEGORIES= lang devel perl5
MASTER_SITES= CPAN/../../src/5.0
DIST_SUBDIR= perl

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@ -0,0 +1,100 @@
commit 7098efff946437a2db6013d12c4fc3193fc328ce
Author: Tony Cook <tony@develop-help.com>
Date: 2016-01-27 11:52:15 +1100
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.
diff --git perl.c perl.c
index d3e378f..25e2075 100644
--- perl.c
+++ perl.c
@@ -4281,23 +4281,70 @@ 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 */

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@ -3,7 +3,7 @@
PORTNAME= perl
DISTVERSION= ${PERL_VERSION}
PORTREVISION= 7
PORTREVISION= 8
CATEGORIES= lang devel perl5
MASTER_SITES= CPAN/../../src/5.0 CPAN/../by-authors/id/S/SH/SHAY
DIST_SUBDIR= perl

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@ -0,0 +1,100 @@
commit 58eaa1131a38c16ee4a66d0bc36288cfde1a39bf
Author: Tony Cook <tony@develop-help.com>
Date: 2016-01-27 11:52:15 +1100
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.
diff --git perl.c perl.c
index 16a6ca4..8ef7474 100644
--- perl.c
+++ perl.c
@@ -4298,23 +4298,70 @@ 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 */