Abandon the use of Perl's Safe.pm to enforce restrictions in plperl, as it is

fundamentally insecure. Instead apply an opmask to the whole interpreter that
imposes restrictions on unsafe operations. These restrictions are much harder
to subvert than is Safe.pm, since there is no container to be broken out of.
Backported to release 7.4.

In releases 7.4, 8.0 and 8.1 this also includes the necessary backporting of
the two interpreters model for plperl and plperlu adopted in release 8.2.

In versions 8.0 and up, the use of Perl's POSIX module to undo its locale
mangling on Windows has become insecure with these changes, so it is
replaced by our own routine, which is also faster.

Nice side effects of the changes include that it is now possible to use perl's
"strict" pragma in a natural way in plperl, and that perl's $a and
$b variables now work as expected in sort routines, and that function
compilation is significantly faster.

Tim Bunce and Andrew Dunstan, with reviews from Alex Hunsaker and
Alexey Klyukin.

Security: CVE-2010-1169

doc/src/sgml/plperl.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/plperl.sgml,v 2.67 2008/01/25 15:28:35 adunstan Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/plperl.sgml,v 2.67.2.1 2010/05/13 16:42:51 adunstan Exp $ -->
 
  <chapter id="plperl">
   <title>PL/Perl - Perl Procedural Language</title>
@@ -293,12 +293,7 @@ SELECT * FROM perl_set();
 <programlisting>
 use strict;
 </programlisting>
-   in the function body.  But this only works in <application>PL/PerlU</>
-   functions, since <literal>use</> is not a trusted operation.  In
-   <application>PL/Perl</> functions you can instead do:
-<programlisting>
-BEGIN { strict->import(); }
-</programlisting>
+   in the function body.
   </para>
  </sect1>
 

src/pl/plperl/GNUmakefile

 # Makefile for PL/Perl
-# $PostgreSQL: pgsql/src/pl/plperl/GNUmakefile,v 1.33.2.1 2009/06/05 18:31:48 adunstan Exp $
+# $PostgreSQL: pgsql/src/pl/plperl/GNUmakefile,v 1.33.2.2 2010/05/13 16:42:51 adunstan Exp $
 
 subdir = src/pl/plperl
 top_builddir = ../../..
@@ -27,7 +27,7 @@ override CPPFLAGS += -DPLPERL_HAVE_UID_GID
 override CFLAGS += -Wno-comment
 endif
 
-override CPPFLAGS := -I$(srcdir) $(CPPFLAGS) -I$(perl_archlibexp)/CORE
+override CPPFLAGS := -I. -I$(srcdir) $(CPPFLAGS) -I$(perl_archlibexp)/CORE
 
 rpathdir = $(perl_archlibexp)/CORE
 
@@ -40,8 +40,15 @@ OBJS = plperl.o spi_internal.o SPI.o
 
 SHLIB_LINK = $(perl_embed_ldflags) $(BE_DLLLIBS)
 
-REGRESS_OPTS = --dbname=$(PL_TESTDB) --load-language=plperl
+REGRESS_OPTS = --dbname=$(PL_TESTDB) --load-language=plperl  --load-language=plperlu
 REGRESS = plperl plperl_trigger plperl_shared plperl_elog
+# if Perl can support two interpreters in one backend, 
+# test plperl-and-plperlu cases
+ifneq ($(PERL),)
+ifeq ($(shell $(PERL) -V:usemultiplicity), usemultiplicity='define';)
+	REGRESS += plperlu_plperl
+endif
+endif
 # where to find psql for running the tests
 PSQLDIR = $(bindir)
 
@@ -50,6 +57,12 @@ include $(top_srcdir)/src/Makefile.shlib
 
 all: all-lib
 
+plperl.o: plperl_opmask.h
+
+plperl_opmask.h: plperl_opmask.pl
+	$(PERL) $< $@
+
+
 SPI.c: SPI.xs
 	$(PERL) $(perl_privlibexp)/ExtUtils/xsubpp -typemap $(perl_privlibexp)/ExtUtils/typemap $< >$@
 
@@ -97,7 +110,7 @@ submake:
 	$(MAKE) -C $(top_builddir)/src/test/regress pg_regress$(X)
 
 clean distclean maintainer-clean: clean-lib
-	rm -f SPI.c $(OBJS)
+	rm -f SPI.c $(OBJS) plperl_opmask.h
 	rm -rf results
 	rm -f regression.diffs regression.out
 

src/pl/plperl/expected/plperl.out

@@ -497,3 +497,9 @@ CREATE OR REPLACE FUNCTION perl_spi_prepared_bad(double precision) RETURNS doubl
 $$ LANGUAGE plperl;
 SELECT perl_spi_prepared_bad(4.35) as "double precision";
 ERROR:  error from Perl function "perl_spi_prepared_bad": type "does_not_exist" does not exist at line 2.
+--
+-- Test detection of unsafe operations
+CREATE OR REPLACE FUNCTION perl_unsafe1() RETURNS void AS $$
+	my $fd = fileno STDERR;
+$$ LANGUAGE plperl;
+ERROR:  creation of Perl function "perl_unsafe1" failed: 'fileno' trapped by operation mask at line 2.

src/pl/plperl/expected/plperlu_plperl.out

+--
+-- Test that recursing between plperl and plperlu doesn't allow plperl to perform unsafe ops
+--
+-- recurse between a plperl and plperlu function that are identical except that
+-- each calls the other. Each also checks if an unsafe opcode can be executed.
+CREATE OR REPLACE FUNCTION recurse_plperl(i int) RETURNS SETOF TEXT LANGUAGE plperl
+AS $$
+	my $i = shift;
+	return unless $i > 0;
+	return_next "plperl  $i entry: ".((eval "stat;1") ? "ok" : $@);
+	return_next $_
+		for map { $_->{recurse_plperlu} }
+			@{spi_exec_query("select * from recurse_plperlu($i-1)")->{rows}};
+	return;
+$$;
+CREATE OR REPLACE FUNCTION recurse_plperlu(i int) RETURNS SETOF TEXT LANGUAGE plperlu
+AS $$
+	my $i = shift;
+	return unless $i > 0;
+	return_next "plperlu $i entry: ".((eval "stat;1") ? "ok" : $@);
+	return_next $_
+		for map { $_->{recurse_plperl} }
+			@{spi_exec_query("select * from recurse_plperl($i-1)")->{rows}};
+	return;
+$$;
+SELECT * FROM recurse_plperl(5);
+                        recurse_plperl                        
+--------------------------------------------------------------
+ plperl  5 entry: 'stat' trapped by operation mask at line 1.
+ 
+ plperlu 4 entry: ok
+ plperl  3 entry: 'stat' trapped by operation mask at line 1.
+ 
+ plperlu 2 entry: ok
+ plperl  1 entry: 'stat' trapped by operation mask at line 1.
+ 
+(5 rows)
+
+SELECT * FROM recurse_plperlu(5);
+                       recurse_plperlu                        
+--------------------------------------------------------------
+ plperlu 5 entry: ok
+ plperl  4 entry: 'stat' trapped by operation mask at line 1.
+ 
+ plperlu 3 entry: ok
+ plperl  2 entry: 'stat' trapped by operation mask at line 1.
+ 
+ plperlu 1 entry: ok
+(5 rows)
+
+--
+-- Make sure we can't use/require things in plperl
+--
+CREATE OR REPLACE FUNCTION use_plperlu() RETURNS void LANGUAGE plperlu
+AS $$
+use Errno;
+$$;
+CREATE OR REPLACE FUNCTION use_plperl() RETURNS void LANGUAGE plperl
+AS $$
+use Errno;
+$$;
+ERROR:  creation of Perl function "use_plperl" failed: Unable to load Errno.pm into plperl at line 2.
+BEGIN failed--compilation aborted at line 2.
+-- make sure our overloaded require op gets restored/set correctly
+select use_plperlu();
+ use_plperlu 
+-------------
+ 
+(1 row)
+
+CREATE OR REPLACE FUNCTION use_plperl() RETURNS void LANGUAGE plperl
+AS $$
+use Errno;
+$$;
+ERROR:  creation of Perl function "use_plperl" failed: Unable to load Errno.pm into plperl at line 2.
+BEGIN failed--compilation aborted at line 2.

src/pl/plperl/plperl.c

 /**********************************************************************
  * plperl.c - perl as a procedural language for PostgreSQL
  *
- *	  $PostgreSQL: pgsql/src/pl/plperl/plperl.c,v 1.136.2.8 2010/03/09 22:34:58 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/pl/plperl/plperl.c,v 1.136.2.9 2010/05/13 16:42:51 adunstan Exp $
  *
  **********************************************************************/
 
@@ -32,6 +32,8 @@
 
 /* perl stuff */
 #include "plperl.h"
+/* defines PLPERL_SET_OPMASK */
+#include "plperl_opmask.h"
 
 PG_MODULE_MAGIC;
 
@@ -121,9 +123,13 @@ static bool plperl_safe_init_done = false;
 static PerlInterpreter *plperl_trusted_interp = NULL;
 static PerlInterpreter *plperl_untrusted_interp = NULL;
 static PerlInterpreter *plperl_held_interp = NULL;
+static OP  *(*pp_require_orig) (pTHX) = NULL;
+static OP  *pp_require_safe(pTHX);
 static bool trusted_context;
 static HTAB *plperl_proc_hash = NULL;
 static HTAB *plperl_query_hash = NULL;
+static char plperl_opmask[MAXO];
+static void set_interp_require(void);
 
 static bool plperl_use_strict = false;
 
@@ -152,6 +158,11 @@ static SV **hv_store_string(HV *hv, const char *key, SV *val);
 static SV **hv_fetch_string(HV *hv, const char *key);
 static SV  *plperl_create_sub(char *proname, char *s, bool trusted);
 static SV  *plperl_call_perl_func(plperl_proc_desc *desc, FunctionCallInfo fcinfo);
+static char *strip_trailing_ws(const char *msg);
+
+#ifdef WIN32
+static char *setlocale_perl(int category, char *locale);
+#endif
 
 /*
  * This routine is a crock, and so is everyplace that calls it.  The problem
@@ -211,6 +222,8 @@ _PG_init(void)
 									&hash_ctl,
 									HASH_ELEM);
 
+	PLPERL_SET_OPMASK(plperl_opmask);
+
 	plperl_init_interp();
 
 	inited = true;
@@ -226,11 +239,11 @@ _PG_init(void)
 	"sub ::plperl_die { my $msg = shift; " \
 	"       $msg =~ s/\\(eval \\d+\\) //g; die $msg; } " \
 	"$SIG{__DIE__} = \\&::plperl_die; " \
-	"sub ::mkunsafefunc {" \
+	"sub ::mkfunc {" \
 	"      my $ret = eval(qq[ sub { $_[0] $_[1] } ]); " \
 	"      $@ =~ s/\\(eval \\d+\\) //g if $@; return $ret; }" \
 	"use strict; " \
-	"sub ::mk_strict_unsafefunc {" \
+	"sub ::mk_strict_func {" \
 	"      my $ret = eval(qq[ sub { use strict; $_[0] $_[1] } ]); " \
 	"      $@ =~ s/\\(eval \\d+\\) //g if $@; return $ret; } " \
 	"sub ::_plperl_to_pg_array {" \
@@ -257,44 +270,8 @@ _PG_init(void)
 	"  return qq({$res}); " \
 	"} "
 
-#define SAFE_MODULE \
-	"require Safe; $Safe::VERSION"
-
-/* 
- * The temporary enabling of the caller opcode here is to work around a
- * bug in perl 5.10, which unkindly changed the way its Safe.pm works, without
- * notice. It is quite safe, as caller is informational only, and in any case
- * we only enable it while we load the 'strict' module.
- */
-
-#define SAFE_OK \
-	"use vars qw($PLContainer); $PLContainer = new Safe('PLPerl');" \
-	"$PLContainer->permit_only(':default');" \
-	"$PLContainer->permit(qw[:base_math !:base_io sort time]);" \
-	"$PLContainer->share(qw[&elog &spi_exec_query &return_next " \
-	"&spi_query &spi_fetchrow &spi_cursor_close " \
-	"&spi_prepare &spi_exec_prepared &spi_query_prepared &spi_freeplan " \
-	"&_plperl_to_pg_array " \
-	"&DEBUG &LOG &INFO &NOTICE &WARNING &ERROR %_SHARED ]);" \
-	"sub ::mksafefunc {" \
-	"      my $ret = $PLContainer->reval(qq[sub { $_[0] $_[1] }]); " \
-	"      $@ =~ s/\\(eval \\d+\\) //g if $@; return $ret; }" \
-	"$PLContainer->permit(qw[require caller]); $PLContainer->reval('use strict;');" \
-	"$PLContainer->deny(qw[require caller]); " \
-	"sub ::mk_strict_safefunc {" \
-	"      my $ret = $PLContainer->reval(qq[sub { BEGIN { strict->import(); } $_[0] $_[1] }]); " \
-	"      $@ =~ s/\\(eval \\d+\\) //g if $@; return $ret; }"
-
-#define SAFE_BAD \
-	"use vars qw($PLContainer); $PLContainer = new Safe('PLPerl');" \
-	"$PLContainer->permit_only(':default');" \
-	"$PLContainer->share(qw[&elog &ERROR ]);" \
-	"sub ::mksafefunc { return $PLContainer->reval(qq[sub { " \
-	"      elog(ERROR,'trusted Perl functions disabled - " \
-	"      please upgrade Perl Safe module to version 2.09 or later');}]); }" \
-	"sub ::mk_strict_safefunc { return $PLContainer->reval(qq[sub { " \
-	"      elog(ERROR,'trusted Perl functions disabled - " \
-	"      please upgrade Perl Safe module to version 2.09 or later');}]); }"
+#define PLC_TRUSTED \
+	"require strict; "
 
 #define TEST_FOR_MULTI \
 	"use Config; " \
@@ -303,6 +280,21 @@ _PG_init(void)
 	" and $Config{useithreads} eq 'define')"
 
 
+static void
+set_interp_require(void)
+{
+	if (trusted_context)
+	{
+		PL_ppaddr[OP_REQUIRE] = pp_require_safe;
+		PL_ppaddr[OP_DOFILE] = pp_require_safe;
+	}
+	else
+	{
+		PL_ppaddr[OP_REQUIRE] = pp_require_orig;
+		PL_ppaddr[OP_DOFILE] = pp_require_orig;
+	}
+}
+
 /********************************************************************
  *
  * We start out by creating a "held" interpreter that we can use in
@@ -332,6 +324,7 @@ check_interp(bool trusted)
 		}
 		plperl_held_interp = NULL;
 		trusted_context = trusted;
+		set_interp_require();
 	}
 	else if (interp_state == INTERP_BOTH ||
 			 (trusted && interp_state == INTERP_TRUSTED) ||
@@ -344,6 +337,7 @@ check_interp(bool trusted)
 			else
 				PERL_SET_CONTEXT(plperl_untrusted_interp);
 			trusted_context = trusted;
+			set_interp_require();
 		}
 	}
 	else if (can_run_two)
@@ -357,6 +351,7 @@ check_interp(bool trusted)
 		interp_state = INTERP_BOTH;
 		plperl_held_interp = NULL;
 		trusted_context = trusted;
+		set_interp_require();
 	}
 	else
 	{
@@ -377,7 +372,9 @@ restore_context(bool old_context)
 			PERL_SET_CONTEXT(plperl_trusted_interp);
 		else
 			PERL_SET_CONTEXT(plperl_untrusted_interp);
+
 		trusted_context = old_context;
+		set_interp_require();
 	}
 }
 
@@ -388,9 +385,9 @@ plperl_init_interp(void)
 		"", "-e", PERLBOOT
 	};
 
-	int nargs = 3;
+	int			nargs = 3;
 
-	char *dummy_perl_env[1] = { NULL }; 
+	char	   *dummy_perl_env[1] = {NULL};
 
 #ifdef WIN32
 
@@ -409,7 +406,7 @@ plperl_init_interp(void)
 	 * subsequent calls to the interpreter don't mess with the locale
 	 * settings.
 	 *
-	 * We restore them using Perl's POSIX::setlocale() function so that Perl
+	 * We restore them using Perl's perl_setlocale() function so that Perl
 	 * doesn't have a different idea of the locale from Postgres.
 	 *
 	 */
@@ -420,7 +417,6 @@ plperl_init_interp(void)
 			   *save_monetary,
 			   *save_numeric,
 			   *save_time;
-	char		buf[1024];
 
 	loc = setlocale(LC_COLLATE, NULL);
 	save_collate = loc ? pstrdup(loc) : NULL;
@@ -432,6 +428,11 @@ plperl_init_interp(void)
 	save_numeric = loc ? pstrdup(loc) : NULL;
 	loc = setlocale(LC_TIME, NULL);
 	save_time = loc ? pstrdup(loc) : NULL;
+
+#define PLPERL_RESTORE_LOCALE(name, saved) \
+	  STMT_START { \
+			  if (saved != NULL) { setlocale_perl(name, saved); pfree(saved); } \
+	  } STMT_END
 #endif
 
 	/****
@@ -446,7 +447,7 @@ plperl_init_interp(void)
 #if defined(PERL_SYS_INIT3) && !defined(MYMALLOC)
 	/* only call this the first time through, as per perlembed man page */
 	if (interp_state == INTERP_NONE)
-		PERL_SYS_INIT3(&nargs, (char ***) &embedding, (char***)&dummy_perl_env);
+		PERL_SYS_INIT3(&nargs, (char ***) &embedding, (char ***) &dummy_perl_env);
 #endif
 
 	plperl_held_interp = perl_alloc();
@@ -454,6 +455,20 @@ plperl_init_interp(void)
 		elog(ERROR, "could not allocate Perl interpreter");
 
 	perl_construct(plperl_held_interp);
+
+	/*
+	 * Record the original function for the 'require' and 'dofile' opcodes.
+	 * (They share the same implementation.) Ensure it's used for new
+	 * interpreters.
+	 */
+	if (!pp_require_orig)
+		pp_require_orig = PL_ppaddr[OP_REQUIRE];
+	else
+	{
+		PL_ppaddr[OP_REQUIRE] = pp_require_orig;
+		PL_ppaddr[OP_DOFILE] = pp_require_orig;
+	}
+
 	perl_parse(plperl_held_interp, plperl_init_shared_libs,
 			   nargs, embedding, NULL);
 	perl_run(plperl_held_interp);
@@ -467,108 +482,110 @@ plperl_init_interp(void)
 		interp_state = INTERP_HELD;
 	}
 
-#ifdef WIN32
+#ifdef PLPERL_RESTORE_LOCALE
+	PLPERL_RESTORE_LOCALE(LC_COLLATE, save_collate);
+	PLPERL_RESTORE_LOCALE(LC_CTYPE, save_ctype);
+	PLPERL_RESTORE_LOCALE(LC_MONETARY, save_monetary);
+	PLPERL_RESTORE_LOCALE(LC_NUMERIC, save_numeric);
+	PLPERL_RESTORE_LOCALE(LC_TIME, save_time);
+#endif
 
-	eval_pv("use POSIX qw(locale_h);", TRUE);	/* croak on failure */
+}
 
-	if (save_collate != NULL)
-	{
-		snprintf(buf, sizeof(buf), "setlocale(%s,'%s');",
-				 "LC_COLLATE", save_collate);
-		eval_pv(buf, TRUE);
-		pfree(save_collate);
-	}
-	if (save_ctype != NULL)
-	{
-		snprintf(buf, sizeof(buf), "setlocale(%s,'%s');",
-				 "LC_CTYPE", save_ctype);
-		eval_pv(buf, TRUE);
-		pfree(save_ctype);
-	}
-	if (save_monetary != NULL)
-	{
-		snprintf(buf, sizeof(buf), "setlocale(%s,'%s');",
-				 "LC_MONETARY", save_monetary);
-		eval_pv(buf, TRUE);
-		pfree(save_monetary);
-	}
-	if (save_numeric != NULL)
-	{
-		snprintf(buf, sizeof(buf), "setlocale(%s,'%s');",
-				 "LC_NUMERIC", save_numeric);
-		eval_pv(buf, TRUE);
-		pfree(save_numeric);
-	}
-	if (save_time != NULL)
-	{
-		snprintf(buf, sizeof(buf), "setlocale(%s,'%s');",
-				 "LC_TIME", save_time);
-		eval_pv(buf, TRUE);
-		pfree(save_time);
-	}
-#endif
+/*
+ * Our safe implementation of the require opcode.
+ * This is safe because it's completely unable to load any code.
+ * If the requested file/module has already been loaded it'll return true.
+ * If not, it'll die.
+ * So now "use Foo;" will work iff Foo has already been loaded.
+ */
+static OP  *
+pp_require_safe(pTHX)
+{
+	dVAR;
+	dSP;
+	SV		   *sv,
+			  **svp;
+	char	   *name;
+	STRLEN		len;
 
+	sv = POPs;
+	name = SvPV(sv, len);
+	if (!(name && len > 0 && *name))
+		RETPUSHNO;
+
+	svp = hv_fetch(GvHVn(PL_incgv), name, len, 0);
+	if (svp && *svp != &PL_sv_undef)
+		RETPUSHYES;
+
+	DIE(aTHX_ "Unable to load %s into plperl", name);
 }
 
 
+
 static void
 plperl_safe_init(void)
 {
-	SV		   *res;
-	double		safe_version;
+	HV		   *stash;
+	SV		   *sv;
+	char	   *key;
+	I32			klen;
 
-	res = eval_pv(SAFE_MODULE, FALSE);	/* TRUE = croak if failure */
+	/* use original require while we set up */
+	PL_ppaddr[OP_REQUIRE] = pp_require_orig;
+	PL_ppaddr[OP_DOFILE] = pp_require_orig;
 
-	safe_version = SvNV(res);
+	eval_pv(PLC_TRUSTED, FALSE);
+	if (SvTRUE(ERRSV))
+		ereport(ERROR,
+				(errmsg("%s", strip_trailing_ws(SvPV_nolen(ERRSV))),
+				 errcontext("While executing PLC_TRUSTED.")));
 
-	/*
-	 * We actually want to reject safe_version < 2.09, but it's risky to
-	 * assume that floating-point comparisons are exact, so use a slightly
-	 * smaller comparison value.
-	 */
-	if (safe_version < 2.0899)
+	if (GetDatabaseEncoding() == PG_UTF8)
 	{
-		/* not safe, so disallow all trusted funcs */
-		eval_pv(SAFE_BAD, FALSE);
+		/*
+		 * Force loading of utf8 module now to prevent errors that can arise
+		 * from the regex code later trying to load utf8 modules. See
+		 * http://rt.perl.org/rt3/Ticket/Display.html?id=47576
+		 */
+		eval_pv("my $a=chr(0x100); return $a =~ /\\xa9/i", FALSE);
+		if (SvTRUE(ERRSV))
+			ereport(ERROR,
+					(errmsg("%s", strip_trailing_ws(SvPV_nolen(ERRSV))),
+					 errcontext("While executing utf8fix.")));
 	}
-	else
+
+	/*
+	 * Lock down the interpreter
+	 */
+
+	/* switch to the safe require/dofile opcode for future code */
+	PL_ppaddr[OP_REQUIRE] = pp_require_safe;
+	PL_ppaddr[OP_DOFILE] = pp_require_safe;
+
+	/* 
+	 * prevent (any more) unsafe opcodes being compiled 
+	 * PL_op_mask is per interpreter, so this only needs to be set once 
+	 */
+	PL_op_mask = plperl_opmask;
+
+	/* delete the DynaLoader:: namespace so extensions can't be loaded */
+	stash = gv_stashpv("DynaLoader", GV_ADDWARN);
+	hv_iterinit(stash);
+	while ((sv = hv_iternextsv(stash, &key, &klen)))
 	{
-		eval_pv(SAFE_OK, FALSE);
-		if (GetDatabaseEncoding() == PG_UTF8)
-		{
-			/* 
-			 * Fill in just enough information to set up this perl
-			 * function in the safe container and call it.
-			 * For some reason not entirely clear, it prevents errors that
-			 * can arise from the regex code later trying to load
-			 * utf8 modules.
-			 */
-			plperl_proc_desc desc;			
-			FunctionCallInfoData fcinfo;
-			SV *ret;
-			SV *func;
-
-			/* make sure we don't call ourselves recursively */
-			plperl_safe_init_done = true;
-
-			/* compile the function */
-			func = plperl_create_sub("utf8fix",
-							 "return shift =~ /\\xa9/i ? 'true' : 'false' ;",
-									 true);
-
-			/* set up to call the function with a single text argument 'a' */
-			desc.reference = func;
-			desc.nargs = 1;
-			desc.arg_is_rowtype[0] = false;
-			fmgr_info(F_TEXTOUT, &(desc.arg_out_func[0]));
-
-			fcinfo.arg[0] = DirectFunctionCall1(textin, CStringGetDatum("a"));
-			fcinfo.argnull[0] = false;
-			
-			/* and make the call */
-			ret = plperl_call_perl_func(&desc, &fcinfo);
-		}
+		if (!isGV_with_GP(sv) || !GvCV(sv))
+			continue;
+		SvREFCNT_dec(GvCV(sv)); /* free the CV */
+		GvCV(sv) = NULL;		/* prevent call via GV */
 	}
+	hv_clear(stash);
+	/* invalidate assorted caches */
+	++PL_sub_generation;
+#ifdef PL_stashcache
+	hv_clear(PL_stashcache);
+#endif
+
 
 	plperl_safe_init_done = true;
 }
@@ -950,7 +967,7 @@ plperl_validator(PG_FUNCTION_ARGS)
 
 
 /*
- * Uses mksafefunc/mkunsafefunc to create an anonymous sub whose text is
+ * Uses mkfunc to create an anonymous sub whose text is
  * supplied in s, and returns a reference to the closure.
  */
 static SV  *
@@ -980,14 +997,10 @@ plperl_create_sub(char *proname, char *s, bool trusted)
 	 * inside mksafefunc?
 	 */
 
-	if (trusted && plperl_use_strict)
-		compile_sub = "::mk_strict_safefunc";
-	else if (plperl_use_strict)
-		compile_sub = "::mk_strict_unsafefunc";
-	else if (trusted)
-		compile_sub = "::mksafefunc";
+	if (plperl_use_strict)
+		compile_sub = "::mk_strict_func";
 	else
-		compile_sub = "::mkunsafefunc";
+		compile_sub = "::mkfunc";
 
 	count = perl_call_pv(compile_sub, G_SCALAR | G_EVAL | G_KEEPERR);
 	SPAGAIN;
@@ -1044,7 +1057,7 @@ plperl_create_sub(char *proname, char *s, bool trusted)
  * plperl_init_shared_libs()		-
  *
  * We cannot use the DynaLoader directly to get at the Opcode
- * module (used by Safe.pm). So, we link Opcode into ourselves
+ * module. So, we link Opcode into ourselves
  * and do the initialization behind perl's back.
  *
  **********************************************************************/
@@ -1513,7 +1526,8 @@ compile_plperl_function(Oid fn_oid, bool is_trigger)
 		{
 			hash_search(plperl_proc_hash, internal_proname,
 						HASH_REMOVE, NULL);
-			if (prodesc->reference) {
+			if (prodesc->reference)
+			{
 				check_interp(prodesc->lanpltrusted);
 				SvREFCNT_dec(prodesc->reference);
 				restore_context(oldcontext);
@@ -2668,3 +2682,79 @@ hv_fetch_string(HV *hv, const char *key)
 #endif
 	return hv_fetch(hv, key, klen, 0);
 }
+
+
+/*
+ * Perl's own setlocal() copied from POSIX.xs
+ * (needed because of the calls to new_*())
+ */
+#ifdef WIN32
+static char *
+setlocale_perl(int category, char *locale)
+{
+	char	   *RETVAL = setlocale(category, locale);
+
+	if (RETVAL)
+	{
+#ifdef USE_LOCALE_CTYPE
+		if (category == LC_CTYPE
+#ifdef LC_ALL
+			|| category == LC_ALL
+#endif
+			)
+		{
+			char	   *newctype;
+
+#ifdef LC_ALL
+			if (category == LC_ALL)
+				newctype = setlocale(LC_CTYPE, NULL);
+			else
+#endif
+				newctype = RETVAL;
+			new_ctype(newctype);
+		}
+#endif   /* USE_LOCALE_CTYPE */
+#ifdef USE_LOCALE_COLLATE
+		if (category == LC_COLLATE
+#ifdef LC_ALL
+			|| category == LC_ALL
+#endif
+			)
+		{
+			char	   *newcoll;
+
+#ifdef LC_ALL
+			if (category == LC_ALL)
+				newcoll = setlocale(LC_COLLATE, NULL);
+			else
+#endif
+				newcoll = RETVAL;
+			new_collate(newcoll);
+		}
+#endif   /* USE_LOCALE_COLLATE */
+
+
+#ifdef USE_LOCALE_NUMERIC
+		if (category == LC_NUMERIC
+#ifdef LC_ALL
+			|| category == LC_ALL
+#endif
+			)
+		{
+			char	   *newnum;
+
+#ifdef LC_ALL
+			if (category == LC_ALL)
+				newnum = setlocale(LC_NUMERIC, NULL);
+			else
+#endif
+				newnum = RETVAL;
+			new_numeric(newnum);
+		}
+#endif   /* USE_LOCALE_NUMERIC */
+	}
+
+	return RETVAL;
+}
+
+#endif

src/pl/plperl/plperl_opmask.pl

+#!perl -w
+
+use strict;
+use warnings;
+
+use Opcode qw(opset opset_to_ops opdesc full_opset);
+
+my $plperl_opmask_h   = shift
+	or die "Usage: $0 <output_filename.h>\n";
+
+my $plperl_opmask_tmp = $plperl_opmask_h."tmp";
+END { unlink $plperl_opmask_tmp }
+
+open my $fh, ">", "$plperl_opmask_tmp"
+	or die "Could not write to $plperl_opmask_tmp: $!";
+
+printf $fh "#define PLPERL_SET_OPMASK(opmask) \\\n";
+printf $fh "  memset(opmask, 1, MAXO);\t/* disable all */ \\\n";
+printf $fh "  /* then allow some... */                       \\\n";
+
+my @allowed_ops = (
+	# basic set of opcodes
+	qw[:default :base_math !:base_io sort time],
+	# require is safe because we redirect the opcode
+	# entereval is safe as the opmask is now permanently set
+	# caller is safe because the entire interpreter is locked down
+	qw[require entereval caller],
+	# These are needed for utf8_heavy.pl:
+	# dofile is safe because we redirect the opcode like require above
+	# print is safe because the only writable filehandles are STDOUT & STDERR
+	# prtf (printf) is safe as it's the same as print + sprintf
+	qw[dofile print prtf],
+	# Disallow these opcodes that are in the :base_orig optag
+	# (included in :default) but aren't considered sufficiently safe
+	qw[!dbmopen !setpgrp !setpriority],
+);
+
+if (grep { /^custom$/ } opset_to_ops(full_opset) ) {
+	# custom is not deemed a likely security risk as it can't be generated from
+	# perl so would only be seen if the DBA had chosen to load a module that
+	# used it. Even then it's unlikely to be seen because it's typically
+	# generated by compiler plugins that operate after PL_op_mask checks.
+	# But we err on the side of caution and disable it, if it is actually
+	# defined.
+	push(@allowed_ops,qw[!custom]);
+}
+
+printf $fh "  /* ALLOWED: @allowed_ops */ \\\n";
+
+foreach my $opname (opset_to_ops(opset(@allowed_ops))) {
+	printf $fh qq{  opmask[OP_%-12s] = 0;\t/* %s */ \\\n},
+		uc($opname), opdesc($opname);
+}
+printf $fh "  /* end */ \n";
+
+close $fh
+	or die "Error closing $plperl_opmask_tmp: $!";
+
+rename $plperl_opmask_tmp, $plperl_opmask_h
+	or die "Error renaming $plperl_opmask_tmp to $plperl_opmask_h: $!";
+
+exit 0;

src/pl/plperl/sql/plperl.sql

@@ -361,3 +361,8 @@ CREATE OR REPLACE FUNCTION perl_spi_prepared_bad(double precision) RETURNS doubl
 $$ LANGUAGE plperl;
 SELECT perl_spi_prepared_bad(4.35) as "double precision";
 
+--
+-- Test detection of unsafe operations
+CREATE OR REPLACE FUNCTION perl_unsafe1() RETURNS void AS $$
+	my $fd = fileno STDERR;
+$$ LANGUAGE plperl;

src/pl/plperl/sql/plperlu_plperl.sql

+--
+-- Test that recursing between plperl and plperlu doesn't allow plperl to perform unsafe ops
+--
+
+-- recurse between a plperl and plperlu function that are identical except that
+-- each calls the other. Each also checks if an unsafe opcode can be executed.
+
+CREATE OR REPLACE FUNCTION recurse_plperl(i int) RETURNS SETOF TEXT LANGUAGE plperl
+AS $$
+	my $i = shift;
+	return unless $i > 0;
+	return_next "plperl  $i entry: ".((eval "stat;1") ? "ok" : $@);
+	return_next $_
+		for map { $_->{recurse_plperlu} }
+			@{spi_exec_query("select * from recurse_plperlu($i-1)")->{rows}};
+	return;
+$$;
+
+CREATE OR REPLACE FUNCTION recurse_plperlu(i int) RETURNS SETOF TEXT LANGUAGE plperlu
+AS $$
+	my $i = shift;
+	return unless $i > 0;
+	return_next "plperlu $i entry: ".((eval "stat;1") ? "ok" : $@);
+	return_next $_
+		for map { $_->{recurse_plperl} }
+			@{spi_exec_query("select * from recurse_plperl($i-1)")->{rows}};
+	return;
+$$;
+
+SELECT * FROM recurse_plperl(5);
+SELECT * FROM recurse_plperlu(5);
+
+--
+-- Make sure we can't use/require things in plperl
+--
+
+CREATE OR REPLACE FUNCTION use_plperlu() RETURNS void LANGUAGE plperlu
+AS $$
+use Errno;
+$$;
+
+CREATE OR REPLACE FUNCTION use_plperl() RETURNS void LANGUAGE plperl
+AS $$
+use Errno;
+$$;
+
+-- make sure our overloaded require op gets restored/set correctly
+select use_plperlu();
+
+CREATE OR REPLACE FUNCTION use_plperl() RETURNS void LANGUAGE plperl
+AS $$
+use Errno;
+$$;