From: Radu Greab <radu@netsoft.ro>
Date: Mon, 2 Oct 2000 22:03:44 +0000 (+0300)
Subject: Re: [ID 20000912.008] substr replacement of tainted data (bug)
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=35fba0d9b63c24c469494ae4d5dc6f37fed89345;p=p5sagit%2Fp5-mst-13.2.git

Re: [ID 20000912.008] substr replacement of tainted data (bug)
Message-ID: <14808.56336.594486.626712@busy.netsoft.ro>

p4raw-id: //depot/perl@7111
---

diff --git a/op.c b/op.c
index 4856d98..84a1df9 100644
--- a/op.c
+++ b/op.c
@@ -6463,6 +6463,22 @@ Perl_ck_trunc(pTHX_ OP *o)
     return ck_fun(o);
 }
 
+OP *
+Perl_ck_substr(pTHX_ OP *o)
+{
+    o = ck_fun(o);
+    if ((o->op_flags & OPf_KIDS) && o->op_private == 4) {
+	OP *kid = cLISTOPo->op_first;
+
+	if (kid->op_type == OP_NULL)
+	    kid = kid->op_sibling;
+	if (kid)
+	    kid->op_flags |= OPf_MOD;
+
+    }
+    return o;
+}
+
 /* A peephole optimizer.  We visit the ops in the order they're to execute. */
 
 void
diff --git a/opcode.pl b/opcode.pl
index d138917..43d98ae 100755
--- a/opcode.pl
+++ b/opcode.pl
@@ -515,7 +515,7 @@ abs		abs			ck_fun		fsTu%	S?
 # String stuff.
 
 length		length			ck_lengthconst	isTu%	S?
-substr		substr			ck_fun		st@	S S S? S?
+substr		substr			ck_substr	st@	S S S? S?
 vec		vec			ck_fun		ist@	S S S
 
 index		index			ck_index	isT@	S S S?
diff --git a/t/op/substr.t b/t/op/substr.t
index 891e904..4d3bbce 100755
--- a/t/op/substr.t
+++ b/t/op/substr.t
@@ -1,6 +1,6 @@
 #!./perl
 
-print "1..135\n";
+print "1..136\n";
 
 #P = start of string  Q = start of substr  R = end of substr  S = end of string
 
@@ -297,3 +297,10 @@ ok 125, $a eq 'xxxxefgh';
     ok 134, length($z) == 5;
     ok 135, $z eq "21\x{263a}10";
 }
+
+# replacement should work on magical values
+require Tie::Scalar;
+my %data;
+tie $data{'a'}, 'Tie::StdScalar';  # makes $data{'a'} magical
+$data{a} = "firstlast";
+ok 136, substr($data{'a'}, 0, 5, "") eq "first" && $data{'a'} eq "last";