Fix a potential out-of-bounds read caused by the big-endian fix.

We must store a UTF-32 empty string, not UTF-8 empty string, for
an empty CCL.  Found running the awk test suite with address sanitizer.

diff --git a/usr.bin/awk/b.c b/usr.bin/awk/b.c
index 64284ab..5cf54ab 100644 (file)
--- a/usr.bin/awk/b.c
+++ b/usr.bin/awk/b.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: b.c,v 1.41 2023/09/19 01:14:05 millert Exp $  */
+/*     $OpenBSD: b.c,v 1.42 2023/09/21 17:19:06 millert Exp $  */
 /****************************************************************
 Copyright (C) Lucent Technologies 1997
 All Rights Reserved
@@ -951,7 +951,7 @@ Node *primary(void)
                rtok = relex();
                if (rtok == ')') {      /* special pleading for () */
                        rtok = relex();
-                       return unary(op2(CCL, NIL, (Node *) tostring("")));
+                       return unary(op2(CCL, NIL, (Node *) cclenter("")));
                }
                np = regexp();
                if (rtok == ')') {
@@ -974,7 +974,7 @@ Node *concat(Node *np)
                return (concat(op2(CAT, np, primary())));
        case EMPTYRE:
                rtok = relex();
-               return (concat(op2(CAT, op2(CCL, NIL, (Node *) tostring("")),
+               return (concat(op2(CAT, op2(CCL, NIL, (Node *) cclenter("")),
                                primary())));
        }
        return (np);