Fix invalid write in yylex.

3 files changed, 10 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 13468de2..7017741f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2015-10-25         Arnold D. Robbins     <arnold@skeeve.com>
+
+	* awkgram.y (yylex): Fix invalid write problems.
+	Reported by Hanno Boeck <hanno@hboeck.de>.
+	Only appeared in master. Harumph.
+
 2015-10-16         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* Makefile.am (SUBDIRS): Fix ordering so that
diff --git a/awkgram.c b/awkgram.c
index f8f80ad5..b37ee57a 100644
--- a/awkgram.c
+++ b/awkgram.c
@@ -4736,7 +4736,8 @@ yyerror(const char *m, ...)
 	count = strlen(mesg) + 1;
 	if (lexptr != NULL)
 		count += (lexeme - thisline) + 2;
-	emalloc(buf, char *, count, "yyerror");
+	emalloc(buf, char *, count+1, "yyerror");
+	memset(buf, 0, count+1);
 
 	bp = buf;
 
diff --git a/awkgram.y b/awkgram.y
index 88f5e209..7805f144 100644
--- a/awkgram.y
+++ b/awkgram.y
@@ -2316,7 +2316,8 @@ yyerror(const char *m, ...)
 	count = strlen(mesg) + 1;
 	if (lexptr != NULL)
 		count += (lexeme - thisline) + 2;
-	emalloc(buf, char *, count, "yyerror");
+	emalloc(buf, char *, count+1, "yyerror");
+	memset(buf, 0, count+1);
 
 	bp = buf;