From: Michael Brown <mcb30@ipxe.org>
Date: Mon, 15 Jul 2013 16:06:41 +0000 (+0200)
Subject: [script] Avoid trying to read final character of a zero-length string
X-Git-Tag: v1.20.1~1466
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e52c24492af3465657fef882e15da9bc80e3512a;p=thirdparty%2Fipxe.git

[script] Avoid trying to read final character of a zero-length string

Detected using Valgrind.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
---

diff --git a/src/image/script.c b/src/image/script.c
index 8ef058545..ceccd9018 100644
--- a/src/image/script.c
+++ b/src/image/script.c
@@ -92,11 +92,11 @@ static int process_script ( struct image *image,
 		script_offset += ( frag_len + 1 );
 
 		/* Strip trailing CR, if present */
-		if ( line[ len - 1 ] == '\r' )
+		if ( len && ( line[ len - 1 ] == '\r' ) )
 			len--;
 
 		/* Handle backslash continuations */
-		if ( line[ len - 1 ] == '\\' ) {
+		if ( len && ( line[ len - 1 ] == '\\' ) ) {
 			len--;
 			rc = -EINVAL;
 			continue;