Fix recovery of realloc failure, which causes a segv on files with

very lone lines, as reported by Steffen Wendzel.  ok deraadt@

1 files changed, 12 insertions, 8 deletions

diff --git a/usr.bin/less/line.c b/usr.bin/less/line.c
index bd82f504c20..3c6a906a92d 100644
--- a/usr.bin/less/line.c
+++ b/usr.bin/less/line.c
@@ -80,14 +80,18 @@ init_line()
 expand_linebuf()
 {
 	int new_size = size_linebuf * 2;
-	char *new_buf = (char *) realloc(linebuf, new_size);
-	char *new_attr = (char *) realloc(attr, new_size);
-	if (new_buf == NULL || new_attr == NULL)
-	{
-		if (new_attr != NULL)
-			free(new_attr);
-		if (new_buf != NULL)
-			free(new_buf);
+	char *new_buf;
+	char *new_attr;
+
+	new_buf = realloc(linebuf, new_size);
+	if (new_buf == NULL)
+		return 1;
+	new_attr = realloc(attr, new_size);
+	if (new_attr == NULL) {
+		/* realloc linebuf back to original size */
+		linebuf = realloc(new_buf, size_linebuf);
+		if (linebuf == NULL)
+			err(1, NULL);
 		return 1;
 	}
 	memset(new_buf + size_linebuf, 0, new_size - size_linebuf);