diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index f5569f005cf3..17eec39e775e 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1241,9 +1241,9 @@ static char *get_kernel_version(const char *root_dir)
 		return NULL;
 
 	tmp = fgets(version, sizeof(version), file);
-	if (!tmp)
-		*version = '\0';
 	fclose(file);
+	if (!tmp)
+		return NULL;
 
 	name = strstr(version, prefix);
 	if (!name)