diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
index 27420159bf6944df76eb76a45943a4810e0ba972..8a9a677f75768205c47343c126813808e564a38a 100644
--- a/tools/perf/util/trace-event-read.c
+++ b/tools/perf/util/trace-event-read.c
@@ -192,7 +192,7 @@ static int read_ftrace_printk(struct pevent *pevent)
 	if (!size)
 		return 0;
 
-	buf = malloc(size);
+	buf = malloc(size + 1);
 	if (buf == NULL)
 		return -1;
 
@@ -201,6 +201,8 @@ static int read_ftrace_printk(struct pevent *pevent)
 		return -1;
 	}
 
+	buf[size] = '\0';
+
 	parse_ftrace_printk(pevent, buf, size);
 
 	free(buf);