diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d5f7c4d..063a92b 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -843,9 +843,12 @@
 	if (isspace(ch)) {
 		parser->buffer[parser->idx] = 0;
 		parser->cont = false;
-	} else {
+	} else if (parser->idx < parser->size - 1) {
 		parser->cont = true;
 		parser->buffer[parser->idx++] = ch;
+	} else {
+		ret = -EINVAL;
+		goto out;
 	}
 
 	*ppos += read;