diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index f364b085397e..60c2a4efad4a 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -211,8 +211,9 @@ static int filter_pred_pchar(struct filter_pred *pred, void *event,
 {
 	char **addr = (char **)(event + pred->offset);
 	int cmp, match;
+	int len = strlen(*addr) + 1;	/* including tailing '\0' */
 
-	cmp = pred->regex.match(*addr, &pred->regex, pred->regex.field_len);
+	cmp = pred->regex.match(*addr, &pred->regex, len);
 
 	match = cmp ^ pred->not;
 
@@ -782,10 +783,8 @@ static int filter_add_pred(struct filter_parse_state *ps,
 			pred->regex.field_len = field->size;
 		} else if (field->filter_type == FILTER_DYN_STRING)
 			fn = filter_pred_strloc;
-		else {
+		else
 			fn = filter_pred_pchar;
-			pred->regex.field_len = strlen(pred->regex.pattern);
-		}
 	} else {
 		if (field->is_signed)
 			ret = strict_strtoll(pred->regex.pattern, 0, &val);