diff --git a/src/proto_tcp.c b/src/proto_tcp.c
index ea75866..9c0dc37 100644
--- a/src/proto_tcp.c
+++ b/src/proto_tcp.c
@@ -1392,7 +1392,7 @@
 			}
 			else {
 				/* Custom keywords. */
-				if (rule->action_ptr)
+				if (!rule->action_ptr)
 					break;
 				switch (rule->action_ptr(rule, sess->fe, sess, NULL, ACT_FLAG_FINAL | ACT_FLAG_FIRST)) {
 				case ACT_RET_YIELD: