diff --git a/src/parser.c b/src/parser.c
index ba816c8a4a..0cd03e0940 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -1151,7 +1151,7 @@ parse_specifier (GLogItem * logitem, char **str, const char *p, const char *end)
     if (!(tkn = parse_string (&(*str), end, 1)))
       return spec_err (logitem, SPEC_TOKN_NUL, *p, NULL);
 
-    if (invalid_protocol (tkn)) {
+    if (!invalid_protocol (tkn)) {
       spec_err (logitem, SPEC_TOKN_INV, *p, tkn);
       free (tkn);
       return 1;