File kerberos-fallback-bso15789.patch of Package samba

--- source3/libsmb/cliconnect.c	2025-12-12 16:19:32.000000000 +0000
+++ source3/libsmb/cliconnect.c	2025-12-30 23:41:04.687932060 +0000
@@ -218,7 +218,7 @@ struct cli_credentials *cli_session_cred
 				goto fail;
 			}
 		}
-	} else if (use_kerberos && !fallback_after_kerberos) {
+	} else if (use_kerberos) {
 		const char *error_string = NULL;
 		int rc;

--- auth/credentials/credentials.c	2025-12-12 16:19:32.000000000 +0000
+++ auth/credentials/credentials.c	2025-12-30 23:44:35.612014784 +0000
@@ -563,6 +563,10 @@ _PUBLIC_ bool cli_credentials_authentica
 		return true;
 	}
 
+	if (cli_credentials_get_kerberos_state(cred) == CRED_USE_KERBEROS_DESIRED) {
+		return true;
+	}
+
 	gensec_features = cli_credentials_get_gensec_features(cred);
 	if (gensec_features & GENSEC_FEATURE_NTLM_CCACHE) {
 		return true;