ucm: add NULL check for card_name in open

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/src/ucm/main.c b/src/ucm/main.c
index ed6d1c94b41a55861705001657a5c2f68c779f9f..30ab1e4151f07cfaa8a4fa67379f99633e50862c 100644 (file)
--- a/src/ucm/main.c
+++ b/src/ucm/main.c
@@ -1518,7 +1518,7 @@ int snd_use_case_mgr_open(snd_use_case_mgr_t **uc_mgr,
                mgr->suppress_nodev_errors = 1;
        }
 
-       if (card_name[0] == '<' && card_name[1] == '<' && card_name[2] == '<')
+       if (card_name && card_name[0] == '<' && card_name[1] == '<' && card_name[2] == '<')
                card_name = parse_open_variables(mgr, card_name);
 
        err = uc_mgr_card_open(mgr);