alsactl: Fix potential NULL dereferences in daemon mode

The code releasing the each card object may access to NULL when a
bogus count is given.  Add a NULL check just to make sure.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/alsactl/daemon.c b/alsactl/daemon.c
index 127701efaf0fdf59dc8adfd336018056e7d50906..4f0a935a3987bd603035d1482d7d173eeb17e0b7 100644 (file)
--- a/alsactl/daemon.c
+++ b/alsactl/daemon.c
@@ -451,8 +451,10 @@ save:
 out:
        free(pfd);
        remove(pidfile);
-       for (i = 0; i < count; i++)
-               card_free(&cards[i]);
-       free(cards);
+       if (cards) {
+               for (i = 0; i < count; i++)
+                       card_free(&cards[i]);
+               free(cards);
+       }
        return 0;
 }