Check for invalid keyslot in keyslot_only_active

src/api/encryption_keys_delete.c

@@ -21,8 +21,17 @@ char * keyslot_only_active(struct crypt_device * cd, const int keyslot,
     for (i = 0; i < keyslot_max; i++)
     {
         // If it's not the given one, check if it's active.
-        if (i != keyslot && crypt_keyslot_status(cd, i) != CRYPT_SLOT_INACTIVE)
+        crypt_keyslot_info s = crypt_keyslot_status(cd, i);
+        if (s == CRYPT_SLOT_INVALID)
         {
+            char * error;
+            asprintf(&error, "crypt_keyslot_info: invalid keyslot %d", i);
+            return error;
+        }
+
+        if (i != keyslot && (s == CRYPT_SLOT_ACTIVE || s == CRYPT_SLOT_ACTIVE_LAST))
+        {
+            // We found a keyslot other than the given one that's active.
             *only_active = false;
             return NULL;
         }