isdn: guard against a potential NULL pointer dereference in old_capi_manufacturer()

[cascardo/linux.git] / drivers / isdn / capi / kcapi.c

diff --git a/drivers/isdn/capi/kcapi.c b/drivers/isdn/capi/kcapi.c
index 9f73bc2..f555318 100644 (file)
--- a/drivers/isdn/capi/kcapi.c
+++ b/drivers/isdn/capi/kcapi.c
@@ -821,6 +821,8 @@ static int old_capi_manufacturer(unsigned int cmd, void __user *data)
                                return -EFAULT;
                }
                card = get_capi_ctr_by_nr(ldef.contr);
+               if (!card)
+                       return -EINVAL;
                card = capi_ctr_get(card);
                if (!card)
                        return -ESRCH;