static int nfc_genl_dep_link_up(struct sk_buff *skb, struct genl_info *info)
{
	struct nfc_dev *dev;
	int rc, tgt_idx;
	u32 idx;
	u8 comm;

	pr_debug("DEP link up\n");

	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
	    !info->attrs[NFC_ATTR_COMM_MODE])
		return -EINVAL;

	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
	if (!info->attrs[NFC_ATTR_TARGET_INDEX])
		tgt_idx = NFC_TARGET_IDX_ANY;
	else
		tgt_idx = nla_get_u32(info->attrs[NFC_ATTR_TARGET_INDEX]);

	comm = nla_get_u8(info->attrs[NFC_ATTR_COMM_MODE]);

	if (comm != NFC_COMM_ACTIVE && comm != NFC_COMM_PASSIVE)
		return -EINVAL;

	dev = nfc_get_device(idx);
	if (!dev)
		return -ENODEV;

	rc = nfc_dep_link_up(dev, tgt_idx, comm);

	nfc_put_device(dev);

	return rc;
}

The product dereferences a pointer that it expects to be valid but is NULL.