Re: [PATCH 5/7] staging: usbip: Add encryption support to kernel

[Dan Carpenter <dan.carpenter@oracle.com>]

On Thu, Sep 19, 2013 at 04:11:57PM +0200, Dominik Paulus wrote:
> +int usbip_init_crypto(struct usbip_device *ud, unsigned char *sendkey, unsigned
> +		char *recvkey)
> +{
> +	int ret;
> +
> +	ud->use_crypto = 1;
> +
> +	ud->tfm_recv = crypto_alloc_aead("gcm(aes)", 0, 0);
> +	if (IS_ERR(ud->tfm_recv))
> +		return -PTR_ERR(ud->tfm_recv);
> +	ud->tfm_send = crypto_alloc_aead("gcm(aes)", 0, 0);
> +	if (IS_ERR(ud->tfm_send)) {
> +		crypto_free_aead(ud->tfm_recv);
> +		return -PTR_ERR(ud->tfm_send);
> +	}
> +	ret = kfifo_alloc(&ud->recv_queue, RECVQ_SIZE, GFP_KERNEL);
> +	if (ret) {
> +		crypto_free_aead(ud->tfm_recv);
> +		crypto_free_aead(ud->tfm_send);
> +		return ret;
> +	}
> +
> +	if (crypto_aead_setkey(ud->tfm_send, sendkey, USBIP_KEYSIZE) != 0 ||
> +			crypto_aead_setkey(ud->tfm_recv, recvkey,
> +				USBIP_KEYSIZE) != 0 ||
> +			crypto_aead_setauthsize(ud->tfm_send,
> +				USBIP_AUTHSIZE) != 0 ||
> +			crypto_aead_setauthsize(ud->tfm_recv,
> +				USBIP_AUTHSIZE)) {
> +		crypto_free_aead(ud->tfm_recv);
> +		crypto_free_aead(ud->tfm_send);
> +		kfifo_free(&ud->recv_queue);
> +	}

This returns success on error instead of failure.

The indenting is messed up.  There are three places which check " != 0"
and doesn't.  Please leave off the "!= 0" throughout the whole patch.
It should look like:

	if (crypto_aead_setkey(ud->tfm_send, sendkey, USBIP_KEYSIZE) ||
	    crypto_aead_setkey(ud->tfm_recv, recvkey, USBIP_KEYSIZE) ||
	    crypto_aead_setauthsize(ud->tfm_send, USBIP_AUTHSIZE) ||
	    crypto_aead_setauthsize(ud->tfm_recv, USBIP_AUTHSIZE)) {
	    	ret = -EINVAL;
		goto err_free_fifo;
	}

Notice how the label name is chosen based on the label location and not
the goto location.

The end of the function should look like:

	return 0;

err_free_fifo:
	kfifo_free(&ud->recv_queue);
err_free_send:
	crypto_free_aead(ud->tfm_send);
err_free_recv:
	crypto_free_aead(ud->tfm_recv);

	return ret;

regards,
dan carpenter