Re: [PATCH v8 1/2] crypto: AF_ALG: add AEAD support

[Herbert Xu]

On Wed, Jan 07, 2015 at 04:51:38PM +0100, Stephan Mueller wrote:
>
> +		if (!aead_writable(sk)) {
> +			/*
> +			 * If there is more data to be expected, but we cannot
> +			 * write more data, forcefully define that we do not
> +			 * expect more data to invoke the AEAD operation. This
> +			 * prevents a deadlock in user space.
> +			 */
> +			ctx->more = 0;

We should return EMSGSIZE here.  Also we should clear out the
existing data so that the socket may be reused again.

> +	ctx->more = msg->msg_flags & MSG_MORE;
> +	if (!ctx->more && !aead_sufficient_data(ctx))
> +		err = -EINVAL;

Ditto, we should discard the data that's queued up.  Also perhaps
use EBADMSG instead of EINVAL.

> +	/*
> +	 * Require exactly one IOV block as the AEAD operation is a one shot
> +	 * due to the authentication tag.
> +	 */
> +	if (msg->msg_iter.nr_segs != 1)
> +		return -ENOMSG;

Why does the receive buffer have to be contiguous?

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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