On Monday, December 30, 2013 05:01:13 PM Herbert Xu wrote:

On Fri, Dec 27, 2013 at 01:21:36AM +0100, Marek Vasut wrote:

quoted

quoted

quoted

-	complete(data, err);
+	areq->base.complete = complete;
+	areq->base.data = data;
+
+	complete(&areq->base, err);

This looks completely bogus.  While restoring areq isn't wrong per
se, calling complete with &areq->base makes no sense.  The original
completion data is in the variable "data".

Is there some documentation for this so I can understand why this is wrong, 
please? I really don't quite get it, sorry. Actually, is there some 
documentation for writing crypto API drivers at all please ?

Well it's wrong because the completion function (req->base.complete)
is meant to take data (req->base.data) as its first argument.  So
giving it a pointer to req->base makes no sense.

The crypto_completion_t typdef is defined as:

typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err);

so I believe &areq->base is the proper first argument (which is actually just
the req parameter on the ahash_op_unaligned_done function).

If you are going to restore areq, you really should restore all fields that
were changed - result, base.complete, base.data - and set priv to NULL.

Since the ahash_request_priv structure is freed in ahash_op_unaligned_finish
you'll need to save the value of priv->result in order to restore areq->result
(u8 *result = priv->result; or similar).

Additionally, you should probably also fix up ahash_def_finup_done2 and
ahash_def_finup_done1.

Thanks,
Tom

Cheers,