[dm-devel] [PATCH 0/17] crypto: api - Change completion callback argument to void star

[Herbert Xu]

On Mon, Feb 06, 2023 at 11:10:08PM -0800, Jakub Kicinski wrote:
> On Mon, 6 Feb 2023 18:21:06 +0800 Herbert Xu wrote:
> > The crypto completion function currently takes a pointer to a
> > struct crypto_async_request object.  However, in reality the API
> > does not allow the use of any part of the object apart from the
> > data field.  For example, ahash/shash will create a fake object
> > on the stack to pass along a different data field.
> 
> "different data field" == copy the value to a different structure?
> A bit hard to parse TBH.

The word data here refers to the data field in struct crypto_async_request.
 
> Buggy means bug could be hit in real light or buggy == did not use 
> the API right?

Yes this bug is real.  If you hit a driver/algorithm that returns
a different request object (of which there are many in the API) then
you will be dereferencing random pointers.

Cheers,
-- 
Email: Herbert Xu <herbert at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt