Re: [PATCH] crypto: lrw - Only add ecb if it is not already there

[Herbert Xu <herbert@gondor.apana.org.au>]

On Thu, May 15, 2025 at 01:04:55PM -0700, Eric Biggers wrote:
>
> It didn't actually make a difference until 795f85fca229 ("crypto: algboss - Pass
> instance creation error up") though, right?  Before then, if "ecb(...)" gave
> ENOENT then "ecb(ecb(...))" gave ENOENT too.

I would consider this a success, it actually caught lrw doing
something silly by trying to allocate "ecb(ecb(XXX))".  Sure we
can sweep all of this under the rug with ENOENT but it might end
up blowing up in a much worse place.

Also I don't think it's true that ecb(ecb(XXX)) will always give an
ENOENT if ecb(XXX) gives an ENOENT.  The error is actually originating
from the lskcipher code, which tries to construct ecb from either an
lskcipher, or a simple cipher.  It is the latter that triggers the
EINVAL error since the ecb template cannot create a simple cipher.

> As I said in
> https://lore.kernel.org/linux-crypto/20240924222839.GC1585@sol.localdomain/,
> that commit (which had no explanation) just seems wrong.  We should have simply
> stuck with ENOENT.
> 
> But as usual my concern just got ignored and it got pushed out anyway.

I don't ignore all your concerns, just the ones that I think are
unwarranted :)

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