Re: [PATCH v2 1/6] crypto: Use memzero_explicit() for clearing state

Herbert Xu
2020-10-23T20:45:50Z

On Fri, Oct 23, 2020 at 08:56:04AM -0700, Eric Biggers wrote:
>
> When clearing memory because "it may be sensitive" rather than "it's needed for
> the code to behave correctly", I think it's best to use memzero_explicit() to
> make the intent clear, even if it seems that memset() is sufficient. Also keep
> in mind that support for compiling the kernel with LTO (link-time optimization)
> is being worked on (and some people already do it), which results in more code
> being optimized out.

The rule up until now has been that we only use memzero_explicit for
stack variables. At this point please don't convert anything else
as it will cause too much churn.

If LTO did arrive we should do a global conversion.

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