[GIT PULL] Asymmetric keys fix for v6.4-rc5

[David Howells]

Roberto Sassu <roberto.sassu at huaweicloud.com> wrote:

> Here is a small fix to make an unconditional copy of the buffer passed
> to crypto operations, to take into account the case of the stack not in
> the linear mapping area.

I wonder if evm_verify_hmac() and other such callers of the signature
verification service should be placing the data and crypto material in slab
memory rather than it being on the stack.  But, for the moment:

Acked-by: David Howells <dhowells at redhat.com>