Re: [PATCH] crypto: aesni - Use unaligned loads from gcm_context_data
From: Herbert Xu
Date: Sat Aug 25 2018 - 09:28:17 EST
On Wed, Aug 15, 2018 at 10:29:42AM -0700, Dave Watson wrote:
> A regression was reported bisecting to 1476db2d12
> "Move HashKey computation from stack to gcm_context". That diff
> moved HashKey computation from the stack, which was explicitly aligned
> in the asm, to a struct provided from the C code, depending on
> AESNI_ALIGN_ATTR for alignment. It appears some compilers may not
> align this struct correctly, resulting in a crash on the movdqa
> instruction when attempting to encrypt or decrypt data.
> Fix by using unaligned loads for the HashKeys. On modern
> hardware there is no perf difference between the unaligned and
> aligned loads. All other accesses to gcm_context_data already use
> unaligned loads.
> Reported-by: Mauro Rossi <issor.oruam@xxxxxxxxx>
> Fixes: 1476db2d12 ("Move HashKey computation from stack to gcm_context")
> Signed-off-by: Dave Watson <davejwatson@xxxxxx>
Patch applied. Thanks.
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt