Re: [PATCH] crypto: ccp: reduce stack usage in ccp_run_aes_gcm_cmd

[Tom Lendacky]

On 7/14/25 09:59, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@xxxxxxxx>
> 
> A number of functions in this file have large structures on the stack,
> ccp_run_aes_gcm_cmd() being the worst, in particular when KASAN
> is enabled on gcc:
> 
> drivers/crypto/ccp/ccp-ops.c: In function 'ccp_run_sha_cmd':
> drivers/crypto/ccp/ccp-ops.c:1833:1: error: the frame size of 1136 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
> drivers/crypto/ccp/ccp-ops.c: In function 'ccp_run_aes_gcm_cmd':
> drivers/crypto/ccp/ccp-ops.c:914:1: error: the frame size of 1632 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
> 
> Avoid the issue by using dynamic memory allocation in the worst one
> of these.
> 
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Acked-by: Tom Lendacky <thomas.lendacky@xxxxxxx>

> ---
> I'm not overly happy with this patch myself but couldn't come up
> with anything better either.
> 
> One alternative would be to turn off sanitizers here, but even without
> those, the stack usage is fairly high, so that still feels like
> papering over the problem.
> ---