[PATCH -next v3 2/2] powerpc: add support for syscall stack randomization

[Kees Cook]

On Fri, Jul 01, 2022 at 04:24:35PM +0800, Xiu Jianfeng wrote:
> Add support for adding a random offset to the stack while handling
> syscalls. This patch uses mftb() instead of get_random_int() for better
> performance.
> 
> In order to avoid unconditional stack canaries on syscall entry (due to
> the use of alloca()), also disable stack protector to avoid triggering
> needless checks and slowing down the entry path. As there is no general
> way to control stack protector coverage with a function attribute, this
> must be disabled at the compilation unit level.
> 
> Signed-off-by: Xiu Jianfeng <xiujianfeng at huawei.com>

Reviewed-by: Kees Cook <keescook at chromium.org>

-Kees

-- 
Kees Cook