Re: [PATCH v5 10/13] x86/xsaves: Fix __fpu_restore_sig() for XSAVES

From: Dave Hansen
Date: Mon May 09 2016 - 19:43:59 EST


On 05/09/2016 01:46 PM, Yu-cheng Yu wrote:
> When the kernel is using XSAVES compacted format, we cannot do
> __copy_from_user() from a signal frame, which has standard-format data.
> Fix it by using copyin_to_xsaves().
... which converts between formats and filters out all supervisor state,
which we do not want to allow userspace to write.

Reviewed-by: Dave Hansen <dave.hansen@xxxxxxxxx>