On Sat, Mar 28, 2020 at 09:43:03AM -0700, Yu-cheng Yu wrote:
> The function sanitize_restored_xstate() sanitizes user xstates of an XSAVE
> buffer by setting the buffer's header->xfeatures to the input 'xfeatures',
It doesn't set them to the input xfeatures. I see a "&=" there.
> effectively resetting features not in 'xfeatures' back to the init state.
>
> When supervisor xstates are introduced, it is necessary to make sure only
> user xstates are sanitized. Ensure supervisor bits in header->xfeatures
> stay set and supervisor states are not modified.
>
> To make names clear, also:
>
> - Rename the function to sanitize_restored_user_xstate().
> - Rename input parameter 'xfeatures' to 'xfeatures_from_user'.
> - In __fpu__restore_sig(), rename 'xfeatures' to 'user_xfeatures'.
>
> v3:
> - Change xfeatures_user to user_xfeatures.
>
> Signed-off-by: Yu-cheng Yu <yu-cheng...@intel.com>
> Reviewed-by: Dave Hansen <dave.han...@linux.intel.com>
> ---
> arch/x86/kernel/fpu/signal.c | 37 +++++++++++++++++++++++-------------
> 1 file changed, 24 insertions(+), 13 deletions(-)
>
> diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
> index cd6eafba12da..d09d72334a12 100644
> --- a/arch/x86/kernel/fpu/signal.c
> +++ b/arch/x86/kernel/fpu/signal.c
> @@ -211,9 +211,9 @@ int copy_fpstate_to_sigframe(void __user *buf, void
> __user *buf_fx, int size)
> }
>
> static inline void
> -sanitize_restored_xstate(union fpregs_state *state,
> - struct user_i387_ia32_struct *ia32_env,
> - u64 xfeatures, int fx_only)
> +sanitize_restored_user_xstate(union fpregs_state *state,
> + struct user_i387_ia32_struct *ia32_env,
> + u64 xfeatures_from_user, int fx_only)
Name those user_xfeatures too.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
