On Mon, Aug 19, 2019 at 06:25:41PM +0300, Jarkko Sakkinen wrote:
> Instead of looping through the array of reserved bytes use memchr_inv()
> to check the bytes.
>
> Cc: Sean Christopherson <sean.j.christpherson@xxxxxxxxx>
> Cc: Shay Katz-zamir <shay.katz-zamir@xxxxxxxxx>
> Cc: Serge Ayoun <serge.ayoun@xxxxxxxxx>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> ---
> arch/x86/kernel/cpu/sgx/driver/ioctl.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/sgx/driver/ioctl.c b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
> index 64d3286f3324..d5f326411df0 100644
> --- a/arch/x86/kernel/cpu/sgx/driver/ioctl.c
> +++ b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
> @@ -414,7 +414,6 @@ static int sgx_validate_secinfo(struct sgx_secinfo *secinfo)
> {
> u64 page_type = secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK;
> u64 perm = secinfo->flags & SGX_SECINFO_PERMISSION_MASK;
> - int i;
>
> if ((secinfo->flags & SGX_SECINFO_RESERVED_MASK) ||
> ((perm & SGX_SECINFO_W) && !(perm & SGX_SECINFO_R)) ||
> @@ -422,9 +421,8 @@ static int sgx_validate_secinfo(struct sgx_secinfo *secinfo)
> page_type != SGX_SECINFO_REG))
> return -EINVAL;
>
> - for (i = 0; i < SGX_SECINFO_RESERVED_SIZE; i++)
> - if (secinfo->reserved[i])
> - return -EINVAL;
> + if (memchr_inv(secinfo->reserved, 0, SGX_SECINFO_RESERVED_SIZE))
Doing 'sizeof(secinfo->reserved)' would be preferable, that way we're not
dependent on SGX_SECINFO_RESERVED_SIZE being in bytes (I had to check).
Obviously not in this patch, but the same cleanup can be applied to
sgx_validate_secs().
> + return -EINVAL;
>
> return 0;
> }
> --
> 2.20.1
>
