On Tue, 2017-06-27 at 03:11 -0700, Ram Pai wrote: > x86 does not support disabling execute permissions on a pkey. > > Signed-off-by: Ram Pai <linux...@us.ibm.com> > --- > arch/x86/kernel/fpu/xstate.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c > index c24ac1e..d582631 100644 > --- a/arch/x86/kernel/fpu/xstate.c > +++ b/arch/x86/kernel/fpu/xstate.c > @@ -900,6 +900,9 @@ int arch_set_user_pkey_access(struct task_struct *tsk, > int pkey, > if (!boot_cpu_has(X86_FEATURE_OSPKE)) > return -EINVAL; > > + if (init_val & PKEY_DISABLE_EXECUTE) > + return -EINVAL; > + > /* Set the bits we need in PKRU: */ > if (init_val & PKEY_DISABLE_ACCESS) > new_pkru_bits |= PKRU_AD_BIT;
I am not an x86 expert. IIUC, execute disable is done via allocating an execute_only_pkey and checking vma_key via AD + vma_flags against VM_EXEC. Your patch looks good to me Acked-by: Balbir Singh <bsinghar...@gmail.com> Balbir Singh.
