Messages in this thread | | | Subject | Re: [PATCH v19 02/25] x86/cet/shstk: Add Kconfig option for user-mode control-flow protection | From | "Yu, Yu-cheng" <> | Date | Thu, 4 Feb 2021 16:05:04 -0800 |
| |
On 2/4/2021 11:56 AM, Kees Cook wrote: > On Wed, Feb 03, 2021 at 02:55:24PM -0800, Yu-cheng Yu wrote: >> Shadow Stack provides protection against function return address >> corruption. It is active when the processor supports it, the kernel has >> CONFIG_X86_CET enabled, and the application is built for the feature. >> This is only implemented for the 64-bit kernel. When it is enabled, legacy >> non-Shadow Stack applications continue to work, but without protection. >> >> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com> >> --- >> arch/x86/Kconfig | 22 ++++++++++++++++++++++ >> arch/x86/Kconfig.assembler | 5 +++++ >> 2 files changed, 27 insertions(+) >> >> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig >> index 21f851179ff0..074b3c0e6bf6 100644 >> --- a/arch/x86/Kconfig >> +++ b/arch/x86/Kconfig >> @@ -1951,6 +1951,28 @@ config X86_SGX >> >> If unsure, say N. >> >> +config ARCH_HAS_SHADOW_STACK >> + def_bool n >> + >> +config X86_CET >> + prompt "Intel Control-flow protection for user-mode" >> + def_bool n >> + depends on X86_64 >> + depends on AS_WRUSS >> + select ARCH_USES_HIGH_VMA_FLAGS >> + select ARCH_HAS_SHADOW_STACK > > This seems backwards to me? Shouldn't 'config X86_64' do the 'select > ARCH_HAS_SHADOW_STACK' and 'config X86_CET' do a 'depends on > ARCH_HAS_SHADOW_STACK' instead?
I will change it. Thanks!
-- Yu-cheng
| |