diff options
| author | Fenghua Yu <fenghua.yu@intel.com> | 2011-05-17 18:44:26 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2011-05-17 20:56:59 -0700 |
| commit | d0281a257f370b09c410e466571858b4e12869c9 (patch) | |
| tree | 87d48822fbbf0325fdd140d1bcd868ad8c230456 /arch/x86/include/asm/cpufeature.h | |
| parent | 724a92ee45c04cb9d82884a856b03b1e594d9de1 (diff) | |
x86, cpufeature: Add cpufeature flag for SMEP
Add support for newly documented SMEP (Supervisor Mode Execution Protection) CPU
feature flag.
SMEP prevents the CPU in kernel-mode to jump to an executable page
that has the user flag set in the PTE. This prevents the kernel from
executing user-space code accidentally or maliciously, so it for
example prevents kernel exploits from jumping to specially prepared
user-mode shell code.
[ hpa: added better description by Ingo Molnar ]
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
LKML-Reference: <1305683069-25394-2-git-send-email-fenghua.yu@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/include/asm/cpufeature.h')
| -rw-r--r-- | arch/x86/include/asm/cpufeature.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 7f2f7b123293..8808cdb96c3f 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -195,6 +195,7 @@ /* Intel-defined CPU features, CPUID level 0x00000007:0 (ebx), word 9 */ #define X86_FEATURE_FSGSBASE (9*32+ 0) /* {RD/WR}{FS/GS}BASE instructions*/ +#define X86_FEATURE_SMEP (9*32+ 7) /* Supervisor Mode Execution Protection */ #define X86_FEATURE_ERMS (9*32+ 9) /* Enhanced REP MOVSB/STOSB */ #if defined(__KERNEL__) && !defined(__ASSEMBLY__) |