@@ -94,6 +94,7 @@
#define VM_EXIT_CLEAR_BNDCFGS 0x00800000
#define VM_EXIT_PT_CONCEAL_PIP 0x01000000
#define VM_EXIT_CLEAR_IA32_RTIT_CTL 0x02000000
+#define VM_EXIT_LOAD_HOST_CET_STATE 0x10000000
#define VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR 0x00036dff
@@ -107,6 +108,7 @@
#define VM_ENTRY_LOAD_BNDCFGS 0x00010000
#define VM_ENTRY_PT_CONCEAL_PIP 0x00020000
#define VM_ENTRY_LOAD_IA32_RTIT_CTL 0x00040000
+#define VM_ENTRY_LOAD_GUEST_CET_STATE 0x00100000
#define VM_ENTRY_ALWAYSON_WITHOUT_TRUE_MSR 0x000011ff
@@ -328,6 +330,9 @@ enum vmcs_field {
GUEST_PENDING_DBG_EXCEPTIONS = 0x00006822,
GUEST_SYSENTER_ESP = 0x00006824,
GUEST_SYSENTER_EIP = 0x00006826,
+ GUEST_S_CET = 0x00006828,
+ GUEST_SSP = 0x0000682a,
+ GUEST_INTR_SSP_TABLE = 0x0000682c,
HOST_CR0 = 0x00006c00,
HOST_CR3 = 0x00006c02,
HOST_CR4 = 0x00006c04,
@@ -340,6 +345,9 @@ enum vmcs_field {
HOST_IA32_SYSENTER_EIP = 0x00006c12,
HOST_RSP = 0x00006c14,
HOST_RIP = 0x00006c16,
+ HOST_S_CET = 0x00006c18,
+ HOST_SSP = 0x00006c1a,
+ HOST_INTR_SSP_TABLE = 0x00006c1c
};
/*
@@ -31,6 +31,7 @@
#define MC_VECTOR 18
#define XM_VECTOR 19
#define VE_VECTOR 20
+#define CP_VECTOR 21
/* Select x86 specific features in <linux/kvm.h> */
#define __KVM_HAVE_PIT
@@ -186,6 +186,9 @@ static struct kvm_shared_msrs __percpu *shared_msrs;
| XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \
| XFEATURE_MASK_PKRU)
+#define KVM_SUPPORTED_XSS (XFEATURE_MASK_CET_USER | \
+ XFEATURE_MASK_CET_KERNEL)
+
u64 __read_mostly host_efer;
EXPORT_SYMBOL_GPL(host_efer);
@@ -402,6 +405,7 @@ static int exception_class(int vector)
case NP_VECTOR:
case SS_VECTOR:
case GP_VECTOR:
+ case CP_VECTOR:
return EXCPT_CONTRIBUTORY;
default:
break;
@@ -115,7 +115,7 @@ static inline bool x86_exception_has_error_code(unsigned int vector)
{
static u32 exception_has_error_code = BIT(DF_VECTOR) | BIT(TS_VECTOR) |
BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) |
- BIT(PF_VECTOR) | BIT(AC_VECTOR);
+ BIT(PF_VECTOR) | BIT(AC_VECTOR) | BIT(CP_VECTOR);
return (1U << vector) & exception_has_error_code;
}
CET(Control-flow Enforcement Technology) is a CPU feature used to prevent Return/Jump-Oriented Programming(ROP/JOP) attacks. It provides the following sub-features to defend against ROP/JOP style control-flow subversion attacks: Shadow Stack (SHSTK): A second stack for program which is used exclusively for control transfer operations. Indirect Branch Tracking (IBT): Code branching protection to defend against jump/call oriented programming. Several new CET MSRs are defined in kernel to support CET: MSR_IA32_{U,S}_CET: Controls the CET settings for user mode and suervisor mode respectively. MSR_IA32_PL{0,1,2,3}_SSP: Stores shadow stack pointers for CPL-0,1,2,3 level respectively. MSR_IA32_INT_SSP_TAB: Stores base address of shadow stack pointer table. Two XSAVES state bits are introduced for CET: IA32_XSS:[bit 11]: For saving/restoring user mode CET states IA32_XSS:[bit 12]: For saving/restoring supervisor mode CET states. Six VMCS fields are introduced for CET: {HOST,GUEST}_S_CET: Stores CET settings for supervisor mode. {HOST,GUEST}_SSP: Stores shadow stack pointer for supervisor mode. {HOST,GUEST}_INTR_SSP_TABLE: Stores base address of shadow stack pointer table. If VM_EXIT_LOAD_HOST_CET_STATE = 1, the host's CET MSRs are restored from below VMCS fields at VM-Exit: HOST_S_CET HOST_SSP HOST_INTR_SSP_TABLE If VM_ENTRY_LOAD_GUEST_CET_STATE = 1, the guest's CET MSRs are loaded from below VMCS fields at VM-Entry: GUEST_S_CET GUEST_SSP GUEST_INTR_SSP_TABLE Co-developed-by: Zhang Yi Z <yi.z.zhang@linux.intel.com> Signed-off-by: Zhang Yi Z <yi.z.zhang@linux.intel.com> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com> --- arch/x86/include/asm/vmx.h | 8 ++++++++ arch/x86/include/uapi/asm/kvm.h | 1 + arch/x86/kvm/x86.c | 4 ++++ arch/x86/kvm/x86.h | 2 +- 4 files changed, 14 insertions(+), 1 deletion(-)