KVM: SVM: Add intercept checks for descriptor table accesses

This patch add intercept checks into the KVM instruction
emulator to check for the 8 instructions that access the
descriptor table addresses.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index cd9ed9f45275..3ac830a135fd 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2630,8 +2630,18 @@ static struct opcode group5[] = {
         D(SrcMem | ModRM | Stack), N,
 };
 
+static struct opcode group6[] = {
+        DI(ModRM | Prot,        sldt),
+        DI(ModRM | Prot,        str),
+        DI(ModRM | Prot | Priv, lldt),
+        DI(ModRM | Prot | Priv, ltr),
+        N, N, N, N,
+};
+
 static struct group_dual group7 = { {
-        N, N, DI(ModRM | SrcMem | Priv, lgdt), DI(ModRM | SrcMem | Priv, lidt),
+        DI(ModRM | Mov | DstMem | Priv, sgdt),
+        DI(ModRM | Mov | DstMem | Priv, sidt),
+        DI(ModRM | SrcMem | Priv, lgdt), DI(ModRM | SrcMem | Priv, lidt),
         DI(SrcNone | ModRM | DstMem | Mov, smsw), N,
         DI(SrcMem16 | ModRM | Mov | Priv, lmsw),
         DI(SrcMem | ModRM | ByteOp | Priv | NoAccess, invlpg),
@@ -2766,7 +2776,7 @@ static struct opcode opcode_table[256] = {
 
 static struct opcode twobyte_table[256] = {
         /* 0x00 - 0x0F */
-        N, GD(0, &group7), N, N,
+        G(0, group6), GD(0, &group7), N, N,
         N, D(ImplicitOps | VendorSpecific), DI(ImplicitOps | Priv, clts), N,
         DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N,
         N, D(ImplicitOps | ModRM), N, N,