From 4d4ec0874583b127caac1d0f84033c8971b2fd2a Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Tue, 29 Dec 2009 18:07:30 +0200
Subject: KVM: Replace read accesses of vcpu->arch.cr0 by an accessor

Since we'd like to allow the guest to own a few bits of cr0 at times, we need
to know when we access those bits.

Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 7e8faea4651e..0f89e320bc96 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1515,7 +1515,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt)
 
 	/* syscall is not available in real mode */
 	if (c->lock_prefix || ctxt->mode == X86EMUL_MODE_REAL
-		|| !(ctxt->vcpu->arch.cr0 & X86_CR0_PE))
+	    || !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE))
 		return -1;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
@@ -1569,7 +1569,7 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 
 	/* inject #GP if in real mode or paging is disabled */
 	if (ctxt->mode == X86EMUL_MODE_REAL ||
-		!(ctxt->vcpu->arch.cr0 & X86_CR0_PE)) {
+	    !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE)) {
 		kvm_inject_gp(ctxt->vcpu, 0);
 		return -1;
 	}
@@ -1635,7 +1635,7 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 
 	/* inject #GP if in real mode or paging is disabled */
 	if (ctxt->mode == X86EMUL_MODE_REAL
-		|| !(ctxt->vcpu->arch.cr0 & X86_CR0_PE)) {
+	    || !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE)) {
 		kvm_inject_gp(ctxt->vcpu, 0);
 		return -1;
 	}
-- 
cgit v1.2.3


From b60d513c32e2ddc8b3e9e1465b94913d44d19810 Mon Sep 17 00:00:00 2001
From: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Date: Wed, 20 Jan 2010 16:47:21 +0900
Subject: KVM: x86: Use macros for x86_emulate_ops to avoid future mistakes

The return values from x86_emulate_ops are defined
in kvm_emulate.h as macros X86EMUL_*.

But in emulate.c, we are comparing the return values
from these ops with 0 to check if they're X86EMUL_CONTINUE
or not: X86EMUL_CONTINUE is defined as 0 now.

To avoid possible mistakes in the future, this patch
substitutes "X86EMUL_CONTINUE" for "0" that are being
compared with the return values from x86_emulate_ops.

  We think that there are more places we should use these
  macros, but the meanings of rc values in x86_emulate_insn()
  were not so clear at a glance. If we use proper macros in
  this function, we would be able to follow the flow of each
  emulation more easily and, maybe, more securely.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---
 arch/x86/kvm/emulate.c | 65 ++++++++++++++++++++++++++++----------------------
 1 file changed, 36 insertions(+), 29 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 0f89e320bc96..48c7f9f8a08f 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1196,7 +1196,7 @@ static int emulate_pop(struct x86_emulate_ctxt *ctxt,
 	rc = ops->read_emulated(register_address(c, ss_base(ctxt),
 						 c->regs[VCPU_REGS_RSP]),
 				dest, len, ctxt->vcpu);
-	if (rc != 0)
+	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
 	register_address_increment(c, &c->regs[VCPU_REGS_RSP], len);
@@ -1370,7 +1370,7 @@ static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt,
 	int rc;
 
 	rc = ops->read_emulated(memop, &old, 8, ctxt->vcpu);
-	if (rc != 0)
+	if (rc != X86EMUL_CONTINUE)
 		return rc;
 
 	if (((u32) (old >> 0) != (u32) c->regs[VCPU_REGS_RAX]) ||
@@ -1385,7 +1385,7 @@ static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt,
 		       (u32) c->regs[VCPU_REGS_RBX];
 
 		rc = ops->cmpxchg_emulated(memop, &old, &new, 8, ctxt->vcpu);
-		if (rc != 0)
+		if (rc != X86EMUL_CONTINUE)
 			return rc;
 		ctxt->eflags |= EFLG_ZF;
 	}
@@ -1451,7 +1451,7 @@ static inline int writeback(struct x86_emulate_ctxt *ctxt,
 					&c->dst.val,
 					c->dst.bytes,
 					ctxt->vcpu);
-		if (rc != 0)
+		if (rc != X86EMUL_CONTINUE)
 			return rc;
 		break;
 	case OP_NONE:
@@ -1749,7 +1749,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 					&c->src.val,
 					c->src.bytes,
 					ctxt->vcpu);
-		if (rc != 0)
+		if (rc != X86EMUL_CONTINUE)
 			goto done;
 		c->src.orig_val = c->src.val;
 	}
@@ -1768,12 +1768,15 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 			c->dst.ptr = (void *)c->dst.ptr +
 						   (c->src.val & mask) / 8;
 		}
-		if (!(c->d & Mov) &&
-				   /* optimisation - avoid slow emulated read */
-		    ((rc = ops->read_emulated((unsigned long)c->dst.ptr,
-					   &c->dst.val,
-					  c->dst.bytes, ctxt->vcpu)) != 0))
-			goto done;
+		if (!(c->d & Mov)) {
+			/* optimisation - avoid slow emulated read */
+			rc = ops->read_emulated((unsigned long)c->dst.ptr,
+						&c->dst.val,
+						c->dst.bytes,
+						ctxt->vcpu);
+			if (rc != X86EMUL_CONTINUE)
+				goto done;
+		}
 	}
 	c->dst.orig_val = c->dst.val;
 
@@ -2039,11 +2042,12 @@ special_insn:
 		c->dst.ptr = (unsigned long *)register_address(c,
 						   es_base(ctxt),
 						   c->regs[VCPU_REGS_RDI]);
-		if ((rc = ops->read_emulated(register_address(c,
-					   seg_override_base(ctxt, c),
-					c->regs[VCPU_REGS_RSI]),
+		rc = ops->read_emulated(register_address(c,
+						seg_override_base(ctxt, c),
+						c->regs[VCPU_REGS_RSI]),
 					&c->dst.val,
-					c->dst.bytes, ctxt->vcpu)) != 0)
+					c->dst.bytes, ctxt->vcpu);
+		if (rc != X86EMUL_CONTINUE)
 			goto done;
 		register_address_increment(c, &c->regs[VCPU_REGS_RSI],
 				       (ctxt->eflags & EFLG_DF) ? -c->dst.bytes
@@ -2058,10 +2062,11 @@ special_insn:
 		c->src.ptr = (unsigned long *)register_address(c,
 				       seg_override_base(ctxt, c),
 						   c->regs[VCPU_REGS_RSI]);
-		if ((rc = ops->read_emulated((unsigned long)c->src.ptr,
-						&c->src.val,
-						c->src.bytes,
-						ctxt->vcpu)) != 0)
+		rc = ops->read_emulated((unsigned long)c->src.ptr,
+					&c->src.val,
+					c->src.bytes,
+					ctxt->vcpu);
+		if (rc != X86EMUL_CONTINUE)
 			goto done;
 
 		c->dst.type = OP_NONE; /* Disable writeback. */
@@ -2069,10 +2074,11 @@ special_insn:
 		c->dst.ptr = (unsigned long *)register_address(c,
 						   es_base(ctxt),
 						   c->regs[VCPU_REGS_RDI]);
-		if ((rc = ops->read_emulated((unsigned long)c->dst.ptr,
-						&c->dst.val,
-						c->dst.bytes,
-						ctxt->vcpu)) != 0)
+		rc = ops->read_emulated((unsigned long)c->dst.ptr,
+					&c->dst.val,
+					c->dst.bytes,
+					ctxt->vcpu);
+		if (rc != X86EMUL_CONTINUE)
 			goto done;
 
 		DPRINTF("cmps: mem1=0x%p mem2=0x%p\n", c->src.ptr, c->dst.ptr);
@@ -2102,12 +2108,13 @@ special_insn:
 		c->dst.type = OP_REG;
 		c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
 		c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX];
-		if ((rc = ops->read_emulated(register_address(c,
-						 seg_override_base(ctxt, c),
-						 c->regs[VCPU_REGS_RSI]),
-						 &c->dst.val,
-						 c->dst.bytes,
-						 ctxt->vcpu)) != 0)
+		rc = ops->read_emulated(register_address(c,
+						seg_override_base(ctxt, c),
+						c->regs[VCPU_REGS_RSI]),
+					&c->dst.val,
+					c->dst.bytes,
+					ctxt->vcpu);
+		if (rc != X86EMUL_CONTINUE)
 			goto done;
 		register_address_increment(c, &c->regs[VCPU_REGS_RSI],
 				       (ctxt->eflags & EFLG_DF) ? -c->dst.bytes
-- 
cgit v1.2.3


From 3eeb3288bcbf64da90afc26389b8844df7c34912 Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Thu, 21 Jan 2010 15:31:48 +0200
Subject: KVM: Add a helper for checking if the guest is in protected mode

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---
 arch/x86/kvm/emulate.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 48c7f9f8a08f..6a429eefc533 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -32,6 +32,7 @@
 #include <linux/module.h>
 #include <asm/kvm_emulate.h>
 
+#include "x86.h"
 #include "mmu.h"		/* for is_long_mode() */
 
 /*
@@ -1515,7 +1516,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt)
 
 	/* syscall is not available in real mode */
 	if (c->lock_prefix || ctxt->mode == X86EMUL_MODE_REAL
-	    || !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE))
+	    || !is_protmode(ctxt->vcpu))
 		return -1;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
@@ -1568,8 +1569,7 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 		return -1;
 
 	/* inject #GP if in real mode or paging is disabled */
-	if (ctxt->mode == X86EMUL_MODE_REAL ||
-	    !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE)) {
+	if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) {
 		kvm_inject_gp(ctxt->vcpu, 0);
 		return -1;
 	}
@@ -1634,8 +1634,7 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 		return -1;
 
 	/* inject #GP if in real mode or paging is disabled */
-	if (ctxt->mode == X86EMUL_MODE_REAL
-	    || !kvm_read_cr0_bits(ctxt->vcpu, X86_CR0_PE)) {
+	if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) {
 		kvm_inject_gp(ctxt->vcpu, 0);
 		return -1;
 	}
-- 
cgit v1.2.3


From 836a1b3c3456042704c86aaa3d837b976de9343b Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Thu, 21 Jan 2010 15:31:49 +0200
Subject: KVM: Move cr0/cr4/efer related helpers to x86.h

They have more general scope than the mmu.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---
 arch/x86/kvm/emulate.c | 1 -
 1 file changed, 1 deletion(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 6a429eefc533..645b245a3c23 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -33,7 +33,6 @@
 #include <asm/kvm_emulate.h>
 
 #include "x86.h"
-#include "mmu.h"		/* for is_long_mode() */
 
 /*
  * Opcode effective-address decode tables.
-- 
cgit v1.2.3


From 2db2c2eb6226e30f8059b82512a1364db98da8e3 Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:29 +0200
Subject: KVM: x86 emulator: Add group8 instruction decoding

Use groups mechanism to decode 0F BA instructions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 645b245a3c23..435b1e4e8c9b 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -88,6 +88,7 @@
 enum {
 	Group1_80, Group1_81, Group1_82, Group1_83,
 	Group1A, Group3_Byte, Group3, Group4, Group5, Group7,
+	Group8,
 };
 
 static u32 opcode_table[256] = {
@@ -267,7 +268,7 @@ static u32 twobyte_table[256] = {
 	0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov,
 	    DstReg | SrcMem16 | ModRM | Mov,
 	/* 0xB8 - 0xBF */
-	0, 0, DstMem | SrcImmByte | ModRM, DstMem | SrcReg | ModRM | BitOp,
+	0, 0, Group | Group8, DstMem | SrcReg | ModRM | BitOp,
 	0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov,
 	    DstReg | SrcMem16 | ModRM | Mov,
 	/* 0xC0 - 0xCF */
@@ -323,6 +324,10 @@ static u32 group_table[] = {
 	0, 0, ModRM | SrcMem, ModRM | SrcMem,
 	SrcNone | ModRM | DstMem | Mov, 0,
 	SrcMem16 | ModRM | Mov, SrcMem | ModRM | ByteOp,
+	[Group8*8] =
+	0, 0, 0, 0,
+	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
+	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
 };
 
 static u32 group2_table[] = {
-- 
cgit v1.2.3


From 60a29d4ea4e7b6b95d9391ebc8625b0426f3a363 Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:30 +0200
Subject: KVM: x86 emulator: Add group9 instruction decoding

Use groups mechanism to decode 0F C7 instructions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 435b1e4e8c9b..45a4f7c1bb0b 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -88,7 +88,7 @@
 enum {
 	Group1_80, Group1_81, Group1_82, Group1_83,
 	Group1A, Group3_Byte, Group3, Group4, Group5, Group7,
-	Group8,
+	Group8, Group9,
 };
 
 static u32 opcode_table[256] = {
@@ -272,7 +272,8 @@ static u32 twobyte_table[256] = {
 	0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov,
 	    DstReg | SrcMem16 | ModRM | Mov,
 	/* 0xC0 - 0xCF */
-	0, 0, 0, DstMem | SrcReg | ModRM | Mov, 0, 0, 0, ImplicitOps | ModRM,
+	0, 0, 0, DstMem | SrcReg | ModRM | Mov,
+	0, 0, 0, Group | GroupDual | Group9,
 	0, 0, 0, 0, 0, 0, 0, 0,
 	/* 0xD0 - 0xDF */
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
@@ -328,6 +329,8 @@ static u32 group_table[] = {
 	0, 0, 0, 0,
 	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
 	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
+	[Group9*8] =
+	0, ImplicitOps | ModRM, 0, 0, 0, 0, 0, 0,
 };
 
 static u32 group2_table[] = {
@@ -335,6 +338,8 @@ static u32 group2_table[] = {
 	SrcNone | ModRM, 0, 0, SrcNone | ModRM,
 	SrcNone | ModRM | DstMem | Mov, 0,
 	SrcMem16 | ModRM | Mov, 0,
+	[Group9*8] =
+	0, 0, 0, 0, 0, 0, 0, 0,
 };
 
 /* EFLAGS bit definitions. */
-- 
cgit v1.2.3


From a0044755679f3e761b8b95995e5f2db2b7efd0f6 Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:31 +0200
Subject: KVM: x86 emulator: Add Virtual-8086 mode of emulation

For some instructions CPU behaves differently for real-mode and
virtual 8086. Let emulator know which mode cpu is in, so it will
not poke into vcpu state directly.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 45a4f7c1bb0b..e4e2df3b6038 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -899,6 +899,7 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 
 	switch (mode) {
 	case X86EMUL_MODE_REAL:
+	case X86EMUL_MODE_VM86:
 	case X86EMUL_MODE_PROT16:
 		def_op_bytes = def_ad_bytes = 2;
 		break;
@@ -1525,7 +1526,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt)
 
 	/* syscall is not available in real mode */
 	if (c->lock_prefix || ctxt->mode == X86EMUL_MODE_REAL
-	    || !is_protmode(ctxt->vcpu))
+	    || ctxt->mode == X86EMUL_MODE_VM86)
 		return -1;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
@@ -1577,8 +1578,8 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 	if (c->lock_prefix)
 		return -1;
 
-	/* inject #GP if in real mode or paging is disabled */
-	if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) {
+	/* inject #GP if in real mode */
+	if (ctxt->mode == X86EMUL_MODE_REAL) {
 		kvm_inject_gp(ctxt->vcpu, 0);
 		return -1;
 	}
@@ -1642,8 +1643,9 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 	if (c->lock_prefix)
 		return -1;
 
-	/* inject #GP if in real mode or paging is disabled */
-	if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) {
+	/* inject #GP if in real mode or Virtual 8086 mode */
+	if (ctxt->mode == X86EMUL_MODE_REAL ||
+	    ctxt->mode == X86EMUL_MODE_VM86) {
 		kvm_inject_gp(ctxt->vcpu, 0);
 		return -1;
 	}
-- 
cgit v1.2.3


From 1871c6020d7308afb99127bba51f04548e7ca84e Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:32 +0200
Subject: KVM: x86 emulator: fix memory access during x86 emulation

Currently when x86 emulator needs to access memory, page walk is done with
broadest permission possible, so if emulated instruction was executed
by userspace process it can still access kernel memory. Fix that by
providing correct memory access to page walker during emulation.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index e4e2df3b6038..c44b46014842 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -616,7 +616,7 @@ static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt,
 
 	if (linear < fc->start || linear >= fc->end) {
 		size = min(15UL, PAGE_SIZE - offset_in_page(linear));
-		rc = ops->read_std(linear, fc->data, size, ctxt->vcpu);
+		rc = ops->fetch(linear, fc->data, size, ctxt->vcpu, NULL);
 		if (rc)
 			return rc;
 		fc->start = linear;
@@ -671,11 +671,11 @@ static int read_descriptor(struct x86_emulate_ctxt *ctxt,
 		op_bytes = 3;
 	*address = 0;
 	rc = ops->read_std((unsigned long)ptr, (unsigned long *)size, 2,
-			   ctxt->vcpu);
+			   ctxt->vcpu, NULL);
 	if (rc)
 		return rc;
 	rc = ops->read_std((unsigned long)ptr + 2, address, op_bytes,
-			   ctxt->vcpu);
+			   ctxt->vcpu, NULL);
 	return rc;
 }
 
-- 
cgit v1.2.3


From f850e2e603bf5a05b0aee7901857cf85715aa694 Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:33 +0200
Subject: KVM: x86 emulator: Check IOPL level during io instruction emulation

Make emulator check that vcpu is allowed to execute IN, INS, OUT,
OUTS, CLI, STI.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 82 insertions(+), 7 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index c44b46014842..296e8519dc53 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1698,6 +1698,57 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 	return 0;
 }
 
+static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt)
+{
+	int iopl;
+	if (ctxt->mode == X86EMUL_MODE_REAL)
+		return false;
+	if (ctxt->mode == X86EMUL_MODE_VM86)
+		return true;
+	iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
+	return kvm_x86_ops->get_cpl(ctxt->vcpu) > iopl;
+}
+
+static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt,
+					    struct x86_emulate_ops *ops,
+					    u16 port, u16 len)
+{
+	struct kvm_segment tr_seg;
+	int r;
+	u16 io_bitmap_ptr;
+	u8 perm, bit_idx = port & 0x7;
+	unsigned mask = (1 << len) - 1;
+
+	kvm_get_segment(ctxt->vcpu, &tr_seg, VCPU_SREG_TR);
+	if (tr_seg.unusable)
+		return false;
+	if (tr_seg.limit < 103)
+		return false;
+	r = ops->read_std(tr_seg.base + 102, &io_bitmap_ptr, 2, ctxt->vcpu,
+			  NULL);
+	if (r != X86EMUL_CONTINUE)
+		return false;
+	if (io_bitmap_ptr + port/8 > tr_seg.limit)
+		return false;
+	r = ops->read_std(tr_seg.base + io_bitmap_ptr + port/8, &perm, 1,
+			  ctxt->vcpu, NULL);
+	if (r != X86EMUL_CONTINUE)
+		return false;
+	if ((perm >> bit_idx) & mask)
+		return false;
+	return true;
+}
+
+static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt,
+				 struct x86_emulate_ops *ops,
+				 u16 port, u16 len)
+{
+	if (emulator_bad_iopl(ctxt))
+		if (!emulator_io_port_access_allowed(ctxt, ops, port, len))
+			return false;
+	return true;
+}
+
 int
 x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 {
@@ -1889,7 +1940,12 @@ special_insn:
 		break;
 	case 0x6c:		/* insb */
 	case 0x6d:		/* insw/insd */
-		 if (kvm_emulate_pio_string(ctxt->vcpu,
+		if (!emulator_io_permited(ctxt, ops, c->regs[VCPU_REGS_RDX],
+					  (c->d & ByteOp) ? 1 : c->op_bytes)) {
+			kvm_inject_gp(ctxt->vcpu, 0);
+			goto done;
+		}
+		if (kvm_emulate_pio_string(ctxt->vcpu,
 				1,
 				(c->d & ByteOp) ? 1 : c->op_bytes,
 				c->rep_prefix ?
@@ -1905,6 +1961,11 @@ special_insn:
 		return 0;
 	case 0x6e:		/* outsb */
 	case 0x6f:		/* outsw/outsd */
+		if (!emulator_io_permited(ctxt, ops, c->regs[VCPU_REGS_RDX],
+					  (c->d & ByteOp) ? 1 : c->op_bytes)) {
+			kvm_inject_gp(ctxt->vcpu, 0);
+			goto done;
+		}
 		if (kvm_emulate_pio_string(ctxt->vcpu,
 				0,
 				(c->d & ByteOp) ? 1 : c->op_bytes,
@@ -2202,7 +2263,13 @@ special_insn:
 	case 0xef: /* out (e/r)ax,dx */
 		port = c->regs[VCPU_REGS_RDX];
 		io_dir_in = 0;
-	do_io:	if (kvm_emulate_pio(ctxt->vcpu, io_dir_in,
+	do_io:
+		if (!emulator_io_permited(ctxt, ops, port,
+					  (c->d & ByteOp) ? 1 : c->op_bytes)) {
+			kvm_inject_gp(ctxt->vcpu, 0);
+			goto done;
+		}
+		if (kvm_emulate_pio(ctxt->vcpu, io_dir_in,
 				   (c->d & ByteOp) ? 1 : c->op_bytes,
 				   port) != 0) {
 			c->eip = saved_eip;
@@ -2227,13 +2294,21 @@ special_insn:
 		c->dst.type = OP_NONE;	/* Disable writeback. */
 		break;
 	case 0xfa: /* cli */
-		ctxt->eflags &= ~X86_EFLAGS_IF;
-		c->dst.type = OP_NONE;	/* Disable writeback. */
+		if (emulator_bad_iopl(ctxt))
+			kvm_inject_gp(ctxt->vcpu, 0);
+		else {
+			ctxt->eflags &= ~X86_EFLAGS_IF;
+			c->dst.type = OP_NONE;	/* Disable writeback. */
+		}
 		break;
 	case 0xfb: /* sti */
-		toggle_interruptibility(ctxt, X86_SHADOW_INT_STI);
-		ctxt->eflags |= X86_EFLAGS_IF;
-		c->dst.type = OP_NONE;	/* Disable writeback. */
+		if (emulator_bad_iopl(ctxt))
+			kvm_inject_gp(ctxt->vcpu, 0);
+		else {
+			toggle_interruptibility(ctxt, X86_SHADOW_INT_STI);
+			ctxt->eflags |= X86_EFLAGS_IF;
+			c->dst.type = OP_NONE;	/* Disable writeback. */
+		}
 		break;
 	case 0xfc: /* cld */
 		ctxt->eflags &= ~EFLG_DF;
-- 
cgit v1.2.3


From d4c6a1549c056f1d817e8f6f2f97d8b44933472f Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:34 +0200
Subject: KVM: x86 emulator: Fix popf emulation

POPF behaves differently depending on current CPU mode. Emulate correct
logic to prevent guest from changing flags that it can't change otherwise.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 54 insertions(+), 1 deletion(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 296e8519dc53..1782387c069e 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -343,11 +343,18 @@ static u32 group2_table[] = {
 };
 
 /* EFLAGS bit definitions. */
+#define EFLG_ID (1<<21)
+#define EFLG_VIP (1<<20)
+#define EFLG_VIF (1<<19)
+#define EFLG_AC (1<<18)
 #define EFLG_VM (1<<17)
 #define EFLG_RF (1<<16)
+#define EFLG_IOPL (3<<12)
+#define EFLG_NT (1<<14)
 #define EFLG_OF (1<<11)
 #define EFLG_DF (1<<10)
 #define EFLG_IF (1<<9)
+#define EFLG_TF (1<<8)
 #define EFLG_SF (1<<7)
 #define EFLG_ZF (1<<6)
 #define EFLG_AF (1<<4)
@@ -1214,6 +1221,49 @@ static int emulate_pop(struct x86_emulate_ctxt *ctxt,
 	return rc;
 }
 
+static int emulate_popf(struct x86_emulate_ctxt *ctxt,
+		       struct x86_emulate_ops *ops,
+		       void *dest, int len)
+{
+	int rc;
+	unsigned long val, change_mask;
+	int iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
+	int cpl = kvm_x86_ops->get_cpl(ctxt->vcpu);
+
+	rc = emulate_pop(ctxt, ops, &val, len);
+	if (rc != X86EMUL_CONTINUE)
+		return rc;
+
+	change_mask = EFLG_CF | EFLG_PF | EFLG_AF | EFLG_ZF | EFLG_SF | EFLG_OF
+		| EFLG_TF | EFLG_DF | EFLG_NT | EFLG_RF | EFLG_AC | EFLG_ID;
+
+	switch(ctxt->mode) {
+	case X86EMUL_MODE_PROT64:
+	case X86EMUL_MODE_PROT32:
+	case X86EMUL_MODE_PROT16:
+		if (cpl == 0)
+			change_mask |= EFLG_IOPL;
+		if (cpl <= iopl)
+			change_mask |= EFLG_IF;
+		break;
+	case X86EMUL_MODE_VM86:
+		if (iopl < 3) {
+			kvm_inject_gp(ctxt->vcpu, 0);
+			return X86EMUL_PROPAGATE_FAULT;
+		}
+		change_mask |= EFLG_IF;
+		break;
+	default: /* real mode */
+		change_mask |= (EFLG_IOPL | EFLG_IF);
+		break;
+	}
+
+	*(unsigned long *)dest =
+		(ctxt->eflags & ~change_mask) | (val & change_mask);
+
+	return rc;
+}
+
 static void emulate_push_sreg(struct x86_emulate_ctxt *ctxt, int seg)
 {
 	struct decode_cache *c = &ctxt->decode;
@@ -2099,7 +2149,10 @@ special_insn:
 		c->dst.type = OP_REG;
 		c->dst.ptr = (unsigned long *) &ctxt->eflags;
 		c->dst.bytes = c->op_bytes;
-		goto pop_instruction;
+		rc = emulate_popf(ctxt, ops, &c->dst.val, c->op_bytes);
+		if (rc != X86EMUL_CONTINUE)
+			goto done;
+		break;
 	case 0xa0 ... 0xa1:	/* mov */
 		c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX];
 		c->dst.val = c->src.val;
-- 
cgit v1.2.3


From e92805ac1228626c59c865f2f4e9059b9fb8c97b Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:35 +0200
Subject: KVM: x86 emulator: Check CPL level during privilege instruction
 emulation

Add CPL checking in case emulator is tricked into emulating
privilege instruction from userspace.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 35 ++++++++++++++++++++---------------
 1 file changed, 20 insertions(+), 15 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 1782387c069e..d63211169ac1 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -76,6 +76,7 @@
 #define GroupDual   (1<<15)     /* Alternate decoding of mod == 3 */
 #define GroupMask   0xff        /* Group number stored in bits 0:7 */
 /* Misc flags */
+#define Priv        (1<<27) /* instruction generates #GP if current CPL != 0 */
 #define No64	    (1<<28)
 /* Source 2 operand type */
 #define Src2None    (0<<29)
@@ -211,7 +212,7 @@ static u32 opcode_table[256] = {
 	SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
 	/* 0xF0 - 0xF7 */
 	0, 0, 0, 0,
-	ImplicitOps, ImplicitOps, Group | Group3_Byte, Group | Group3,
+	ImplicitOps | Priv, ImplicitOps, Group | Group3_Byte, Group | Group3,
 	/* 0xF8 - 0xFF */
 	ImplicitOps, 0, ImplicitOps, ImplicitOps,
 	ImplicitOps, ImplicitOps, Group | Group4, Group | Group5,
@@ -219,16 +220,20 @@ static u32 opcode_table[256] = {
 
 static u32 twobyte_table[256] = {
 	/* 0x00 - 0x0F */
-	0, Group | GroupDual | Group7, 0, 0, 0, ImplicitOps, ImplicitOps, 0,
-	ImplicitOps, ImplicitOps, 0, 0, 0, ImplicitOps | ModRM, 0, 0,
+	0, Group | GroupDual | Group7, 0, 0,
+	0, ImplicitOps, ImplicitOps | Priv, 0,
+	ImplicitOps | Priv, ImplicitOps | Priv, 0, 0,
+	0, ImplicitOps | ModRM, 0, 0,
 	/* 0x10 - 0x1F */
 	0, 0, 0, 0, 0, 0, 0, 0, ImplicitOps | ModRM, 0, 0, 0, 0, 0, 0, 0,
 	/* 0x20 - 0x2F */
-	ModRM | ImplicitOps, ModRM, ModRM | ImplicitOps, ModRM, 0, 0, 0, 0,
+	ModRM | ImplicitOps | Priv, ModRM | Priv,
+	ModRM | ImplicitOps | Priv, ModRM | Priv,
+	0, 0, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0,
 	/* 0x30 - 0x3F */
-	ImplicitOps, 0, ImplicitOps, 0,
-	ImplicitOps, ImplicitOps, 0, 0,
+	ImplicitOps | Priv, 0, ImplicitOps | Priv, 0,
+	ImplicitOps, ImplicitOps | Priv, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0,
 	/* 0x40 - 0x47 */
 	DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
@@ -322,9 +327,9 @@ static u32 group_table[] = {
 	SrcMem | ModRM | Stack, 0,
 	SrcMem | ModRM | Stack, 0, SrcMem | ModRM | Stack, 0,
 	[Group7*8] =
-	0, 0, ModRM | SrcMem, ModRM | SrcMem,
+	0, 0, ModRM | SrcMem | Priv, ModRM | SrcMem | Priv,
 	SrcNone | ModRM | DstMem | Mov, 0,
-	SrcMem16 | ModRM | Mov, SrcMem | ModRM | ByteOp,
+	SrcMem16 | ModRM | Mov | Priv, SrcMem | ModRM | ByteOp | Priv,
 	[Group8*8] =
 	0, 0, 0, 0,
 	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
@@ -335,7 +340,7 @@ static u32 group_table[] = {
 
 static u32 group2_table[] = {
 	[Group7*8] =
-	SrcNone | ModRM, 0, 0, SrcNone | ModRM,
+	SrcNone | ModRM | Priv, 0, 0, SrcNone | ModRM,
 	SrcNone | ModRM | DstMem | Mov, 0,
 	SrcMem16 | ModRM | Mov, 0,
 	[Group9*8] =
@@ -1700,12 +1705,6 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 		return -1;
 	}
 
-	/* sysexit must be called from CPL 0 */
-	if (kvm_x86_ops->get_cpl(ctxt->vcpu) != 0) {
-		kvm_inject_gp(ctxt->vcpu, 0);
-		return -1;
-	}
-
 	setup_syscalls_segments(ctxt, &cs, &ss);
 
 	if ((c->rex_prefix & 0x8) != 0x0)
@@ -1820,6 +1819,12 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
 	saved_eip = c->eip;
 
+	/* Privileged instruction can be executed only in CPL=0 */
+	if ((c->d & Priv) && kvm_x86_ops->get_cpl(ctxt->vcpu)) {
+		kvm_inject_gp(ctxt->vcpu, 0);
+		goto done;
+	}
+
 	if (((c->d & ModRM) && (c->modrm_mod != 3)) || (c->d & MemAbs))
 		memop = c->modrm_ea;
 
-- 
cgit v1.2.3


From d380a5e4022a5c63a6c5ac631e48c752ba7f1e4f Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 10 Feb 2010 14:21:36 +0200
Subject: KVM: x86 emulator: Add LOCK prefix validity checking

Instructions which are not allowed to have LOCK prefix should
generate #UD if one is used.

[avi: fold opcode 82 fix from another patch]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 97 +++++++++++++++++++++++++++++---------------------
 1 file changed, 56 insertions(+), 41 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index d63211169ac1..c2de9f03da84 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -76,6 +76,7 @@
 #define GroupDual   (1<<15)     /* Alternate decoding of mod == 3 */
 #define GroupMask   0xff        /* Group number stored in bits 0:7 */
 /* Misc flags */
+#define Lock        (1<<26) /* lock prefix is allowed for the instruction */
 #define Priv        (1<<27) /* instruction generates #GP if current CPL != 0 */
 #define No64	    (1<<28)
 /* Source 2 operand type */
@@ -94,35 +95,35 @@ enum {
 
 static u32 opcode_table[256] = {
 	/* 0x00 - 0x07 */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
 	ByteOp | DstAcc | SrcImm, DstAcc | SrcImm,
 	ImplicitOps | Stack | No64, ImplicitOps | Stack | No64,
 	/* 0x08 - 0x0F */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
 	ByteOp | DstAcc | SrcImm, DstAcc | SrcImm,
 	ImplicitOps | Stack | No64, 0,
 	/* 0x10 - 0x17 */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
 	ByteOp | DstAcc | SrcImm, DstAcc | SrcImm,
 	ImplicitOps | Stack | No64, ImplicitOps | Stack | No64,
 	/* 0x18 - 0x1F */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
 	ByteOp | DstAcc | SrcImm, DstAcc | SrcImm,
 	ImplicitOps | Stack | No64, ImplicitOps | Stack | No64,
 	/* 0x20 - 0x27 */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
 	DstAcc | SrcImmByte, DstAcc | SrcImm, 0, 0,
 	/* 0x28 - 0x2F */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
 	0, 0, 0, 0,
 	/* 0x30 - 0x37 */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
 	0, 0, 0, 0,
 	/* 0x38 - 0x3F */
@@ -158,7 +159,7 @@ static u32 opcode_table[256] = {
 	Group | Group1_80, Group | Group1_81,
 	Group | Group1_82, Group | Group1_83,
 	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
 	/* 0x88 - 0x8F */
 	ByteOp | DstMem | SrcReg | ModRM | Mov, DstMem | SrcReg | ModRM | Mov,
 	ByteOp | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
@@ -263,17 +264,18 @@ static u32 twobyte_table[256] = {
 	DstMem | SrcReg | Src2CL | ModRM, 0, 0,
 	/* 0xA8 - 0xAF */
 	ImplicitOps | Stack, ImplicitOps | Stack,
-	0, DstMem | SrcReg | ModRM | BitOp,
+	0, DstMem | SrcReg | ModRM | BitOp | Lock,
 	DstMem | SrcReg | Src2ImmByte | ModRM,
 	DstMem | SrcReg | Src2CL | ModRM,
 	ModRM, 0,
 	/* 0xB0 - 0xB7 */
-	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, 0,
-	    DstMem | SrcReg | ModRM | BitOp,
+	ByteOp | DstMem | SrcReg | ModRM | Lock, DstMem | SrcReg | ModRM | Lock,
+	0, DstMem | SrcReg | ModRM | BitOp | Lock,
 	0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov,
 	    DstReg | SrcMem16 | ModRM | Mov,
 	/* 0xB8 - 0xBF */
-	0, 0, Group | Group8, DstMem | SrcReg | ModRM | BitOp,
+	0, 0,
+	Group | Group8, DstMem | SrcReg | ModRM | BitOp | Lock,
 	0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov,
 	    DstReg | SrcMem16 | ModRM | Mov,
 	/* 0xC0 - 0xCF */
@@ -290,25 +292,41 @@ static u32 twobyte_table[256] = {
 
 static u32 group_table[] = {
 	[Group1_80*8] =
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM,
 	[Group1_81*8] =
-	DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM,
-	DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM,
-	DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM,
-	DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM,
+	DstMem | SrcImm | ModRM | Lock,
+	DstMem | SrcImm | ModRM | Lock,
+	DstMem | SrcImm | ModRM | Lock,
+	DstMem | SrcImm | ModRM | Lock,
+	DstMem | SrcImm | ModRM | Lock,
+	DstMem | SrcImm | ModRM | Lock,
+	DstMem | SrcImm | ModRM | Lock,
+	DstMem | SrcImm | ModRM,
 	[Group1_82*8] =
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
-	ByteOp | DstMem | SrcImm | ModRM, ByteOp | DstMem | SrcImm | ModRM,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | Lock,
+	ByteOp | DstMem | SrcImm | ModRM,
 	[Group1_83*8] =
-	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
-	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
-	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
-	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
+	DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM,
 	[Group1A*8] =
 	DstMem | SrcNone | ModRM | Mov | Stack, 0, 0, 0, 0, 0, 0, 0,
 	[Group3_Byte*8] =
@@ -332,10 +350,10 @@ static u32 group_table[] = {
 	SrcMem16 | ModRM | Mov | Priv, SrcMem | ModRM | ByteOp | Priv,
 	[Group8*8] =
 	0, 0, 0, 0,
-	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
-	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM,
+	DstMem | SrcImmByte | ModRM, DstMem | SrcImmByte | ModRM | Lock,
+	DstMem | SrcImmByte | ModRM | Lock, DstMem | SrcImmByte | ModRM | Lock,
 	[Group9*8] =
-	0, ImplicitOps | ModRM, 0, 0, 0, 0, 0, 0,
+	0, ImplicitOps | ModRM | Lock, 0, 0, 0, 0, 0, 0,
 };
 
 static u32 group2_table[] = {
@@ -1580,8 +1598,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt)
 	u64 msr_data;
 
 	/* syscall is not available in real mode */
-	if (c->lock_prefix || ctxt->mode == X86EMUL_MODE_REAL
-	    || ctxt->mode == X86EMUL_MODE_VM86)
+	if (ctxt->mode == X86EMUL_MODE_REAL || ctxt->mode == X86EMUL_MODE_VM86)
 		return -1;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
@@ -1629,10 +1646,6 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 	struct kvm_segment cs, ss;
 	u64 msr_data;
 
-	/* inject #UD if LOCK prefix is used */
-	if (c->lock_prefix)
-		return -1;
-
 	/* inject #GP if in real mode */
 	if (ctxt->mode == X86EMUL_MODE_REAL) {
 		kvm_inject_gp(ctxt->vcpu, 0);
@@ -1694,10 +1707,6 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 	u64 msr_data;
 	int usermode;
 
-	/* inject #UD if LOCK prefix is used */
-	if (c->lock_prefix)
-		return -1;
-
 	/* inject #GP if in real mode or Virtual 8086 mode */
 	if (ctxt->mode == X86EMUL_MODE_REAL ||
 	    ctxt->mode == X86EMUL_MODE_VM86) {
@@ -1819,6 +1828,12 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
 	saved_eip = c->eip;
 
+	/* LOCK prefix is allowed only with some instructions */
+	if (c->lock_prefix && !(c->d & Lock)) {
+		kvm_queue_exception(ctxt->vcpu, UD_VECTOR);
+		goto done;
+	}
+
 	/* Privileged instruction can be executed only in CPL=0 */
 	if ((c->d & Priv) && kvm_x86_ops->get_cpl(ctxt->vcpu)) {
 		kvm_inject_gp(ctxt->vcpu, 0);
-- 
cgit v1.2.3


From 1d327eac3c9a8b170d68df44957d82bdbd263c53 Mon Sep 17 00:00:00 2001
From: Wei Yongjun <yjwei@cn.fujitsu.com>
Date: Thu, 11 Feb 2010 11:12:07 +0800
Subject: KVM: x86 emulator: code style cleanup

Just remove redundant semicolon.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index c2de9f03da84..dd1b93522379 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1016,7 +1016,7 @@ done_prefixes:
 	}
 
 	if (mode == X86EMUL_MODE_PROT64 && (c->d & No64)) {
-		kvm_report_emulation_failure(ctxt->vcpu, "invalid x86/64 instruction");;
+		kvm_report_emulation_failure(ctxt->vcpu, "invalid x86/64 instruction");
 		return -1;
 	}
 
-- 
cgit v1.2.3


From e424e1918345ab17d3beb068b8745ab1706d0e1b Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Thu, 11 Feb 2010 12:41:10 +0200
Subject: KVM: x86 emulator: disallow opcode 82 in 64-bit mode

Instructions with opcode 82 are not valid in 64 bit mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index dd1b93522379..c280c2352f7e 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -310,14 +310,14 @@ static u32 group_table[] = {
 	DstMem | SrcImm | ModRM | Lock,
 	DstMem | SrcImm | ModRM,
 	[Group1_82*8] =
-	ByteOp | DstMem | SrcImm | ModRM | Lock,
-	ByteOp | DstMem | SrcImm | ModRM | Lock,
-	ByteOp | DstMem | SrcImm | ModRM | Lock,
-	ByteOp | DstMem | SrcImm | ModRM | Lock,
-	ByteOp | DstMem | SrcImm | ModRM | Lock,
-	ByteOp | DstMem | SrcImm | ModRM | Lock,
-	ByteOp | DstMem | SrcImm | ModRM | Lock,
-	ByteOp | DstMem | SrcImm | ModRM,
+	ByteOp | DstMem | SrcImm | ModRM | No64 | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | No64 | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | No64 | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | No64 | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | No64 | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | No64 | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | No64 | Lock,
+	ByteOp | DstMem | SrcImm | ModRM | No64,
 	[Group1_83*8] =
 	DstMem | SrcImmByte | ModRM | Lock,
 	DstMem | SrcImmByte | ModRM | Lock,
-- 
cgit v1.2.3


From 8b9f44140bc4afd2698413cd9960c3912168ee91 Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Thu, 18 Feb 2010 12:14:59 +0200
Subject: KVM: x86 emulator: Forbid modifying CS segment register by mov
 instruction

Inject #UD if guest attempts to do so. This is in accordance to Intel
SDM.

Cc: stable@kernel.org (2.6.33, 2.6.32)
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index c280c2352f7e..2db760ff887c 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2126,6 +2126,12 @@ special_insn:
 		int err;
 
 		sel = c->src.val;
+
+		if (c->modrm_reg == VCPU_SREG_CS) {
+			kvm_queue_exception(ctxt->vcpu, UD_VECTOR);
+			goto done;
+		}
+
 		if (c->modrm_reg == VCPU_SREG_SS)
 			toggle_interruptibility(ctxt, X86_SHADOW_INT_MOV_SS);
 
-- 
cgit v1.2.3


From c697518a861e6c43b92b848895f9926580ee63c3 Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Thu, 18 Feb 2010 12:15:01 +0200
Subject: KVM: Fix segment descriptor loading

Add proper error and permission checking. This patch also change task
switching code to load segment selectors before segment descriptors, like
SDM requires, otherwise permission checking during segment descriptor
loading will be incorrect.

Cc: stable@kernel.org (2.6.33, 2.6.32)
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 30 ++++++++----------------------
 1 file changed, 8 insertions(+), 22 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2db760ff887c..a1a7b27adf41 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1309,7 +1309,7 @@ static int emulate_pop_sreg(struct x86_emulate_ctxt *ctxt,
 	if (rc != 0)
 		return rc;
 
-	rc = kvm_load_segment_descriptor(ctxt->vcpu, (u16)selector, 1, seg);
+	rc = kvm_load_segment_descriptor(ctxt->vcpu, (u16)selector, seg);
 	return rc;
 }
 
@@ -1491,7 +1491,7 @@ static int emulate_ret_far(struct x86_emulate_ctxt *ctxt,
 	rc = emulate_pop(ctxt, ops, &cs, c->op_bytes);
 	if (rc)
 		return rc;
-	rc = kvm_load_segment_descriptor(ctxt->vcpu, (u16)cs, 1, VCPU_SREG_CS);
+	rc = kvm_load_segment_descriptor(ctxt->vcpu, (u16)cs, VCPU_SREG_CS);
 	return rc;
 }
 
@@ -2122,12 +2122,11 @@ special_insn:
 		break;
 	case 0x8e: { /* mov seg, r/m16 */
 		uint16_t sel;
-		int type_bits;
-		int err;
 
 		sel = c->src.val;
 
-		if (c->modrm_reg == VCPU_SREG_CS) {
+		if (c->modrm_reg == VCPU_SREG_CS ||
+		    c->modrm_reg > VCPU_SREG_GS) {
 			kvm_queue_exception(ctxt->vcpu, UD_VECTOR);
 			goto done;
 		}
@@ -2135,18 +2134,7 @@ special_insn:
 		if (c->modrm_reg == VCPU_SREG_SS)
 			toggle_interruptibility(ctxt, X86_SHADOW_INT_MOV_SS);
 
-		if (c->modrm_reg <= 5) {
-			type_bits = (c->modrm_reg == 1) ? 9 : 1;
-			err = kvm_load_segment_descriptor(ctxt->vcpu, sel,
-							  type_bits, c->modrm_reg);
-		} else {
-			printk(KERN_INFO "Invalid segreg in modrm byte 0x%02x\n",
-					c->modrm);
-			goto cannot_emulate;
-		}
-
-		if (err < 0)
-			goto cannot_emulate;
+		rc = kvm_load_segment_descriptor(ctxt->vcpu, sel, c->modrm_reg);
 
 		c->dst.type = OP_NONE;  /* Disable writeback. */
 		break;
@@ -2320,11 +2308,9 @@ special_insn:
 	case 0xe9: /* jmp rel */
 		goto jmp;
 	case 0xea: /* jmp far */
-		if (kvm_load_segment_descriptor(ctxt->vcpu, c->src2.val, 9,
-					VCPU_SREG_CS) < 0) {
-			DPRINTF("jmp far: Failed to load CS descriptor\n");
-			goto cannot_emulate;
-		}
+		if (kvm_load_segment_descriptor(ctxt->vcpu, c->src2.val,
+						VCPU_SREG_CS))
+			goto done;
 
 		c->eip = c->src.val;
 		break;
-- 
cgit v1.2.3


From e54cfa97a9ca9a544a7257b89b530b505ae1b892 Mon Sep 17 00:00:00 2001
From: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Date: Thu, 18 Feb 2010 12:15:02 +0200
Subject: KVM: Fix emulate_sys[call, enter, exit]()'s fault handling

This patch fixes emulate_syscall(), emulate_sysenter() and
emulate_sysexit() to handle injected faults properly.

Even though original code injects faults in these functions,
we cannot handle these unless we use the different return
value from the UNHANDLEABLE case. So this patch use X86EMUL_*
codes instead of -1 and 0 and makes x86_emulate_insn() to
handle these propagated faults.

Be sure that, in x86_emulate_insn(), goto cannot_emulate and
goto done with rc equals X86EMUL_UNHANDLEABLE have same effect.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 arch/x86/kvm/emulate.c | 37 ++++++++++++++++++++-----------------
 1 file changed, 20 insertions(+), 17 deletions(-)

(limited to 'arch/x86/kvm/emulate.c')

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index a1a7b27adf41..4dade6ac0827 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1599,7 +1599,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt)
 
 	/* syscall is not available in real mode */
 	if (ctxt->mode == X86EMUL_MODE_REAL || ctxt->mode == X86EMUL_MODE_VM86)
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
 
@@ -1636,7 +1636,7 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt)
 		ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
 	}
 
-	return 0;
+	return X86EMUL_CONTINUE;
 }
 
 static int
@@ -1649,14 +1649,14 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 	/* inject #GP if in real mode */
 	if (ctxt->mode == X86EMUL_MODE_REAL) {
 		kvm_inject_gp(ctxt->vcpu, 0);
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 	}
 
 	/* XXX sysenter/sysexit have not been tested in 64bit mode.
 	* Therefore, we inject an #UD.
 	*/
 	if (ctxt->mode == X86EMUL_MODE_PROT64)
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
 
@@ -1665,13 +1665,13 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 	case X86EMUL_MODE_PROT32:
 		if ((msr_data & 0xfffc) == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		break;
 	case X86EMUL_MODE_PROT64:
 		if (msr_data == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		break;
 	}
@@ -1696,7 +1696,7 @@ emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 	kvm_x86_ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_ESP, &msr_data);
 	c->regs[VCPU_REGS_RSP] = msr_data;
 
-	return 0;
+	return X86EMUL_CONTINUE;
 }
 
 static int
@@ -1711,7 +1711,7 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 	if (ctxt->mode == X86EMUL_MODE_REAL ||
 	    ctxt->mode == X86EMUL_MODE_VM86) {
 		kvm_inject_gp(ctxt->vcpu, 0);
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 	}
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
@@ -1729,7 +1729,7 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 		cs.selector = (u16)(msr_data + 16);
 		if ((msr_data & 0xfffc) == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		ss.selector = (u16)(msr_data + 24);
 		break;
@@ -1737,7 +1737,7 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 		cs.selector = (u16)(msr_data + 32);
 		if (msr_data == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		ss.selector = cs.selector + 8;
 		cs.db = 0;
@@ -1753,7 +1753,7 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 	c->eip = ctxt->vcpu->arch.regs[VCPU_REGS_RDX];
 	c->regs[VCPU_REGS_RSP] = ctxt->vcpu->arch.regs[VCPU_REGS_RCX];
 
-	return 0;
+	return X86EMUL_CONTINUE;
 }
 
 static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt)
@@ -2476,8 +2476,9 @@ twobyte_insn:
 		}
 		break;
 	case 0x05: 		/* syscall */
-		if (emulate_syscall(ctxt) == -1)
-			goto cannot_emulate;
+		rc = emulate_syscall(ctxt);
+		if (rc != X86EMUL_CONTINUE)
+			goto done;
 		else
 			goto writeback;
 		break;
@@ -2548,14 +2549,16 @@ twobyte_insn:
 		c->dst.type = OP_NONE;
 		break;
 	case 0x34:		/* sysenter */
-		if (emulate_sysenter(ctxt) == -1)
-			goto cannot_emulate;
+		rc = emulate_sysenter(ctxt);
+		if (rc != X86EMUL_CONTINUE)
+			goto done;
 		else
 			goto writeback;
 		break;
 	case 0x35:		/* sysexit */
-		if (emulate_sysexit(ctxt) == -1)
-			goto cannot_emulate;
+		rc = emulate_sysexit(ctxt);
+		if (rc != X86EMUL_CONTINUE)
+			goto done;
 		else
 			goto writeback;
 		break;
-- 
cgit v1.2.3