|
 |
b136801 |
From: Nadav Amit <namit@cs.technion.ac.il>
|
|
|
b136801 |
Date: Fri, 24 Oct 2014 17:07:23 +0200
|
|
|
b136801 |
Subject: [PATCH] KVM: x86: PREFETCH and HINT_NOP should have SrcMem flag
|
|
|
b136801 |
|
|
|
b136801 |
The decode phase of the x86 emulator assumes that every instruction with the
|
|
|
b136801 |
ModRM flag, and which can be used with RIP-relative addressing, has either
|
|
|
b136801 |
SrcMem or DstMem. This is not the case for several instructions - prefetch,
|
|
|
b136801 |
hint-nop and clflush.
|
|
|
b136801 |
|
|
|
b136801 |
Adding SrcMem|NoAccess for prefetch and hint-nop and SrcMem for clflush.
|
|
|
b136801 |
|
|
|
b136801 |
This fixes CVE-2014-8480.
|
|
|
b136801 |
|
|
|
b136801 |
Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5
|
|
|
b136801 |
Cc: stable@vger.kernel.org
|
|
|
b136801 |
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
|
|
|
b136801 |
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
|
b136801 |
---
|
|
|
b136801 |
arch/x86/kvm/emulate.c | 7 ++++---
|
|
|
b136801 |
1 file changed, 4 insertions(+), 3 deletions(-)
|
|
|
b136801 |
|
|
|
b136801 |
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
|
|
|
b136801 |
index d1a19289d11a..48daa1a097af 100644
|
|
|
b136801 |
--- a/arch/x86/kvm/emulate.c
|
|
|
b136801 |
+++ b/arch/x86/kvm/emulate.c
|
|
|
b136801 |
@@ -3797,7 +3797,7 @@ static const struct opcode group11[] = {
|
|
|
b136801 |
};
|
|
|
b136801 |
|
|
|
b136801 |
static const struct gprefix pfx_0f_ae_7 = {
|
|
|
b136801 |
- I(0, em_clflush), N, N, N,
|
|
|
b136801 |
+ I(SrcMem | ByteOp, em_clflush), N, N, N,
|
|
|
b136801 |
};
|
|
|
b136801 |
|
|
|
b136801 |
static const struct group_dual group15 = { {
|
|
|
b136801 |
@@ -4010,10 +4010,11 @@ static const struct opcode twobyte_table[256] = {
|
|
|
b136801 |
N, I(ImplicitOps | EmulateOnUD, em_syscall),
|
|
|
b136801 |
II(ImplicitOps | Priv, em_clts, clts), N,
|
|
|
b136801 |
DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N,
|
|
|
b136801 |
- N, D(ImplicitOps | ModRM), N, N,
|
|
|
b136801 |
+ N, D(ImplicitOps | ModRM | SrcMem | NoAccess), N, N,
|
|
|
b136801 |
/* 0x10 - 0x1F */
|
|
|
b136801 |
N, N, N, N, N, N, N, N,
|
|
|
b136801 |
- D(ImplicitOps | ModRM), N, N, N, N, N, N, D(ImplicitOps | ModRM),
|
|
|
b136801 |
+ D(ImplicitOps | ModRM | SrcMem | NoAccess),
|
|
|
b136801 |
+ N, N, N, N, N, N, D(ImplicitOps | ModRM | SrcMem | NoAccess),
|
|
|
b136801 |
/* 0x20 - 0x2F */
|
|
|
b136801 |
DIP(ModRM | DstMem | Priv | Op3264 | NoMod, cr_read, check_cr_read),
|
|
|
b136801 |
DIP(ModRM | DstMem | Priv | Op3264 | NoMod, dr_read, check_dr_read),
|
|
|
b136801 |
--
|
|
|
b136801 |
1.9.3
|
|
|
b136801 |
|