Package: qemu-system-x86
Severity: grave
Tags: security

These are not upstreamed due to the embargo period, but I'm attaching
the 3.1 patches from Ubuntu 19.04.

Cheers,
        Moritz
>From a57fa50701c6a0fbe5ac7dbcc314c3c970bff899 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonz...@redhat.com>
Date: Fri, 1 Mar 2019 21:40:52 +0100
Subject: [qemu PATCH] target/i386: define md-clear bit

md-clear is a new CPUID bit which is set when microcode provides the
mechanism to invoke a flush of various exploitable CPU buffers by invoking
the VERW instruction.  Add the new feature, and pass it down to
Hypervisor.framework guests.

Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>

[Backported to qemu 3.1 - sbeattie]

---
        The last hunk is only needed for OS X, but anyway this is going
        to be the patch that will be committed upstream.

CVE-2018-12126, CVE-2018-12127, CVE-2018-12130, CVE-2019-11091

 target/i386/cpu.c           | 2 +-
 target/i386/cpu.h           | 1 +
 target/i386/hvf/x86_cpuid.c | 3 ++-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index d990070c59..16da90562c 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1075,7 +1075,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = 
{
         .feat_names = {
             NULL, NULL, "avx512-4vnniw", "avx512-4fmaps",
             NULL, NULL, NULL, NULL,
-            NULL, NULL, NULL, NULL,
+            NULL, NULL, "md-clear", NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, "pconfig", NULL,
             NULL, NULL, NULL, NULL,
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 26412f15eb..cbfab1a421 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -692,6 +692,7 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS];
 
 #define CPUID_7_0_EDX_AVX512_4VNNIW (1U << 2) /* AVX512 Neural Network 
Instructions */
 #define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply Accumulation 
Single Precision */
+#define CPUID_7_0_EDX_MD_CLEAR      (1U << 10) /* Microarchitectural Data 
Clear */
 #define CPUID_7_0_EDX_PCONFIG (1U << 18)       /* Platform Configuration */
 #define CPUID_7_0_EDX_SPEC_CTRL     (1U << 26) /* Speculation Control */
 #define CPUID_7_0_EDX_ARCH_CAPABILITIES (1U << 29)  /*Arch Capabilities*/
diff --git a/target/i386/hvf/x86_cpuid.c b/target/i386/hvf/x86_cpuid.c
index 9874a46e92..f76ba50424 100644
--- a/target/i386/hvf/x86_cpuid.c
+++ b/target/i386/hvf/x86_cpuid.c
@@ -103,7 +103,8 @@ uint32_t hvf_get_supported_cpuid(uint32_t func, uint32_t 
idx,
             }
 
             ecx &= CPUID_7_0_ECX_AVX512BMI | CPUID_7_0_ECX_AVX512_VPOPCNTDQ;
-            edx &= CPUID_7_0_EDX_AVX512_4VNNIW | CPUID_7_0_EDX_AVX512_4FMAPS;
+            edx &= CPUID_7_0_EDX_AVX512_4VNNIW | CPUID_7_0_EDX_AVX512_4FMAPS | 
\
+                   CPUID_7_0_EDX_MD_CLEAR;
         } else {
             ebx = 0;
             ecx = 0;
-- 
2.20.1

From: Paolo Bonzini <pbonz...@redhat.com>
Subject: [PATCH] target/i386: add MDS-NO feature

Microarchitectural Data Sampling is a hardware vulnerability which allows
unprivileged speculative access to data which is available in various CPU
internal buffers.

Some Intel processors use the ARCH_CAP_MDS_NO bit in the IA32_ARCH_CAPABILITIES
MSR to report that they are not vulnerable, make it available to guests.

Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
--
CVE-2018-12126, CVE-2018-12127, CVE-2018-12130, CVE-2019-11091

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 722c5514d4..558347e6c3 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1184,7 +1184,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = 
{
         .type = MSR_FEATURE_WORD,
         .feat_names = {
             "rdctl-no", "ibrs-all", "rsba", "skip-l1dfl-vmentry",
-            "ssb-no", NULL, NULL, NULL,
+            "ssb-no", "mds-no", NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,

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