From abfcb113bd1200dc91e8d6e3bcbd2084d458f554 Mon Sep 17 00:00:00 2001

Message-Id: <abfcb113bd1200dc91e8d6e3bcbd2084d458f554@dist-git>

From: Jiri Denemark <jdenemar@redhat.com>

Date: Fri, 12 Apr 2019 21:21:05 +0200

Subject: [PATCH] qemu: Don't cache microcode version

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My earlier commit be46f61326 was incomplete. It removed caching of

microcode version in the CPU driver, which means the capabilities XML

will see the correct microcode version. But it is also cached in the

QEMU capabilities cache where it is used to detect whether we need to

reprobe QEMU. By missing the second place, the original commit

be46f61326 made the situation even worse since libvirt would report

correct microcode version while still using the old host CPU model

(visible in domain capabilities XML).

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

Reviewed-by: Ján Tomko <jtomko@redhat.com>

(cherry picked from commit 673c62a3b7855a0685d8f116e227c402720b9ee9)

CVE-2018-12126, CVE-2018-12127, CVE-2018-12130

Conflicts:

	src/qemu/qemu_capabilities.c

            - virQEMUCapsCacheLookupByArch refactoring (commits

              7948ad4129a and 1a3de67001c) are missing

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

---

 src/qemu/qemu_capabilities.c | 12 ++++++++----

 src/qemu/qemu_capabilities.h |  3 +--

 src/qemu/qemu_driver.c       |  9 +--------

 tests/testutilsqemu.c        |  2 +-

 4 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c

index 4f2051a2bb..96aa1b15e4 100644

--- a/src/qemu/qemu_capabilities.c

+++ b/src/qemu/qemu_capabilities.c

@@ -4625,7 +4625,7 @@ virQEMUCapsNewData(const char *binary,

                                            priv->libDir,

                                            priv->runUid,

                                            priv->runGid,

-                                           priv->microcodeVersion,

+                                           virHostCPUGetMicrocodeVersion(),

                                            priv->kernelVersion);

 }

@@ -4708,8 +4708,7 @@ virFileCachePtr

 virQEMUCapsCacheNew(const char *libDir,

                     const char *cacheDir,

                     uid_t runUid,

-                    gid_t runGid,

-                    unsigned int microcodeVersion)

+                    gid_t runGid)

 {

     char *capsCacheDir = NULL;

     virFileCachePtr cache = NULL;

@@ -4733,7 +4732,6 @@ virQEMUCapsCacheNew(const char *libDir,

     priv->runUid = runUid;

     priv->runGid = runGid;

-    priv->microcodeVersion = microcodeVersion;

     if (uname(&uts) == 0 &&

         virAsprintf(&priv->kernelVersion, "%s %s", uts.release, uts.version) < 0)

@@ -4754,8 +4752,11 @@ virQEMUCapsPtr

 virQEMUCapsCacheLookup(virFileCachePtr cache,

                        const char *binary)

 {

+    virQEMUCapsCachePrivPtr priv = virFileCacheGetPriv(cache);

     virQEMUCapsPtr ret = NULL;

+    priv->microcodeVersion = virHostCPUGetMicrocodeVersion();

+

     ret = virFileCacheLookup(cache, binary);

     VIR_DEBUG("Returning caps %p for %s", ret, binary);

@@ -4801,10 +4802,13 @@ virQEMUCapsPtr

 virQEMUCapsCacheLookupByArch(virFileCachePtr cache,

                              virArch arch)

 {

+    virQEMUCapsCachePrivPtr priv = virFileCacheGetPriv(cache);

     virQEMUCapsPtr ret = NULL;

     virArch target;

     struct virQEMUCapsSearchData data = { .arch = arch };

+    priv->microcodeVersion = virHostCPUGetMicrocodeVersion();

+

     ret = virFileCacheLookupByFunc(cache, virQEMUCapsCompareArch, &data);

     if (!ret) {

         /* If the first attempt at finding capabilities has failed, try

diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h

index 9e8ad5f5c3..7a91b7da62 100644

--- a/src/qemu/qemu_capabilities.h

+++ b/src/qemu/qemu_capabilities.h

@@ -572,8 +572,7 @@ void virQEMUCapsFilterByMachineType(virQEMUCapsPtr qemuCaps,

 virFileCachePtr virQEMUCapsCacheNew(const char *libDir,

                                     const char *cacheDir,

                                     uid_t uid,

-                                    gid_t gid,

-                                    unsigned int microcodeVersion);

+                                    gid_t gid);

 virQEMUCapsPtr virQEMUCapsCacheLookup(virFileCachePtr cache,

                                       const char *binary);

 virQEMUCapsPtr virQEMUCapsCacheLookupCopy(virFileCachePtr cache,

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c

index 295613ba3c..21d836a540 100644

--- a/src/qemu/qemu_driver.c

+++ b/src/qemu/qemu_driver.c

@@ -592,8 +592,6 @@ qemuStateInitialize(bool privileged,

     char *hugepagePath = NULL;

     char *memoryBackingPath = NULL;

     size_t i;

-    virCPUDefPtr hostCPU = NULL;

-    unsigned int microcodeVersion = 0;

     if (VIR_ALLOC(qemu_driver) < 0)

         return -1;

@@ -813,15 +811,10 @@ qemuStateInitialize(bool privileged,

         run_gid = cfg->group;

     }

-    if ((hostCPU = virCPUProbeHost(virArchFromHost())))

-        microcodeVersion = hostCPU->microcodeVersion;

-    virCPUDefFree(hostCPU);

-

     qemu_driver->qemuCapsCache = virQEMUCapsCacheNew(cfg->libDir,

                                                      cfg->cacheDir,

                                                      run_uid,

-                                                     run_gid,

-                                                     microcodeVersion);

+                                                     run_gid);

     if (!qemu_driver->qemuCapsCache)

         goto error;

diff --git a/tests/testutilsqemu.c b/tests/testutilsqemu.c

index dc7e90b952..3e0b753549 100644

--- a/tests/testutilsqemu.c

+++ b/tests/testutilsqemu.c

@@ -617,7 +617,7 @@ int qemuTestDriverInit(virQEMUDriver *driver)

     /* Using /dev/null for libDir and cacheDir automatically produces errors

      * upon attempt to use any of them */

-    driver->qemuCapsCache = virQEMUCapsCacheNew("/dev/null", "/dev/null", 0, 0, 0);

+    driver->qemuCapsCache = virQEMUCapsCacheNew("/dev/null", "/dev/null", 0, 0);

     if (!driver->qemuCapsCache)

         goto error;

-- 

2.21.0