libvirt: Address Medium CVE-2024-2496 (#8567)

Author: aditjha-msft

SPECS/libvirt/CVE-2024-2496.patch

@@ -0,0 +1,88 @@
+From 2ca94317ac642a70921947150ced8acc674ccdc8 Mon Sep 17 00:00:00 2001
+From: Dmitry Frolov <frolov@swemel.ru>
+Date: Tue, 12 Sep 2023 15:56:47 +0300
+Subject: [PATCH] interface: fix udev_device_get_sysattr_value return value
+ check
+
+Reviewing the code I found that return value of function
+udev_device_get_sysattr_value() is dereferenced without a check.
+udev_device_get_sysattr_value() may return NULL by number of reasons.
+
+v2: VIR_DEBUG added, replaced STREQ(NULLSTR()) with STREQ_NULLABLE()
+v3: More checks added, to skip earlier. More verbose VIR_DEBUG.
+
+Signed-off-by: Dmitry Frolov <frolov@swemel.ru>
+Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
+---
+ src/interface/interface_backend_udev.c | 26 +++++++++++++++++++-------
+ 1 file changed, 19 insertions(+), 7 deletions(-)
+
+diff --git a/src/interface/interface_backend_udev.c b/src/interface/interface_backend_udev.c
+index a0485ddd21..fb6799ed94 100644
+--- a/src/interface/interface_backend_udev.c
++++ b/src/interface/interface_backend_udev.c
+@@ -23,6 +23,7 @@
+ #include <dirent.h>
+ #include <libudev.h>
+ 
++#include "virlog.h"
+ #include "virerror.h"
+ #include "virfile.h"
+ #include "datatypes.h"
+@@ -40,6 +41,8 @@
+ 
+ #define VIR_FROM_THIS VIR_FROM_INTERFACE
+ 
++VIR_LOG_INIT("interface.interface_backend_udev");
++
+ struct udev_iface_driver {
+     struct udev *udev;
+     /* pid file FD, ensures two copies of the driver can't use the same root */
+@@ -354,11 +357,20 @@ udevConnectListAllInterfaces(virConnectPtr conn,
+         const char *macaddr;
+         g_autoptr(virInterfaceDef) def = NULL;
+ 
+-        path = udev_list_entry_get_name(dev_entry);
+-        dev = udev_device_new_from_syspath(udev, path);
+-        name = udev_device_get_sysname(dev);
++        if (!(path = udev_list_entry_get_name(dev_entry))) {
++            VIR_DEBUG("Skipping interface, path == NULL");
++            continue;
++        }
++        if (!(dev = udev_device_new_from_syspath(udev, path))) {
++            VIR_DEBUG("Skipping interface '%s', dev == NULL", path);
++            continue;
++        }
++        if (!(name = udev_device_get_sysname(dev))) {
++            VIR_DEBUG("Skipping interface '%s', name == NULL", path);
++            continue;
++        }
+         macaddr = udev_device_get_sysattr_value(dev, "address");
+-        status = STREQ(udev_device_get_sysattr_value(dev, "operstate"), "up");
++        status = STREQ_NULLABLE(udev_device_get_sysattr_value(dev, "operstate"), "up");
+ 
+         def = udevGetMinimalDefForDevice(dev);
+         if (!virConnectListAllInterfacesCheckACL(conn, def)) {
+@@ -964,9 +976,9 @@ udevGetIfaceDef(struct udev *udev, const char *name)
+ 
+     /* MTU */
+     mtu_str = udev_device_get_sysattr_value(dev, "mtu");
+-    if (virStrToLong_ui(mtu_str, NULL, 10, &mtu) < 0) {
++    if (!mtu_str || virStrToLong_ui(mtu_str, NULL, 10, &mtu) < 0) {
+         virReportError(VIR_ERR_INTERNAL_ERROR,
+-                _("Could not parse MTU value '%s'"), mtu_str);
++                _("Could not parse MTU value '%s'"), NULLSTR(mtu_str));
+         goto error;
+     }
+     ifacedef->mtu = mtu;
+@@ -1089,7 +1101,7 @@ udevInterfaceIsActive(virInterfacePtr ifinfo)
+        goto cleanup;
+ 
+     /* Check if it's active or not */
+-    status = STREQ(udev_device_get_sysattr_value(dev, "operstate"), "up");
++    status = STREQ_NULLABLE(udev_device_get_sysattr_value(dev, "operstate"), "up");
+ 
+     udev_device_unref(dev);
+ 
+-- 
+GitLab

SPECS/libvirt/libvirt.spec

@@ -9,7 +9,7 @@
 Summary:        Virtualization API library that supports KVM, QEMU, Xen, ESX etc
 Name:           libvirt
 Version:        7.10.0
-Release:        7%{?dist}
+Release:        8%{?dist}
 License:        LGPLv2+
 Vendor:         Microsoft Corporation
 Distribution:   Mariner
@@ -19,6 +19,7 @@ Source0:        https://libvirt.org/sources/%{name}-%{version}.tar.xz
 # CVE-2023-2700 is fixed by https://gitlab.com/libvirt/libvirt/-/commit/6425a311b8ad19d6f9c0b315bf1d722551ea3585
 Patch1:         CVE-2023-2700.patch
 Patch2:         CVE-2024-1441.patch
+Patch3:         CVE-2024-2496.patch
 
 BuildRequires:  audit-libs-devel
 BuildRequires:  augeas
@@ -1056,6 +1057,9 @@ exit 0
 %{_libdir}/libnss_libvirt_guest.so.2
 
 %changelog
+* Tue Mar 26 2024 Adit Jha <aditjha@microsoft.com> - 7.10.0-8
+- Introduce patch to address CVE-2024-2496
+
 * Tue Mar 19 2024 Muhammad Falak <mwani@microsoft.com> - 7.10.0-7
 - Introduce patch to address CVE-2024-1441