CVE-2014-3633: qemu: blkiotune: Use correct definition when looking up disk

Live definition was used to look up the disk index while persistent one
was indexed leading to a crash in qemuDomainGetBlockIoTune. Use the
correct def and report a nice error.

Thanks: Peter Krempa
Closes: #762203

debian/patches/security/CVE-2014-3633-qemu-blkiotune-Use-correct-definition-.patch

+From: Peter Krempa <pkrempa@redhat.com>
+Date: Thu, 11 Sep 2014 16:35:53 +0200
+Subject: CVE-2014-3633: qemu: blkiotune: Use correct definition when looking
+ up disk
+
+Live definition was used to look up the disk index while persistent one
+was indexed leading to a crash in qemuDomainGetBlockIoTune. Use the
+correct def and report a nice error.
+
+Unfortunately it's accessible via read-only connection, though it can
+only crash libvirtd in the cases where the guest is hot-plugging disks
+without reflecting those changes to the persistent definition.  So
+avoiding hotplug, or doing hotplug where persistent is always modified
+alongside live definition, will avoid the out-of-bounds access.
+
+Introduced in: eca96694a7f992be633d48d5ca03cedc9bbc3c9aa (v0.9.8)
+Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1140724
+Reported-by: Luyao Huang <lhuang@redhat.com>
+Signed-off-by: Peter Krempa <pkrempa@redhat.com>
+---
+ src/qemu/qemu_driver.c | 8 ++++++--
+ 1 file changed, 6 insertions(+), 2 deletions(-)
+
+diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
+index 239a300..291f490 100644
+--- a/src/qemu/qemu_driver.c
++++ b/src/qemu/qemu_driver.c
+@@ -16141,9 +16141,13 @@ qemuDomainGetBlockIoTune(virDomainPtr dom,
+     }
+ 
+     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
+-        int idx = virDomainDiskIndexByName(vm->def, disk, true);
+-        if (idx < 0)
++        int idx = virDomainDiskIndexByName(persistentDef, disk, true);
++        if (idx < 0) {
++            virReportError(VIR_ERR_INVALID_ARG,
++                           _("disk '%s' was not found in the domain config"),
++                           disk);
+             goto endjob;
++        }
+         reply = persistentDef->disks[idx]->blkdeviotune;
+     }
+ 

debian/patches/series

@@ -13,3 +13,4 @@ Allow-xen-toolstack-to-find-it-s-binaries.patch
 Skip-vircgrouptest.patch
 debian/Use-sensible-editor-as-fallback.patch
 debian/Debianize-virtlockd.patch
+security/CVE-2014-3633-qemu-blkiotune-Use-correct-definition-.patch