On 09/17/2014 10:25 AM, Peter Krempa wrote: > 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. > Mitigation - a read-only connection 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@xxxxxxxxxx> > Signed-off-by: Peter Krempa <pkrempa@xxxxxxxxxx> > --- > src/qemu/qemu_driver.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) ACK. I can write up the libvirt security notice; we'll eventually need this backported to all the affected maint branches. I'll coordinate the backport effort with you on IRC. > > diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c > index a5a49ac..209c40e 100644 > --- a/src/qemu/qemu_driver.c > +++ b/src/qemu/qemu_driver.c > @@ -16317,9 +16317,13 @@ 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; > } > -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
Attachment:
signature.asc
Description: OpenPGP digital signature
-- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list