[libvirt] [PATCH] qemu: only request sound cgroup ACL when required

When a SPICE or VNC graphics controller is present, and sound is piggybacked over a channel to the graphics device rather than directly accessing host hardware, then there is no need to grant host hardware access to that qemu process. * src/qemu/qemu_cgroup.c (qemuSetupCgroup): Prevent sound with spice, and with vnc when vnc_allow_host_audio is 0. Reported by Daniel Berrange. --- Daniel noticed this while reviewing the audit code - the audit proved that we were allowing more resources than necessary. src/qemu/qemu_cgroup.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c index b39b5e1..e71d3fa 100644 --- a/src/qemu/qemu_cgroup.c +++ b/src/qemu/qemu_cgroup.c @@ -241,7 +241,11 @@ int qemuSetupCgroup(struct qemud_driver *driver, goto cleanup; } - if (vm->def->nsounds) { + if (vm->def->nsounds && + (!vm->def->ngraphics || + ((vm->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_VNC && + driver->vncAllowHostAudio) || + (vm->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_SDL)))) { rc = virCgroupAllowDeviceMajor(cgroup, 'c', DEVICE_SND_MAJOR); qemuDomainCgroupAudit(vm, cgroup, "allow", "major", "sound", rc == 0); -- 1.7.4