[libvirt] [PATCH] qemu: Log error if domain uses security driver which is not loaded

[Erik Skultety]

When starting a domain, if we find out domain requests security drivers
we do not have loaded, we fail. However we don't check for this during
reconnect, so any operation relying on security driver functionality would fail.
If someone e.g. starts a domain with selinux driver loaded, then they turn off
the security driver in config, restart the daemon and call dump/save/..,
QEMU returns an error.
As we shouldn't kill the domain, we should at least log an error to let the
user know that domain reconnect wasn't completely clean.

https://bugzilla.redhat.com/show_bug.cgi?id=1183893
---
 src/qemu/qemu_process.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 56719eb..8da79e5 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -3747,6 +3747,12 @@ qemuProcessReconnect(void *opaque)
         if ((qemuDomainAssignAddresses(obj->def, priv->qemuCaps, obj)) < 0)
             goto error;
 
+    /* if domain requests security driver we haven't loaded, report error, but
+     * do not kill the domain
+     */
+    ignore_value(virSecurityManagerCheckAllLabel(driver->securityManager,
+                                                 obj->def));
+
     if (virSecurityManagerReserveLabel(driver->securityManager, obj->def, obj->pid) < 0)
         goto error;
 
-- 
1.9.3