Re: [libvirt] [PATCH 1/2] daemon: Fix segfault by reloading daemon right after start

Libvirt could crash with segfault if user issue "service reload" right after "service start". One possible way to crash libvirt is to run reload during initialization of QEMU driver. It could happen when qemu driver will initialize qemu_driver_lock but don't have a time to set it's "config" and the SIGHUP arrives. The reload handler tries to get qemu_drv->config during "virStorageAutostart" and dereference it which ends with segfault. Let's ignore all reload requests until all drivers are initialized. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1179981 Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com&gt; --- daemon/libvirtd.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/daemon/libvirtd.c b/daemon/libvirtd.c index 86accaa..835e7dc 100644 --- a/daemon/libvirtd.c +++ b/daemon/libvirtd.c @@ -785,6 +785,11 @@ static void daemonReloadHandler(virNetServerPtr srv ATTRIBUTE_UNUSED, siginfo_t *sig ATTRIBUTE_UNUSED, void *opaque ATTRIBUTE_UNUSED) { + if (!driversInitialized) { + VIR_WARN("Drivers are not initialized, reload ignored"); + return; + } + VIR_INFO("Reloading configuration on SIGHUP"); virHookCall(VIR_HOOK_DRIVER_DAEMON, "-", VIR_HOOK_DAEMON_OP_RELOAD, SIGHUP, "SIGHUP", NULL, NULL);