Re: [libvirt] [PATCH] qemu:json: Fix daemon crash on handling domain shutdown event

On Tue, May 30, 2017 at 10:41:17 +0200, Erik Skultety wrote: > commit a8eba5036 added further checking of the guest shutdown cause, but > this enhancement is available since qemu 2.10, causing a crash because > of a NULL pointer dereference on older qemus. > > Thread 1 "libvirtd" received signal SIGSEGV, Segmentation fault. > 0x00007ffff72441af in virJSONValueObjectGet (object=0x0, > key=0x7fffd5ef11bf "guest") > at util/virjson.c:769 > 769 if (object->type != VIR_JSON_TYPE_OBJECT) > (gdb) bt > 0 in virJSONValueObjectGet > 1 in virJSONValueObjectGetBoolean > 2 in qemuMonitorJSONHandleShutdown > 3 in qemuMonitorJSONIOProcessEvent > 4 in qemuMonitorJSONIOProcessLine > 5 in qemuMonitorJSONIOProcess > 6 in qemuMonitorIOProcess I think you can truncate is somewhere here. > 7 in qemuMonitorIO > 8 in virEventPollDispatchHandles > 9 in virEventPollRunOnce > 10 in virEventRunDefaultImpl > 11 in virNetDaemonRun > 12 in main > > Signed-off-by: Erik Skultety <eskultet(a)redhat.com&gt; > --- > src/qemu/qemu_monitor_json.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c > index 757595dd7..f208dd05a 100644 > --- a/src/qemu/qemu_monitor_json.c > +++ b/src/qemu/qemu_monitor_json.c > @@ -528,7 +528,7 @@ static void qemuMonitorJSONHandleShutdown(qemuMonitorPtr mon, virJSONValuePtr da > bool guest = false; > virTristateBool guest_initiated = VIR_TRISTATE_BOOL_ABSENT; > > - if (virJSONValueObjectGetBoolean(data, "guest", &guest) == 0) > + if (data && virJSONValueObjectGetBoolean(data, "guest", &guest) == 0) > guest_initiated = guest ? VIR_TRISTATE_BOOL_YES : VIR_TRISTATE_BOOL_NO; > > qemuMonitorEmitShutdown(mon, guest_initiated); ACK, safe for freeze