From 30a759b61a9247378a9cb84fbe4e437ae66e0461 Mon Sep 17 00:00:00 2001 From: Roman Kagan Date: Mon, 26 Nov 2018 15:28:44 +0000 Subject: hw/hyperv: fix NULL dereference with pure-kvm SynIC MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When started in compat configuration of SynIC, e.g. qemu-system-x86_64 -machine pc-i440fx-2.10,accel=kvm \ -cpu host,-vmx,hv-relaxed,hv_spinlocks=0x1fff,hv-vpindex,hv-synic or explicitly qemu-system-x86_64 -enable-kvm -cpu host,hv-synic,x-hv-synic-kvm-only=on QEMU crashes in hyperv_synic_reset() trying to access the non-present qobject for SynIC. Add the missing check for NULL. Reported-by: Vitaly Kuznetsov Reported-by: Igor Mammedov Fixes: 9b4cf107b09d18ac30f46fd1c4de8585ccba030c Fixes: 4a93722f9c279184e95b1e1ad775c01deec05065 Signed-off-by: Roman Kagan Message-Id: <20181126152836.25379-1-rkagan@virtuozzo.com> Reviewed-by: Philippe Mathieu-Daudé Tested-by: Philippe Mathieu-Daudé Signed-off-by: Eduardo Habkost --- hw/hyperv/hyperv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'hw/hyperv') diff --git a/hw/hyperv/hyperv.c b/hw/hyperv/hyperv.c index a28e7249d8..8758635227 100644 --- a/hw/hyperv/hyperv.c +++ b/hw/hyperv/hyperv.c @@ -136,7 +136,11 @@ void hyperv_synic_add(CPUState *cs) void hyperv_synic_reset(CPUState *cs) { - device_reset(DEVICE(get_synic(cs))); + SynICState *synic = get_synic(cs); + + if (synic) { + device_reset(DEVICE(synic)); + } } static const TypeInfo synic_type_info = { -- cgit v1.2.3