Commit ef0e8fc7 authored by Eduardo Habkost's avatar Eduardo Habkost Committed by Michael S. Tsirkin
Browse files

iommu: Don't crash if machine is not PC_MACHINE 



Currently it's possible to crash QEMU using "-device *-iommu" and
"-machine none":

  $ qemu-system-x86_64 -machine none -device amd-iommu
  qemu/hw/i386/amd_iommu.c:1140:amdvi_realize: Object 0x55627dafbc90 is not an instance of type generic-pc-machine
  Aborted (core dumped)
  $ qemu-system-x86_64 -machine none -device intel-iommu
  qemu/hw/i386/intel_iommu.c:2972:vtd_realize: Object 0x56292ec0bc90 is not an instance of type generic-pc-machine
  Aborted (core dumped)

Fix amd-iommu and intel-iommu to ensure the current machine is really a
TYPE_PC_MACHINE instance at their realize methods.

Resulting error messages:

  $ qemu-system-x86_64 -machine none -device amd-iommu
  qemu-system-x86_64: -device amd-iommu: Machine-type 'none' not supported by amd-iommu
  $ qemu-system-x86_64 -machine none -device intel-iommu
  qemu-system-x86_64: -device intel-iommu: Machine-type 'none' not supported by intel-iommu

Signed-off-by: default avatarEduardo Habkost <ehabkost@redhat.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 465238d9

hw/i386/amd_iommu.c

+14 −1
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ 
 */

#include "qemu/osdep.h"

#include "hw/i386/amd_iommu.h"

#include "qapi/error.h"

#include "qemu/error-report.h"

#include "trace.h"
@@ -1137,7 +1138,19 @@ static void amdvi_realize(DeviceState *dev, Error **err) 
    int ret = 0;

    AMDVIState *s = AMD_IOMMU_DEVICE(dev);

    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);

    PCIBus *bus = PC_MACHINE(qdev_get_machine())->bus;

    MachineState *ms = MACHINE(qdev_get_machine());

    MachineClass *mc = MACHINE_GET_CLASS(ms);

    PCMachineState *pcms =

        PC_MACHINE(object_dynamic_cast(OBJECT(ms), TYPE_PC_MACHINE));

    PCIBus *bus;



    if (!pcms) {

        error_setg(err, "Machine-type '%s' not supported by amd-iommu",

                   mc->name);

        return;

    }



    bus = pcms->bus;

    s->iotlb = g_hash_table_new_full(amdvi_uint64_hash,

                                     amdvi_uint64_equal, g_free, g_free);

hw/i386/intel_iommu.c

+12 −2
Original line number Diff line number Diff line
@@ -2969,11 +2969,21 @@ static bool vtd_decide_config(IntelIOMMUState *s, Error **errp) 


static void vtd_realize(DeviceState *dev, Error **errp)

{

    PCMachineState *pcms = PC_MACHINE(qdev_get_machine());

    PCIBus *bus = pcms->bus;

    MachineState *ms = MACHINE(qdev_get_machine());

    MachineClass *mc = MACHINE_GET_CLASS(ms);

    PCMachineState *pcms =

        PC_MACHINE(object_dynamic_cast(OBJECT(ms), TYPE_PC_MACHINE));

    PCIBus *bus;

    IntelIOMMUState *s = INTEL_IOMMU_DEVICE(dev);

    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);



    if (!pcms) {

        error_setg(errp, "Machine-type '%s' not supported by intel-iommu",

                   mc->name);

        return;

    }



    bus = pcms->bus;

    VTD_DPRINTF(GENERAL, "");

    x86_iommu->type = TYPE_INTEL;