NetKvm: 'm_VirtQueue' NULL pointer dereference

[wangyan0507]

Describe the bug
Open windows ‘verifier’ for Netkvm, I found a blue screen when starting the windows virtual machine.
The code as follows:

ParaNdis_PowerOn
    ->pContext->CXPath.Renew()
        ->CVirtQueue::Renew()
            ->status = virtio_find_queue()
                -> allocate memory failed, return error
            ->if (!NT_SUCCESS(status))
                ->m_VirtQueue = nullptr;  // Now, m_VirtQueue is NULL.
    ->ParaNdis_RestoreDeviceConfigurationAfterReset()
        ->ParaNdis_FinishInitialization()
            ->ParaNdis_ConfigureMSIXVectors()
                ->SetupMessageIndex()
                    ->m_pVirtQueue->SetMSIVector(vector)  // m_pVirtQueue NULL pointer dereference

[YanVugenfirer]

@wangyan0507 Can you describe the scenario that you are using to get the blue screen?

[wangyan0507]

@wangyan0507 Can you describe the scenario that you are using to get the blue screen?

I use qemu to start a windows virtual machine, open windows Driver Verifier for all drivers, and repeat boot and shutdown windows.
For Driver Verifier, I choose as follows:
'Create custom settings (for code developers)' and then select all form the full list.
I think the 'systematic low resources simulation' option may cause alloc memory failed, and caused this problem.
The full dump stack as follows:

It caused blue screen when booting the windows vm. We can find the NULL pointer dereference in the NetKvm code. It seems pretty obvious.

[wangyan0507]

@YanVugenfirer @ybendito I have updated the description, the NULL pointer dereference in this place:

[ybendito]

@wangyan0507 Do you have hibernation enabled? (powercfg /a)

[heywji]

Hi @wangyan0507, Did you encounter the BSOD stop code as "KMODE EXCEPTION NOT HANDLED"?

[wangyan0507]

Hi @wangyan0507, Did you encounter the BSOD stop code as "KMODE EXCEPTION NOT HANDLED"?

Yes, it is "SYSTEM_THREAD_EXECPTION_NOT_HANDLED (7e)" in the full dump file.

[wangyan0507]

@wangyan0507 Do you have hibernation enabled? (powercfg /a)

No, just enabled 'Fast Startup' .

[heywji]

Open a downstream Jira to track this issue: https://issues.redhat.com/browse/RHEL-68725

[YanVugenfirer]

No, just enabled 'Fast Startup' .

Fast startup uses hibernate

[wangyan0507]

No, just enabled 'Fast Startup' .

Fast startup uses hibernate

hibernation can cause this problem?

[YanVugenfirer]

Combination of driver verifier with low resource simulation and hibernation. On hibernation, the driver will reinitialize and re-allocate some of the internal data structures.

[ybendito]

@wangyan0507 Driver from #1206
NetKVM-Win2019x64.zip
Please close the issue if the problem is solved

[wangyan0507]

@wangyan0507 Driver from #1206 NetKVM-Win2019x64.zip Please close the issue if the problem is solved

I will test it.

[wangyan0507]

The problem is solved