[PATCH 0/1] MR3035: mmdevapi: Fix "use-before-init" in set_driver_prop_value.

[Torge Matthies (＠tmatthies)]

Signed-off-by: Torge Matthies

[PATCH 1/1] mmdevapi: Fix "use-before-init" in set_driver_prop_value.

[Torge Matthies]

From: Torge Matthies

Signed-off-by: Torge Matthies 
---
 dlls/mmdevapi/devenum.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/dlls/mmdevapi/devenum.c b/dlls/mmdevapi/devenum.c
index 2b7833edd08..8d6f00b0acb 100644
--- a/dlls/mmdevapi/devenum.c
+++ b/dlls/mmdevapi/devenum.c
@@ -244,6 +244,8 @@ static HRESULT set_driver_prop_value(GUID *id, const EDataFlow flow, const PROPE
     if (!drvs.pGetPropValue)
         return E_NOTIMPL;

+    PropVariantInit(&pv);
+
     hr = drvs.pGetPropValue(id, prop, &pv);

if (SUCCEEDED(hr))

[Huw Davies (＠huw)]

What's the route for this to happen?  Is `drv.pGetPropValue()` succeeding without updating `pv`?  If so, with which driver?

[Torge Matthies (＠tmatthies)]

On Mon Jun 12 07:16:53 2023 +0000, Huw Davies wrote:
> What's the route for this to happen?  Is `drv.pGetPropValue()`
> succeeding without updating `pv`?  If so, with which driver?

I have not looked into that yet, I just discovered this problem because Battle.net refused to start with my latest Wine builds, and it was crashing in the PropVariantClear. I am however getting this in the log:

```
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
0150:fixme:mmdevapi:MMDevice_SetPropValue Unhandled type 0
```

(driver should be winepulse.drv with pipewire-pulse as server)

[Huw Davies (＠huw)]

Try !3045 (in particular the second commit).

[Torge Matthies (＠tmatthies)]

On Mon Jun 12 20:13:11 2023 +0000, Huw Davies wrote:
> Try !3045 (in particular the second commit).

That MR fixes the problem too, I will close this one.

[PATCH 0/1] MR3035: mmdevapi: Fix "use-before-init" in set_driver_prop_value. - closed

[Torge Matthies (＠tmatthies)]

This merge request was closed by Torge Matthies.

[Davide Beatrici (＠davidebeatrici)]

Ouch, sorry for causing the regression. Was it always reproducible?