Is there a reference for which registry keys fill (or are supposed to fill) which members of DeviceNode? I ask because I wind up finding all of the combinations that lead to zeros and have a tough time figuring out which registry values are needed to make them not be zero.
We have a lot of unchecked string functions on the DeviceNode fields in io/pnpmgr.c, by the way. I think i've stumbled on four such places so far, but I suspect that the whole thing should be hardened together.
In any case it would be nice if someone could post a cheat sheet about how to create a new device entry the right way, or write the code that fills the DeviceNode in a more obvious way, so that it's easy to find and see what fills what.
art yerkes wrote:
Is there a reference for which registry keys fill (or are supposed to fill) which members of DeviceNode? I ask because I wind up finding all of the combinations that lead to zeros and have a tough time figuring out which registry values are needed to make them not be zero.
- Only ServiceName is read from the registry and stored in the device node. - The rest is queried from the PDO created by bus driver (and possibly filtered by higher level drivers). - Some values are stored in registry and retrieved using IoGetDeviceProperty.
We have a lot of unchecked string functions on the DeviceNode fields in io/pnpmgr.c, by the way. I think i've stumbled on four such places so far, but I suspect that the whole thing should be hardened together.
Can you be more specific about this? Which strings? Which places?
In any case it would be nice if someone could post a cheat sheet about how to create a new device entry the right way,
It pretty much depends on the type of driver and the driver itself...
or write the code that fills the DeviceNode in a more obvious way, so that it's easy to find and see what fills what.
That's really hard. The current code (starting from IopInvalidateDeviceRelations) does several passes over the device tree and in each pass fills one part of the DEVICE_NODE. I can't really think about some clearer way...
Regards, Filip
We have a lot of unchecked string functions on the DeviceNode fields in io/pnpmgr.c, by the way. I think i've stumbled on four such places so far, but I suspect that the whole thing should be hardened together.
Can you be more specific about this? Which strings? Which places?
I'm wrong that there are a lot, these are the ones I've been bitten by. I think they're the only cases in which a wcscat/wcscpy is called on a possibly empty string.
line 171, DeviceNode->InstancePath.Buffer can be null. line 1059, DeviceNode->InstancePath.Buffer can be null.
-
art yerkes -
Filip Navara