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dato0011dato0011 Member Posts: 11
edited April 2020 in NTFSD

I'm trying to intercept calls to FindFirstFile/ZwQueryDirectoryFile from a specific application from Minifilter. The goal is for the application to see a folder that doesn't exist. So if the app enumerates files and folders from an empty folder C:\Temp, that application shouldn't see that the folder is empty, instead it should see a folder in that directory (that I will provide in output result).

For this, I have defined a post operation callback for IRP_MJ_DIRECTORY_CONTROL and from there I return one more _FILE_BOTH_DIR_INFORMATION containing data about my "virtual" directory. All's good, I can see the directory from cmd.exe and explorer, but the problem is that the name is corrupted and after banging my head on it for 2 days, can't seem to find the solution.

I added the code Here for ease of readability.

When I load my minifilter, as I said, I can see my virtual directory, but instead of "helloWorld", it gets truncated to "oWorld" in explorer. In cmd, last char (d) gets truncated only. See attached screenshot.

Any idea what am I doing wrong?



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