WinDivert connection loss

问题

I am using WinDivert 1.1.8 MSVC x64 in Visual Studio 2015 along with a P/Invoke wrapper for C# to create a simple latency simulator, but the connection fails when performing bandwidth intensive tasks, such as a speedtest.

Output

ERROR_IO_PENDING 997 (0x3E5) Overlapped I/O operation is in progress.

ERROR_INSUFFICIENT_BUFFER 122 (0x7A) The data area passed to a system call is too small.

Notes

Possible deadlocking caused by x64 remote debugging?

Possibly overwhelming the WinDivert queue?

Update

I have tried parallel threading and this produced the same errors.

Parallel.ForEach(Enumerable.Range(0, Environment.ProcessorCount), x => RunDiversion());

Update 2

After further testing the code the offending line may be:

packet.CopyTo(newpacket.data, 0);

Update 3

CPU Stack WinDivert queue possibly needs marshalling?

回答1:

You should be using WinDivertRecvEx instead of WinDivertRecv to avoid overlapped I/O. Also, you're using Queue<T> on multithreaded app, which I believe you should use ConcurrentQueue<T> instead.

I think x64 debugger may cause problems too. I'm running the app without debugging and it works (CTRL+F5).

Working code: https://gist.github.com/fahminlb33/16f69460466eb07f88e7588a285fb4f8

来源：https://stackoverflow.com/questions/44136191/windivert-connection-loss