FIX: Memory Leak Using UDP Socket Under Windows CE 2.0

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View products that this article applies to.

This article was previously published under Q183364

SYMPTOMS

Under Windows CE, a memory leak exists when you use a UDP (datagram) socket. The leak occurs when you call either the send() or sendto() API on either a connected or unconnected socket, respectively. A call causes a small leak in the kernel. Eventually, the handheld PC runs low on memory, which triggers message boxes detailing the error. As a result, other applications might terminate due to insufficient memory.

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CAUSE

A kernel critical section object in the route cache of the IP layer. Calls to send/sendto on UDP sockets cause a leak per call.

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RESOLUTION

There are no hot fixes available. The only viable solution is to avoid using datagram sockets and use stream sockets instead.

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STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. This problem was corrected Windows CE, version 2.1.

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MORE INFORMATION

Steps to Reproduce Behavior

To reproduce the problem put the following code into a file and compile it using the winsock.lib. This sample code creates a datagram socket and sends out 1 byte of data on each call to the sendto() API.

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Sample Code

   #include <windows.h>
   #include <winsock.h>
   #include <stdlib.h>
   #include <string.h>

   int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                   LPTSTR lpCmdLine, int nCmdShow)
   {
       char    *server_name= "10.255.0.164",  // Send to arbitrary address.
                data[1];
       WSADATA  wsaData;
       SOCKET   conn_socket;
       struct   sockaddr_in server;

       WSAStartup(0x101, &wsaData);

       server.sin_addr.s_addr = inet_addr(server_name);
       server.sin_family = AF_INET;
       server.sin_port   = htons(5001);

       conn_socket = socket(AF_INET, SOCK_DGRAM, 0);

       data[0] = '0';
       while(1)
            sendto(conn_socket, data, 1, 0, (struct sockaddr *)&server,
               sizeof(server));

       closesocket(conn_socket);
       WSACleanup();
   }

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APPLIES TO

Microsoft Windows CE 2.0 for the Handheld PC

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kbapi kbbug kbfix kbip kbnetwork kboswince210fix kbwinsock KB183364

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Retired KB Content Disclaimer

This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.

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