DOCUMENT:Q246691 08-MAY-2002 [winnt] TITLE :The CreateRemoteThread API May Leak a Handle PRODUCT :Microsoft Windows NT PROD/VER::4.0,4.0 SP4,4.0 SP5,4.0 SP6 OPER/SYS: KEYWORDS:kbenv kbWinNT400PreSP7Fix ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server versions 4.0, 4.0 SP4, 4.0 SP5, 4.0 SP6 - Microsoft Windows NT Server, Enterprise Edition versions 4.0, 4.0 SP4, 4.0 SP5, 4.0 SP6 - Microsoft Windows NT Workstation versions 4.0, 4.0 SP4, 4.0 SP5, 4.0 SP6 ------------------------------------------------------------------------------- SYMPTOMS ======== The CreateRemoteThread application programming interface (API) may leak a handle when it is unsuccessful and return a null handle. This increases a handle count of the process that calls the CreateRemoteThread function. Because the handle is null, the calling process cannot close the handle, which results in a memory leak. NOTE: To detect the handle leak, use Performance Monitor and monitor the Handle Count for the process that calls the CreateRemoteThread API. CAUSE ===== The CreateRemoteThread function first successfully creates a thread where it creates a thread handle. If the function is unsuccessful in the later stages of processing, the created thread is terminated and the open handle to this thread is not closed. This open handle causes a memory leak. RESOLUTION ========== A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article and should be applied only to systems experiencing this specific problem. To resolve this problem, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web: http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS NOTE: In special cases, charges that are normally incurred for support calls may be canceled, if a Microsoft Support Professional determines that a specific update will resolve your problem. Normal support costs will apply to additional support questions and issues that do not qualify for the specific update in question. The English version of this fix should have the following file attributes or later: Date Time Size File name Platform ----------------------------------------------------- 11/18/99 04:19pm 375,056 Kernel32.dll Intel 11/18/99 06:17pm 589,584 Kernel32.dll Alpha STATUS ====== Microsoft has confirmed this to be a problem in Windows NT 4.0. Additional query words: ====================================================================== Keywords : kbenv kbWinNT400PreSP7Fix Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTW400sp5 kbWinNTW400sp4 kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400sp6 kbWinNTSEnt400sp5 kbWinNTSEnt400sp4 kbWinNTSEnt400 kbWinNTS400sp6 kbWinNTS400sp5 kbWinNTS400sp4 kbWinNTS400search kbWinNTS400 kbWinNTW400sp6 Version : :4.0,4.0 SP4,4.0 SP5,4.0 SP6 Hardware : ALPHA x86 Issue type : kbbug Solution Type : kbfix ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2002.