DOCUMENT:Q111591 06-NOV-1999 [win16sdk] TITLE :BUG: IsBadStringPtr() Reports Bad String as Valid PRODUCT :Microsoft Windows Software Development Kit PROD/VER:WINDOWS:3.1 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows Software Development Kit (SDK) 3.1 ------------------------------------------------------------------------------- SYMPTOMS ======== Under a particular condition, IsBadStringPtr() will report that a bad string is valid. If the pointer passed to IsBadStringPtr() refers to a block of memory of size 0xFFFF and is filled with all nonzero data, IsBadStringPtr() returns 0. STATUS ====== Microsoft has confirmed this to be a bug in Windows version 3.1. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available. MORE INFORMATION ================ For IsBadStringPtr() to validate a string, it must be passed a pointer to valid memory and the string must contain a NULL character that terminates the string. The following code illustrates the error: #include #include #include LPSTR lpPtr; BOOL fRet; // GlobalAllocPtr is a macro in WINDOWSX.H lpPtr = GlobalAllocPtr(GMEM_MOVEABLE, 0XFFFF); _fmemset(lpPtr, 'Q', 0xFFFF); Ret = IsBadStringPtr(lpPtr, 0xFFFF); if (fRet) // ... etcetera, fRet incorrectly contains zero. Additional query words: buglist3.10 3.10 ====================================================================== Keywords : Technology : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK310 Version : WINDOWS:3.1 ============================================================================= 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 1999.