Microsoft KB Archive/111591

{|
 * width="100%"|

BUG: IsBadStringPtr Reports Bad String as Valid

 * }

Q111591

-

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 
 * 1) include 
 * 2) 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 :

Issue type :

Technology : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK310