Return strucure from function - c++

Question

hi have this 2 pieces of code in my program:
PIMAGE_IMPORT_DESCRIPTOR PE::GetImportedLibInfo(LPSTR libName )
{
PIMAGE_DOS_HEADER doshdr = (PIMAGE_DOS_HEADER)EntryPoint;
PIMAGE_NT_HEADERS nthdr = (PIMAGE_NT_HEADERS)((DWORD)doshdr + doshdr->e_lfanew);
DWORD tmp =nthdr->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress;
DWORD Rva = RvaToOffset((DWORD)tmp);
if(Rva != -1)
{
Rva += EntryPoint;
PIMAGE_IMPORT_DESCRIPTOR iid =(PIMAGE_IMPORT_DESCRIPTOR)(DWORD)Rva;
while(iid->Characteristics)
{
char* dll = (char*)((DWORD_PTR)RvaToOffset(iid->Name)+ EntryPoint);
DWORD res=lstrcmp((LPCSTR)dll,(LPCSTR)libName);
if(res == 0)
{
return iid;
}
iid ++;
}
}
return NULL;
}
VOID FillLibInfo(PIMAGE_IMPORT_DESCRIPTOR iiD)
{
if(iiD != NULL)
{
char* buff[20];
wsprintf((LPSTR)&buff,"%08lX",(DWORD)iiD->OriginalFirstThunk);
SetDlgItemText(hImpDlg,IDC_EDIT1,(LPCSTR)&buff);
wsprintf((LPSTR)&buff,"%08lX",(DWORD)iiD->TimeDateStamp);
SetDlgItemText(hImpDlg,IDC_EDIT2,(LPCSTR)&buff);
wsprintf((LPSTR)&buff,"%08lX",(DWORD)iiD->ForwarderChain);
SetDlgItemText(hImpDlg,IDC_EDIT3,(LPCSTR)&buff);
wsprintf((LPSTR)&buff,"%08lX",(DWORD)iiD->FirstThunk);
SetDlgItemText(hImpDlg,IDC_EDIT4,(LPCSTR)&buff);
}
}
And then i use it so:
FillLibInfo(GetImportedLibInfo("MyLibName"));
what append is that my textboxes don't actualize text until i pass mouse hover them
and after a couple of calls to GetImportedLibInfo() the program crash.
i think that is something with stack corrupted...
can someone give me a hint?
#Edit:
Class PE defenition:
class PE
{
private:
DWORD ptrImgDosHeader;
DWORD RvaToOffset(DWORD Rva);
DWORD RvaToMemory(DWORD Rva);
public:
DWORD EntryPoint;
PE(DWORD ptrMemory);
~PE();
VOID EnumSections(BOOL (*ptrCallBack)(PIMAGE_SECTION_HEADER));
VOID EnumImports(BOOL (*ptrCallBack)(LPSTR,DWORD),DWORD);
VOID EnumImportedFunctionsFromLib(LPSTR,BOOL (*ptrCallBack)(LPSTR,LPSTR));
VOID EnumExportedFunctions(BOOL (*ptrCallBack)(LPSTR,LPSTR,LPSTR));
WORD GetPeType();
DWORD ValidatePE();
DWORD ValidateNtHeader();
PIMAGE_IMPORT_DESCRIPTOR GetImportedLibInfo(LPSTR lib);
};

Answer 1

You're writing a string to a char pointer array, not a char array, so you're writing to some random pointer (whatever the uninitialised array's first element is pointing to, which will be unallocated memory).
Try using char buff[20] instead of char* buff[20], then use wsprintf( buff, ... ) and SetDlgItemText( ..., buff ).