When displaying the Summary Info for an existing DrawCli file with
Summary Info saved, DrawCli may crash with the following error:
Unhandled Exception : Access Violation
DrawCli is an MFC OLE sample that is shipped with Visual C++.
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CSummInfo::ReadFromStorage does not set CSummInfo::m_pSection. This
behavior leaves a dangling pointer into memory that has been deleted.
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Modify the ReadFromStorage as follows:
BOOL CSummInfo::ReadFromStorage( LPSTORAGE lpRootStg )
{
if (lpRootStg != NULL)
{
LPSTREAM lpStream = NULL;
if (FAILED(lpRootStg->OpenStream( szSummInfo,
NULL, STGM_SHARE_EXCLUSIVE|STGM_READ,
0, &lpStream )))
{
TRACE(_T("OpenStream failed\n"));
return FALSE;
}
else
{
if (!m_propSet.ReadFromStream( lpStream ))
{
TRACE(_T("ReadFromStream failed\n"));
return FALSE;
}
// add the following line
m_pSection = m_propSet.GetSection(FMTID_SummaryInformation);
lpStream->Release();
return TRUE;
}
}
return FALSE;
}
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Microsoft has confirmed this to be a bug in the Microsoft products
listed at the beginning of this article. This bug was corrected in
Visual C++ version 4.2.
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