windowscodecs: Check IFD structure when loading metadata.

oldstable
Dmitry Timoshkov 2012-06-13 18:31:09 +09:00 committed by Alexandre Julliard
parent 5f22fdb86f
commit 7cf036a471
2 changed files with 34 additions and 0 deletions

View File

@ -733,6 +733,39 @@ static HRESULT LoadIfdMetadata(IStream *input, const GUID *preferred_vendor,
return hr;
}
/* limit number of IFDs to 4096 to avoid infinite loop */
for (i = 0; i < 4096; i++)
{
ULONG next_ifd_offset;
LARGE_INTEGER pos;
USHORT next_ifd_count;
hr = IStream_Read(input, &next_ifd_offset, sizeof(next_ifd_offset), NULL);
if (FAILED(hr)) break;
SWAP_ULONG(next_ifd_offset);
if (!next_ifd_offset) break;
pos.QuadPart = next_ifd_offset;
hr = IStream_Seek(input, pos, SEEK_SET, NULL);
if (FAILED(hr)) break;
hr = IStream_Read(input, &next_ifd_count, sizeof(next_ifd_count), NULL);
if (FAILED(hr)) break;
SWAP_USHORT(next_ifd_count);
pos.QuadPart = next_ifd_count * sizeof(*entry);
hr = IStream_Seek(input, pos, SEEK_CUR, NULL);
if (FAILED(hr)) break;
}
if (FAILED(hr) || i == 4096)
{
HeapFree(GetProcessHeap(), 0, entry);
return WINCODEC_ERR_BADMETADATAHEADER;
}
result = HeapAlloc(GetProcessHeap(), 0, count * sizeof(*result));
if (!result)
{

View File

@ -206,6 +206,7 @@ cpp_quote("#define WINCODEC_ERR_CODECNOTHUMBNAIL 0x88982f44")
cpp_quote("#define WINCODEC_ERR_PALETTEUNAVAILABLE 0x88982f45")
cpp_quote("#define WINCODEC_ERR_COMPONENTNOTFOUND 0x88982f50")
cpp_quote("#define WINCODEC_ERR_FRAMEMISSING 0x88982f62")
cpp_quote("#define WINCODEC_ERR_BADMETADATAHEADER 0x88982f63")
cpp_quote("#define WINCODEC_ERR_UNSUPPORTEDPIXELFORMAT 0x88982f80")
cpp_quote("#define WINCODEC_ERR_UNSUPPORTEDOPERATION 0x88982f81")
cpp_quote("#define WINCODEC_ERR_INSUFFICIENTBUFFER 0x88982f8c")