Myah Caron : dmband: Avoid cloning stream in parse_bands_list.

[Alexandre Julliard]

Module: wine
Branch: oldstable
Commit: a0f1cf0449bc8225720ad38702d0235886c6da5e
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=a0f1cf0449bc8225720ad3870...

Author: Myah Caron 
Date:   Thu Sep 17 05:18:08 2020 -0700

dmband: Avoid cloning stream in parse_bands_list.

A stream that doesn't implement ::Clone can be passed, causing IStream_Seek to crash.

Signed-off-by: Myah Caron 
Signed-off-by: Michael Stefaniuc 
Signed-off-by: Alexandre Julliard 
(cherry picked from commit 2cf69bb5a5b43951abb251f415ccb81e809bd32e)
Signed-off-by: Michael Stefaniuc

---

dlls/dmband/bandtrack.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/dlls/dmband/bandtrack.c b/dlls/dmband/bandtrack.c
index 14d2c7a571c..612be063e19 100644
--- a/dlls/dmband/bandtrack.c
+++ b/dlls/dmband/bandtrack.c
@@ -425,21 +425,22 @@ static HRESULT parse_bands_list(IDirectMusicBandTrack *This, DMUS_PRIVATE_CHUNK
      StreamSize = Chunk.dwSize - sizeof(FOURCC);
      switch (Chunk.fccID) {
      case DMUS_FOURCC_BAND_FORM: {
-	    LPSTREAM pClonedStream = NULL;
+	    ULARGE_INTEGER liOrigPos;
        TRACE_(dmfile)(": BAND RIFF\n");
-	    
-	    IStream_Clone (pStm, &pClonedStream);
-	    
+
        liMove.QuadPart = 0;
+	    IStream_Seek (pStm, liMove, STREAM_SEEK_CUR, &liOrigPos);
+
        liMove.QuadPart -= sizeof(FOURCC) + (sizeof(FOURCC)+sizeof(DWORD));
-	    IStream_Seek (pClonedStream, liMove, STREAM_SEEK_CUR, NULL);
+	    IStream_Seek (pStm, liMove, STREAM_SEEK_CUR, NULL);

-            hr = load_band(This, pClonedStream, &pBand, &header);
+            hr = load_band(This, pStm, &pBand, &header);
        if (FAILED(hr)) {
          ERR(": could not load track\n");
          return hr;
        }
-	    IStream_Release (pClonedStream);
+	    liMove.QuadPart = (LONGLONG)liOrigPos.QuadPart;
+	    IStream_Seek (pStm, liMove, STREAM_SEEK_SET, NULL);
        
        IDirectMusicTrack_Release(pBand); pBand = NULL; /* now we can release at as it inserted */