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[WIN32K] Fix wrong calculation in DIB_32BPP_BitBltSrcCopy

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Using an unsigned integer will cause the calculations to be unsigned, which on x64 leads to wrong results, when adding it to a pointer.
This commit is contained in:
Timo Kreuzer 2021-05-23 14:02:09 +02:00
parent f0bee6c4bc
commit 50c9dab6c9
1 changed files with 4 additions and 4 deletions
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8
win32ss/gdi/dib/dib32bpp.c
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@ -58,7 +58,8 @@ DIB_32BPP_BitBltSrcCopy(PBLTINFO BltInfo)
PBYTE SourceBitsT, SourceBitsB, DestBitsT, DestBitsB;
PBYTE SourceBits_4BPP, SourceLine_4BPP;
PDWORD Source32, Dest32;
DWORD Index, DestWidth, DestHeight;
DWORD Index;
LONG DestWidth, DestHeight;
BOOLEAN bTopToBottom, bLeftToRight;
BOOLEAN blDeltaSrcNeg, blDeltaDestNeg;
BOOLEAN blDeltaAdjustDone = FALSE;
@ -365,10 +366,9 @@ DIB_32BPP_BitBltSrcCopy(PBLTINFO BltInfo)
{
/* SourceBits points to bottom-left pixel for lDelta < 0 and top-left for lDelta > 0 */
SourceBits = (PBYTE)BltInfo->SourceSurface->pvScan0
+ ((BltInfo->SourcePoint.y
+ DestHeight - 1) * BltInfo->SourceSurface->lDelta)
+ ((BltInfo->SourcePoint.y + DestHeight - 1) * BltInfo->SourceSurface->lDelta)
+ 4 * BltInfo->SourcePoint.x;
/* SourceBits points to bottom-left pixel for lDelta < 0 and top-left for lDelta > 0 */
/* DestBits points to bottom-left pixel for lDelta < 0 and top-left for lDelta > 0 */
DestBits = (PBYTE)BltInfo->DestSurface->pvScan0
+ ((BltInfo->DestRect.bottom - 1) * BltInfo->DestSurface->lDelta)
+ 4 * BltInfo->DestRect.left;