From 6f1184dfc0ec6dd1fd24b284737a68b05ffbb61c Mon Sep 17 00:00:00 2001 From: Jan Holesovsky Date: Thu, 3 Sep 2015 16:52:59 +0200 Subject: tdf#93892: Un-share maUserBuffer when the BitmapWriteAccess is requested. Otherwise Bad Things Happen, and we may accidentally overwrite random other / shared data. Change-Id: I463354a6e910a2cb43faa229708fe5c14c79535a --- vcl/opengl/salbmp.cxx | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/vcl/opengl/salbmp.cxx b/vcl/opengl/salbmp.cxx index 4ed2ed06b65c..9084ae17dcde 100644 --- a/vcl/opengl/salbmp.cxx +++ b/vcl/opengl/salbmp.cxx @@ -141,9 +141,15 @@ bool OpenGLSalBitmap::Create( const SalBitmap& rSalBmp, sal_uInt16 nNewBitCount // execute any pending operations on the source bitmap maTexture = rSourceBitmap.GetTexture(); mbDirtyTexture = false; + + // be careful here, we are share & reference-count the + // maUserBuffer, BUT this Create() is called from + // Bitmap::ImplMakeUnique(). + // Consequently, there might be cases when this needs to be made + // unique later (when we don't do that right away here), like when + // using the BitmapWriteAccess. maUserBuffer = rSourceBitmap.maUserBuffer; - // TODO Copy buffer data if the bitcount and palette are the same return true; } return false; @@ -649,6 +655,16 @@ BitmapBuffer* OpenGLSalBitmap::AcquireBuffer( BitmapAccessMode nMode ) } } + // maUserBuffer must be unique when we are doing the write access + if (nMode == BITMAP_WRITE_ACCESS && maUserBuffer && !maUserBuffer.unique()) + { + basebmp::RawMemorySharedArray aBuffer(maUserBuffer); + + maUserBuffer.reset(); + AllocateUserData(); + memcpy(maUserBuffer.get(), aBuffer.get(), static_cast(mnBytesPerRow) * mnHeight); + } + BitmapBuffer* pBuffer = new BitmapBuffer; pBuffer->mnWidth = mnWidth; pBuffer->mnHeight = mnHeight; -- cgit v1.2.1