LibGfx: Protect against over-large bitmaps

This commit is contained in:
Ben Wiederhake 2020-08-30 14:18:54 +02:00 committed by Andreas Kling
parent 98bfcb4b57
commit 52a797afdb
Notes: sideshowbarker 2024-07-19 02:45:20 +09:00

View file

@ -44,11 +44,16 @@
namespace Gfx {
static bool size_would_overflow(BitmapFormat format, const IntSize& size)
static bool size_would_overflow(BitmapFormat, const IntSize& size)
{
if (size.width() < 0 || size.height() < 0)
return true;
return Checked<size_t>::multiplication_would_overflow(size.width(), size.height(), Bitmap::bpp_for_format(format));
// This check is a bit arbitrary, but should protect us from most shenanigans:
if (size.width() >= 32768 || size.height() >= 32768)
return true;
// This check is absolutely necessary. Note that Bitmap::Bitmap always stores
// data as RGBA32 internally, so currently we ignore the indicated format.
return Checked<size_t>::multiplication_would_overflow(size.width(), size.height(), sizeof(RGBA32));
}
RefPtr<Bitmap> Bitmap::create(BitmapFormat format, const IntSize& size)