static inline void SetPSDPixel(Image *image,const size_t channels,
  const ssize_t type,const size_t packet_size,const Quantum pixel,Quantum *q,
  ExceptionInfo *exception)
{
  if (image->storage_class == PseudoClass)
    {
      if (packet_size == 1)
        SetPixelIndex(image,ScaleQuantumToChar(pixel),q);
      else
        SetPixelIndex(image,ScaleQuantumToShort(pixel),q);
      SetPixelViaPixelInfo(image,image->colormap+(ssize_t)
        ConstrainColormapIndex(image,GetPixelIndex(image,q),exception),q);
      return;
    }
  switch (type)
  {
    case -1:
    {
      SetPixelAlpha(image, pixel,q);
      break;
    }
    case -2:
    case 0:
    {
      SetPixelRed(image,pixel,q);
      if (channels == 1 || type == -2)
        SetPixelGray(image,pixel,q);
      break;
    }
    case 1:
    {
      if (image->storage_class == PseudoClass)
        SetPixelAlpha(image,pixel,q);
      else
        SetPixelGreen(image,pixel,q);
      break;
    }
    case 2:
    {
      if (image->storage_class == PseudoClass)
        SetPixelAlpha(image,pixel,q);
      else
        SetPixelBlue(image,pixel,q);
      break;
    }
    case 3:
    {
      if (image->colorspace == CMYKColorspace)
        SetPixelBlack(image,pixel,q);
      else
        if (image->alpha_trait != UndefinedPixelTrait)
          SetPixelAlpha(image,pixel,q);
      break;
    }
    case 4:
    {
      if ((IssRGBCompatibleColorspace(image->colorspace) != MagickFalse) &&
          (channels > 3))
        break;
      if (image->alpha_trait != UndefinedPixelTrait)
        SetPixelAlpha(image,pixel,q);
      break;
    }
  }
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.