The vulnerability is related to the drm/fbdev-dma module in the Linux kernel. It occurs when the `smem start` is set, which can break systems where DMA memory is backed by vmalloc address space. The issue arises because DMA memory is assumed to be contiguous in physical address space, which is not guaranteed by `vmalloc()`. To resolve this, the module flag `drm leak fbdev smem` should be checked when DRM allocates the instance of `struct fb info`. The `fbdev-dma` then only sets `smem start` if required, and the framebuffer should not be located in `vmalloc` address space.