Re: [PATCH] dma-buf: cma_heap: Fix memory leak in CMA heap

From: Sumit Semwal
Date: Fri Jan 08 2021 - 22:45:46 EST


Hi John,

On Fri, 8 Jan 2021 at 01:56, John Stultz <john.stultz@xxxxxxxxxx> wrote:
>
> Bing Song noticed the CMA heap was leaking memory due to a flub
> I made in commit a5d2d29e24be ("dma-buf: heaps: Move heap-helper
> logic into the cma_heap implementation"), and provided this fix
> which ensures the pagelist is also freed on release.
Thanks for your patch.
>
> Cc: Bing Song <bing.song@xxxxxxx>
> Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
> Cc: Liam Mark <lmark@xxxxxxxxxxxxxx>
> Cc: Laura Abbott <labbott@xxxxxxxxxx>
> Cc: Brian Starkey <Brian.Starkey@xxxxxxx>
> Cc: Hridya Valsaraju <hridya@xxxxxxxxxx>
> Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Cc: Sandeep Patil <sspatil@xxxxxxxxxx>
> Cc: Daniel Mentz <danielmentz@xxxxxxxxxx>
> Cc: Chris Goldsworthy <cgoldswo@xxxxxxxxxxxxxx>
> Cc: Ørjan Eide <orjan.eide@xxxxxxx>
> Cc: Robin Murphy <robin.murphy@xxxxxxx>
> Cc: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> Cc: Simon Ser <contact@xxxxxxxxxxx>
> Cc: James Jones <jajones@xxxxxxxxxx>
> Cc: linux-media@xxxxxxxxxxxxxxx
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Reported-by: Bing Song <bing.song@xxxxxxx>
> Fixes: a5d2d29e24be ("dma-buf: heaps: Move heap-helper logic into the cma_heap implementation")
> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>

I will queue it up so it gets in the v5.11 cycle.
> ---
> drivers/dma-buf/heaps/cma_heap.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
> index 3c4e34301172..364fc2f3e499 100644
> --- a/drivers/dma-buf/heaps/cma_heap.c
> +++ b/drivers/dma-buf/heaps/cma_heap.c
> @@ -251,6 +251,9 @@ static void cma_heap_dma_buf_release(struct dma_buf *dmabuf)
> buffer->vaddr = NULL;
> }
>
> + /* free page list */
> + kfree(buffer->pages);
> + /* release memory */
> cma_release(cma_heap->cma, buffer->cma_pages, buffer->pagecount);
> kfree(buffer);
> }
> --
> 2.17.1
>
Best,
Sumit.