| Message ID | 20210723010552.50969-1-ezequiel@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iommu/dma: Fix leak in non-contiguous API | expand |
Looks good, Reviewed-by: Christoph Hellwig <hch@lst.de> > As a side note, it appears the struct dma_sgt_handle type is exposed > to users of the DMA-API by linux/dma-map-ops.h, but is has no users > or functions returning the type explicitly. > > This may indicate it's a good idea to move the struct dma_sgt_handle type > to drivers/iommu/dma-iommu.c. The decision is left to maintainers :-) linux/dma-map-ops.h is a helper header for the dma_ops implementations, not for users of the DMA API. sgt_handle, which references dma_sgt_handle is used in kernel/dma/mapping.c
On Thu, Jul 22, 2021 at 10:05:52PM -0300, Ezequiel Garcia wrote: > drivers/iommu/dma-iommu.c | 1 + > 1 file changed, 1 insertion(+) Applied to iommu/fixes, thanks.
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 4e34e8b26579..16c06a1aab80 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -768,6 +768,7 @@ static void iommu_dma_free_noncontiguous(struct device *dev, size_t size, __iommu_dma_unmap(dev, sgt->sgl->dma_address, size); __iommu_dma_free_pages(sh->pages, PAGE_ALIGN(size) >> PAGE_SHIFT); sg_free_table(&sh->sgt); + kfree(sh); } #endif /* CONFIG_DMA_REMAP */
Currently, iommu_dma_alloc_noncontiguous() allocates a struct dma_sgt_handle object to hold some state needed for iommu_dma_free_noncontiguous(). However, the handle is neither freed nor returned explicitly by the ->alloc_noncontiguous method, and therefore seems leaked. This was found by code inspection, so please review carefully and test. As a side note, it appears the struct dma_sgt_handle type is exposed to users of the DMA-API by linux/dma-map-ops.h, but is has no users or functions returning the type explicitly. This may indicate it's a good idea to move the struct dma_sgt_handle type to drivers/iommu/dma-iommu.c. The decision is left to maintainers :-) Cc: stable@vger.kernel.org Fixes: e817ee5f2f95c ("dma-iommu: implement ->alloc_noncontiguous") Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com> --- drivers/iommu/dma-iommu.c | 1 + 1 file changed, 1 insertion(+)