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| author | Christoph Hellwig <hch@lst.de> | 2019-07-08 11:51:56 -0700 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2019-07-24 17:28:54 +0200 |
| commit | 66d7780f18eae0232827fcffeaded39a6a168236 (patch) | |
| tree | 78bb0a0a0f8a11384dea615cc845185162ea531a /kernel | |
| parent | 06532750010e06dd4b6d69983773677df7fc5291 (diff) | |
| download | linux-66d7780f18eae0232827fcffeaded39a6a168236.tar.bz2 | |
dma-mapping: check pfn validity in dma_common_{mmap,get_sgtable}
Check that the pfn returned from arch_dma_coherent_to_pfn refers to
a valid page and reject the mmap / get_sgtable requests otherwise.
Based on the arm implementation of the mmap and get_sgtable methods.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Vignesh Raghavendra <vigneshr@ti.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/mapping.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 1f628e7ac709..b945239621d8 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -116,11 +116,16 @@ int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, int ret; if (!dev_is_dma_coherent(dev)) { + unsigned long pfn; + if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN)) return -ENXIO; - page = pfn_to_page(arch_dma_coherent_to_pfn(dev, cpu_addr, - dma_addr)); + /* If the PFN is not valid, we do not have a struct page */ + pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr); + if (!pfn_valid(pfn)) + return -ENXIO; + page = pfn_to_page(pfn); } else { page = virt_to_page(cpu_addr); } @@ -170,7 +175,11 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, if (!dev_is_dma_coherent(dev)) { if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN)) return -ENXIO; + + /* If the PFN is not valid, we do not have a struct page */ pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr); + if (!pfn_valid(pfn)) + return -ENXIO; } else { pfn = page_to_pfn(virt_to_page(cpu_addr)); } |