From 286c21de32b904131f8cf6a36ce40b8b0c9c5da3 Mon Sep 17 00:00:00 2001 From: Kevin Grandemange Date: Thu, 12 Mar 2020 15:41:45 +0000 Subject: dma-coherent: fix integer overflow in the reserved-memory dma allocation pageno is an int and the PAGE_SHIFT shift is done on an int, overflowing if the memory is bigger than 2G This can be reproduced using for example a reserved-memory of 4G reserved-memory { #address-cells = <2>; #size-cells = <2>; ranges; reserved_dma: buffer@0 { compatible = "shared-dma-pool"; no-map; reg = <0x5 0x00000000 0x1 0x0>; }; }; Signed-off-by: Kevin Grandemange Signed-off-by: Christoph Hellwig --- kernel/dma/coherent.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c index 551b0eb7028a..2a0c4985f38e 100644 --- a/kernel/dma/coherent.c +++ b/kernel/dma/coherent.c @@ -134,7 +134,7 @@ static void *__dma_alloc_from_coherent(struct device *dev, spin_lock_irqsave(&mem->spinlock, flags); - if (unlikely(size > (mem->size << PAGE_SHIFT))) + if (unlikely(size > ((dma_addr_t)mem->size << PAGE_SHIFT))) goto err; pageno = bitmap_find_free_region(mem->bitmap, mem->size, order); @@ -144,8 +144,9 @@ static void *__dma_alloc_from_coherent(struct device *dev, /* * Memory was found in the coherent area. */ - *dma_handle = dma_get_device_base(dev, mem) + (pageno << PAGE_SHIFT); - ret = mem->virt_base + (pageno << PAGE_SHIFT); + *dma_handle = dma_get_device_base(dev, mem) + + ((dma_addr_t)pageno << PAGE_SHIFT); + ret = mem->virt_base + ((dma_addr_t)pageno << PAGE_SHIFT); spin_unlock_irqrestore(&mem->spinlock, flags); memset(ret, 0, size); return ret; @@ -194,7 +195,7 @@ static int __dma_release_from_coherent(struct dma_coherent_mem *mem, int order, void *vaddr) { if (mem && vaddr >= mem->virt_base && vaddr < - (mem->virt_base + (mem->size << PAGE_SHIFT))) { + (mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) { int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; unsigned long flags; @@ -238,10 +239,10 @@ static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem, struct vm_area_struct *vma, void *vaddr, size_t size, int *ret) { if (mem && vaddr >= mem->virt_base && vaddr + size <= - (mem->virt_base + (mem->size << PAGE_SHIFT))) { + (mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) { unsigned long off = vma->vm_pgoff; int start = (vaddr - mem->virt_base) >> PAGE_SHIFT; - int user_count = vma_pages(vma); + unsigned long user_count = vma_pages(vma); int count = PAGE_ALIGN(size) >> PAGE_SHIFT; *ret = -ENXIO; -- cgit From 3d0fc341c4bb66b2c41c0d1ec954a6d300e100b7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 21 Feb 2020 12:26:00 -0800 Subject: dma-direct: consolidate the error handling in dma_direct_alloc_pages Use a goto label to merge two error return cases. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- kernel/dma/direct.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 6af7ae83c4ad..650580fbbff3 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -169,11 +169,8 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, ret = dma_common_contiguous_remap(page, PAGE_ALIGN(size), dma_pgprot(dev, PAGE_KERNEL, attrs), __builtin_return_address(0)); - if (!ret) { - dma_free_contiguous(dev, page, size); - return ret; - } - + if (!ret) + goto out_free_pages; memset(ret, 0, size); goto done; } @@ -186,8 +183,7 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, * so log an error and fail. */ dev_info(dev, "Rejecting highmem page from CMA.\n"); - dma_free_contiguous(dev, page, size); - return NULL; + goto out_free_pages; } ret = page_address(page); @@ -207,6 +203,9 @@ done: else *dma_handle = phys_to_dma(dev, page_to_phys(page)); return ret; +out_free_pages: + dma_free_contiguous(dev, page, size); + return NULL; } void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, -- cgit From fa7e2247c5729f990c7456fe09f3af99c8f2571b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 21 Feb 2020 15:55:43 -0800 Subject: dma-direct: make uncached_kernel_address more general Rename the symbol to arch_dma_set_uncached, and pass a size to it as well as allow an error return. That will allow reusing this hook for in-place pagetable remapping. As the in-place remap doesn't always require an explicit cache flush, also detangle ARCH_HAS_DMA_PREP_COHERENT from ARCH_HAS_DMA_SET_UNCACHED. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- kernel/dma/direct.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 650580fbbff3..baf4e93735c3 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -192,10 +192,12 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, memset(ret, 0, size); - if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && dma_alloc_need_uncached(dev, attrs)) { arch_dma_prep_coherent(page, size); - ret = uncached_kernel_address(ret); + ret = arch_dma_set_uncached(ret, size); + if (IS_ERR(ret)) + goto out_free_pages; } done: if (force_dma_unencrypted(dev)) @@ -236,7 +238,7 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { - if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && dma_alloc_need_uncached(dev, attrs)) return arch_dma_alloc(dev, size, dma_handle, gfp, attrs); @@ -246,7 +248,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { - if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && dma_alloc_need_uncached(dev, attrs)) arch_dma_free(dev, size, cpu_addr, dma_addr, attrs); -- cgit From 999a5d1203baa7cff00586361feae263ee3f23a5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 21 Feb 2020 12:35:05 -0800 Subject: dma-direct: provide a arch_dma_clear_uncached hook This allows the arch code to reset the page tables to cached access when freeing a dma coherent allocation that was set to uncached using arch_dma_set_uncached. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- kernel/dma/direct.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel') diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index baf4e93735c3..412f560dc69f 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -231,6 +231,8 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, if (IS_ENABLED(CONFIG_DMA_REMAP) && is_vmalloc_addr(cpu_addr)) vunmap(cpu_addr); + else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED)) + arch_dma_clear_uncached(cpu_addr, size); dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size); } -- cgit