From ac2b3e67dd59b8c6ef8c199641444c6ea03535a6 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 15 Dec 2009 16:47:43 -0800 Subject: [PATCH] dma-mapping: fix off-by-one error in dma_capable() dma_mask is, when interpreted as address, the last valid byte, and hence comparison msut also be done using the last valid of the buffer in question. Also fix the open-coded instances in lib/swiotlb.c. Signed-off-by: Jan Beulich Cc: FUJITA Tomonori Cc: Becky Bruce Cc: "Luck, Tony" Cc: Benjamin Herrenschmidt Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/include/asm/dma-mapping.h | 2 +- arch/powerpc/include/asm/dma-mapping.h | 2 +- arch/x86/include/asm/dma-mapping.h | 2 +- lib/swiotlb.c | 4 ++-- 4 files changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/ia64/include/asm/dma-mapping.h b/arch/ia64/include/asm/dma-mapping.h index 8d3c79cd81e7..7d09a09cdaad 100644 --- a/arch/ia64/include/asm/dma-mapping.h +++ b/arch/ia64/include/asm/dma-mapping.h @@ -73,7 +73,7 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) if (!dev->dma_mask) return 0; - return addr + size <= *dev->dma_mask; + return addr + size - 1 <= *dev->dma_mask; } static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) diff --git a/arch/powerpc/include/asm/dma-mapping.h b/arch/powerpc/include/asm/dma-mapping.h index e281daebddca..80a973bb9e71 100644 --- a/arch/powerpc/include/asm/dma-mapping.h +++ b/arch/powerpc/include/asm/dma-mapping.h @@ -197,7 +197,7 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) if (!dev->dma_mask) return 0; - return addr + size <= *dev->dma_mask; + return addr + size - 1 <= *dev->dma_mask; } static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h index 0f6c02f3b7d4..ac91eed21061 100644 --- a/arch/x86/include/asm/dma-mapping.h +++ b/arch/x86/include/asm/dma-mapping.h @@ -67,7 +67,7 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) if (!dev->dma_mask) return 0; - return addr + size <= *dev->dma_mask; + return addr + size - 1 <= *dev->dma_mask; } static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 5bc01803f8f8..437eedb5a53b 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -549,7 +549,7 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size, dma_mask = hwdev->coherent_dma_mask; ret = (void *)__get_free_pages(flags, order); - if (ret && swiotlb_virt_to_bus(hwdev, ret) + size > dma_mask) { + if (ret && swiotlb_virt_to_bus(hwdev, ret) + size - 1 > dma_mask) { /* * The allocated memory isn't reachable by the device. */ @@ -571,7 +571,7 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size, dev_addr = swiotlb_virt_to_bus(hwdev, ret); /* Confirm address can be DMA'd by device */ - if (dev_addr + size > dma_mask) { + if (dev_addr + size - 1 > dma_mask) { printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n", (unsigned long long)dma_mask, (unsigned long long)dev_addr); -- 2.30.2