Date: Tue, 25 Apr 2017 19:25:49 +0100
From: Catalin Marinas <catalin.marinas@arm.com>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, a.hajda@samsung.com,
        geert@linux-m68k.org, Laura Abbott <labbott@redhat.com>,
        robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] drivers: dma-mapping: Do not leave an invalid
 area->pages pointer in dma_common_contiguous_remap()
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On Tue, Apr 25, 2017 at 07:22:23PM +0100, Catalin Marinas wrote:
> The dma_common_pages_remap() function allocates a vm_struct object and
> initialises the pages pointer to value passed as argument. However, when
> this function is called dma_common_contiguous_remap(), the pages array
> is only temporarily allocated, being freed shortly after
> dma_common_contiguous_remap() returns. Architecture code checking the
> validity of an area->pages pointer would incorrectly dereference already
> freed pointers. This has been exposed by the arm64 commit 44176bb38fa4
> ("arm64: Add support for DMA_ATTR_FORCE_CONTIGUOUS to IOMMU").
> 
> Fixes: 513510ddba96 ("common: dma-mapping: introduce common remapping functions")
> Cc: Laura Abbott <labbott@redhat.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Reported-by: Andrzej Hajda <a.hajda@samsung.com>
> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Small correction on the subject, the prefix should be something like:

drivers: dma-mapping:

It's not an arm64 patch.

-- 
Catalin