Messages in this thread Patch in this message | | | Subject | Re: [PATCH] Fix range check on mmaped sysfs resource files | From | Ed Swierk <> | Date | Tue, 28 Oct 2008 22:36:35 -0700 |
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On Tue, 2008-10-28 at 22:24 -0700, Ed Swierk wrote: > pci_mmap_fits() in 2.6.27.4 returns the wrong answer if the sysfs > resource file size is not a multiple of the page size. vm_end and > vm_start are already page-aligned, so size - start < nr, causing > mmap() to return EINVAL. > > Signed-off-by: Ed Swierk <eswierk@aristanetworks.com>
...and here is the patch in a hopefully more readable form.
Index: linux-2.6.27.4/drivers/pci/pci-sysfs.c =================================================================== --- linux-2.6.27.4.orig/drivers/pci/pci-sysfs.c +++ linux-2.6.27.4/drivers/pci/pci-sysfs.c @@ -492,7 +492,7 @@ static int pci_mmap_fits(struct pci_dev nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; start = vma->vm_pgoff; - size = pci_resource_len(pdev, resno) >> PAGE_SHIFT; + size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1; if (start < size && size - start >= nr) return 1; WARN(1, "process \"%s\" tried to map 0x%08lx-0x%08lx on %s BAR %d (size 0x%08lx)\n", | |