Messages in this thread Patch in this message | | | From | David Howells <> | Subject | [PATCH 1/2] Check if start address is in vma region in NOMMU function get_user_pages(). | Date | Fri, 01 Sep 2006 13:42:07 +0100 |
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From: Sonic Zhang <sonic.adi@gmail.com>
Hi,
In NOMMU arch, if run "cat /proc/self/mem", data from physical address 0 are read. This behavior is different from MMU arch. In IA32, message "cat: /proc/self/mem: Input/output error" is reported.
This issue is rootcaused by not validate the start address in NOMMU function get_user_pages(). Following patch solves this issue.
Thanks
Sonic Zhang
Signed-off-by: Sonic Zhang <sonic.adi@gmail.com> Signed-Off-By: David Howells <dhowells@redhat.com> ---
mm/nommu.c | 8 ++++++-- 1 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/mm/nommu.c b/mm/nommu.c index 3215f46..2fe3fe4 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -129,16 +129,20 @@ int get_user_pages(struct task_struct *t struct page **pages, struct vm_area_struct **vmas) { int i; - static struct vm_area_struct dummy_vma; + struct vm_area_struct *vma; for (i = 0; i < len; i++) { + vma = find_vma(mm, start); + if(!vma) + return i ? : -EFAULT; + if (pages) { pages[i] = virt_to_page(start); if (pages[i]) page_cache_get(pages[i]); } if (vmas) - vmas[i] = &dummy_vma; + vmas[i] = vma; start += PAGE_SIZE; } return(i); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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