[PATCH] mm: fix remap_pte_range BUG

Out-of-tree user of remap_pfn_range hit kernel BUG at mm/memory.c:1112!  It
passes an unrounded size to remap_pfn_range, which was okay before 2.6.12,
but misses remap_pte_range's new end condition.  An audit of all the other
ptwalks confirms that this is the only one so exposed.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/mm/memory.c b/mm/memory.c
index c256175742ac8612ab49d542ead03efc50789a3c..beabdefa6254a521da762d3a7c44274b29553edd 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1139,7 +1139,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
 {
        pgd_t *pgd;
        unsigned long next;
-       unsigned long end = addr + size;
+       unsigned long end = addr + PAGE_ALIGN(size);
        struct mm_struct *mm = vma->vm_mm;
        int err;