[PATCH] mprotect propagate anon_vma

[PATCH] mprotect propagate anon_vma

When mprotect shifts the boundary between vmas (merging the reprotected
area into the vma before or the vma after), make sure that the expanding
vma has anon_vma if the shrinking vma had, to cover anon pages imported.
Thanks to Andrea for alerting us to this oversight.

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