[PATCH] msync: fix return value

msync() does a strange thing.  Essentially:

	vma = find_vma();
	for ( ; ; ) {
		if (!vma)
			return -ENOMEM;
		...
		vma = vma->vm_next;
	}

so an msync() request which starts within or before a valid VMA and which ends
within or beyond the final VMA will incorrectly return -ENOMEM.

Fix.

Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>