PATCH: Fix offset of mmap

["H . J . Lu" <hjl@lucon.org>]

We should check if offset of mmap is on the page boundary.


H.J.
---
--- /tmp/tmp.20947.0	Fri Sep 14 10:05:33 2001
+++ arch/mips/kernel/syscall.c	Fri Sep 14 10:05:08 2001
@@ -82,6 +82,8 @@ out:
 asmlinkage unsigned long old_mmap(unsigned long addr, size_t len, int prot,
                                   int flags, int fd, off_t offset)
 {
+	if (offset & ~PAGE_MASK)
+		return -EINVAL;
 	return do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 }