This patch changes the implementation of strnlen_user in include/asm-generic/uaccess.h.
Originally, it calls strlen() function directly, which may not correctly handle the access of
user space in most mmu-enabled architectures.
New __strnlen_user is added for using as an architecture specific function.

Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

There's no reason that I can see to use the short __access_ok() form
directly when the access_ok() is clearer in intent and for most people,
expands to the same C code (i.e. always specify the first field -- access
type).  Not all no-mmu systems lack memory protection, so the read/write
could feasibly be checked.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

The strnlen_user() function was missing a access_ok() check on the pointer
given.  We've had cases on Blackfin systems where test programs caused
kernel crashes here because userspace passed up a NULL/-1 pointer and the
kernel gladly attempted to run strlen() on it.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Based on discussions with Michal Simek and code
from m68knommu and h8300, this version of uaccess.h
should be usable by most architectures, by overriding
some parts of it.

Simple NOMMU architectures can use it out of
the box, but a minimal __access_ok() should be
added there as well.

Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

The current asm-generic/page.h only contains the get_order
function, and asm-generic/uaccess.h only implements
unaligned accesses. This renames the file to getorder.h
and uaccess-unaligned.h to make room for new page.h
and uaccess.h file that will be usable by all simple
(e.g. nommu) architectures.

Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!