tree edebc20a9689231fd62d857d9a9e51f9bf3850c3
parent cb3d6759a93c6d0aea1c10deb6d00e111c29c19c
author Michael Ellerman <mpe@ellerman.id.au> 1524543358 +1000
committer Michael Ellerman <mpe@ellerman.id.au> 1528022625 +1000

powerpc: Use barrier_nospec in copy_from_user()

Based on the x86 commit doing the same.

See commit 304ec1b05031 ("x86/uaccess: Use __uaccess_begin_nospec()
and uaccess_try_nospec") and b3bbfb3fb5d2 ("x86: Introduce
__uaccess_begin_nospec() and uaccess_try_nospec") for more detail.

In all cases we are ordering the load from the potentially
user-controlled pointer vs a previous branch based on an access_ok()
check or similar.

Base on a patch from Michal Suchanek.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>