• David Windsor's avatar
    vfs: Copy struct mount.mnt_id to userspace using put_user() · 6391af6f
    David Windsor authored
    The mnt_id field can be copied with put_user(), so there is no need to
    use copy_to_user(). In both cases, hardened usercopy is being bypassed
    since the size is constant, and not open to runtime manipulation.
    
    This patch is verbatim from Brad Spengler/PaX Team's PAX_USERCOPY
    whitelisting code in the last public patch of grsecurity/PaX based on my
    understanding of the code. Changes or omissions from the original code are
    mine and don't reflect the original grsecurity/PaX code.
    Signed-off-by: default avatarDavid Windsor <dave@nullcore.net>
    [kees: adjust commit log]
    Cc: Alexander Viro <viro@zeniv.linux.org.uk>
    Cc: linux-fsdevel@vger.kernel.org
    Signed-off-by: default avatarKees Cook <keescook@chromium.org>
    6391af6f