• Simon Glass's avatar
    arm: Add CONFIG_DELAY_ENVIRONMENT to delay environment loading · 06fd8538
    Simon Glass authored
    This option delays loading of the environment until later, so that only the
    default environment will be available to U-Boot.
    
    This can address the security risk of untrusted data being used during boot.
    
    Any time you load untrusted data you expose yourself to a bug in the
    code. The attacker gets to choose the data so can sometimes carefully
    craft it to exploit a bug. We try to avoid touching user-controlled
    data during a verified boot unless strictly necessary. Since the
    default environment is good enough in this case (or you would just
    change it), this gets around the problem by just not loading the
    environment.
    
    When CONFIG_DELAY_ENVIRONMENT is defined, it is convenient to have a
    run-time way of enabling loading of the environment. Add this to the
    fdt as /config/delay-environment.
    
    Note: This patch depends on http://patchwork.ozlabs.org/patch/194342/
    
    Signed-off-by: default avatarDoug Anderson <dianders@chromium.org>
    Signed-off-by: Simon Glass's avatarSimon Glass <sjg@chromium.org>
    Reviewed-by: default avatarDoug Anderson <dianders@chromium.org>
    06fd8538