lkml.org 
[lkml]   [2021]   [Apr]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v10 05/33] counter: 104-quad-8: Annotate hardware config module parameter
    On Fri, Mar 19, 2021 at 08:00:24PM +0900, William Breathitt Gray wrote:
    > When the kernel is running in secure boot mode, we lock down the kernel to
    > prevent userspace from modifying the running kernel image. Whilst this
    > includes prohibiting access to things like /dev/mem, it must also prevent
    > access by means of configuring driver modules in such a way as to cause a
    > device to access or modify the kernel image.
    >
    > To this end, annotate module_param* statements that refer to hardware
    > configuration and indicate for future reference what type of parameter they
    > specify. The parameter parser in the core sees this information and can
    > skip such parameters with an error message if the kernel is locked down.
    > The module initialisation then runs as normal, but just sees whatever the
    > default values for those parameters is.
    >
    > Note that we do still need to do the module initialisation because some
    > drivers have viable defaults set in case parameters aren't specified and
    > some drivers support automatic configuration (e.g. PNP or PCI) in addition
    > to manually coded parameters.
    >
    > This patch annotates the 104-QUAD-8 driver.
    >
    > Cc: Syed Nayyar Waris <syednwaris@gmail.com>
    > Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
    > ---
    > drivers/counter/104-quad-8.c | 2 +-
    > 1 file changed, 1 insertion(+), 1 deletion(-)
    >
    > diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
    > index 233a3acc1377..0fd61cc82d30 100644
    > --- a/drivers/counter/104-quad-8.c
    > +++ b/drivers/counter/104-quad-8.c
    > @@ -21,7 +21,7 @@
    >
    > static unsigned int base[max_num_isa_dev(QUAD8_EXTENT)];
    > static unsigned int num_quad8;
    > -module_param_array(base, uint, &num_quad8, 0);
    > +module_param_hw_array(base, uint, ioport, &num_quad8, 0);
    > MODULE_PARM_DESC(base, "ACCES 104-QUAD-8 base addresses");
    >
    > #define QUAD8_NUM_COUNTERS 8
    > --
    > 2.30.2
    >

    Acked-by: Syed Nayyar Waris <syednwaris@gmail.com>

    \
     
     \ /
      Last update: 2021-04-15 17:19    [W:4.054 / U:0.464 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site