[PATCH 30/38] Annotate hardware config module parameters in drivers/staging/vme/

David Howells dhowells at redhat.com
Wed Apr 5 17:01:18 UTC 2017


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 drivers in drivers/staging/vme/.

Suggested-by: Alan Cox <gnomes at lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells at redhat.com>
cc: Martyn Welch <martyn at welchs.me.uk>
cc: Manohar Vanga <manohar.vanga at gmail.com>
cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
cc: devel at driverdev.osuosl.org
---

 drivers/staging/vme/devices/vme_pio2_core.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/vme/devices/vme_pio2_core.c b/drivers/staging/vme/devices/vme_pio2_core.c
index 20a2d835fdaa..367535b4b77f 100644
--- a/drivers/staging/vme/devices/vme_pio2_core.c
+++ b/drivers/staging/vme/devices/vme_pio2_core.c
@@ -466,16 +466,16 @@ static void __exit pio2_exit(void)
 
 /* These are required for each board */
 MODULE_PARM_DESC(bus, "Enumeration of VMEbus to which the board is connected");
-module_param_array(bus, int, &bus_num, 0444);
+module_param_hw_array(bus, int, other, &bus_num, 0444);
 
 MODULE_PARM_DESC(base, "Base VME address for PIO2 Registers");
-module_param_array(base, long, &base_num, 0444);
+module_param_hw_array(base, long, other, &base_num, 0444);
 
 MODULE_PARM_DESC(vector, "VME IRQ Vector (Lower 4 bits masked)");
-module_param_array(vector, int, &vector_num, 0444);
+module_param_hw_array(vector, int, other, &vector_num, 0444);
 
 MODULE_PARM_DESC(level, "VME IRQ Level");
-module_param_array(level, int, &level_num, 0444);
+module_param_hw_array(level, int, other, &level_num, 0444);
 
 MODULE_PARM_DESC(variant, "Last 4 characters of PIO2 board variant");
 module_param_array(variant, charp, &variant_num, 0444);



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