[PATCH 23/38] Annotate hardware config module parameters in drivers/net/wireless/

David Howells dhowells at redhat.com
Wed Apr 5 17:00:21 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/net/wireless/.

Suggested-by: Alan Cox <gnomes at lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells at redhat.com>
cc: Kalle Valo <kvalo at codeaurora.org>
cc: linux-wireless at vger.kernel.org
cc: netdev at vger.kernel.org
---

 drivers/net/wireless/cisco/airo.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/cisco/airo.c b/drivers/net/wireless/cisco/airo.c
index 4b040451a9b8..1b7e125a28e2 100644
--- a/drivers/net/wireless/cisco/airo.c
+++ b/drivers/net/wireless/cisco/airo.c
@@ -246,8 +246,8 @@ MODULE_DESCRIPTION("Support for Cisco/Aironet 802.11 wireless ethernet cards.  "
 		   "Direct support for ISA/PCI/MPI cards and support for PCMCIA when used with airo_cs.");
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_SUPPORTED_DEVICE("Aironet 4500, 4800 and Cisco 340/350");
-module_param_array(io, int, NULL, 0);
-module_param_array(irq, int, NULL, 0);
+module_param_hw_array(io, int, ioport, NULL, 0);
+module_param_hw_array(irq, int, irq, NULL, 0);
 module_param_array(rates, int, NULL, 0);
 module_param_array(ssids, charp, NULL, 0);
 module_param(auto_wep, int, 0);

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