[08/38] Annotate hardware config module parameters in drivers/gpio/

Submitted by David Howells on April 5, 2017, 4:57 p.m.

Details

Message ID 149141147489.29162.566616944109123278.stgit@warthog.procyon.org.uk
State New
Headers show

Commit Message

David Howells April 5, 2017, 4:57 p.m.
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/gpio/.

Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
cc: Alexandre Courbot <gnurou@gmail.com>
cc: linux-gpio@vger.kernel.org
---

 drivers/gpio/gpio-104-dio-48e.c |    4 ++--
 drivers/gpio/gpio-104-idi-48.c  |    4 ++--
 drivers/gpio/gpio-104-idio-16.c |    4 ++--
 drivers/gpio/gpio-gpio-mm.c     |    2 +-
 drivers/gpio/gpio-ws16c48.c     |    4 ++--
 5 files changed, 9 insertions(+), 9 deletions(-)


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Comments

Linus Walleij April 7, 2017, 10:42 a.m.
On Wed, Apr 5, 2017 at 6:57 PM, David Howells <dhowells@redhat.com> 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 drivers in drivers/gpio/.
>
> Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
> Signed-off-by: David Howells <dhowells@redhat.com>
> Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
> Acked-by: Linus Walleij <linus.walleij@linaro.org>
> cc: Alexandre Courbot <gnurou@gmail.com>
> cc: linux-gpio@vger.kernel.org

Acked-by: Linus Walleij <linus.walleij@linaro.org>

I see that I don't have this symbol in my tree so I guess the patch
series adds it and this patch needs to follow it.

Yours,
Linus Walleij
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David Howells April 7, 2017, 12:52 p.m.
Linus Walleij <linus.walleij@linaro.org> wrote:

> I see that I don't have this symbol in my tree so I guess the patch
> series adds it and this patch needs to follow it.

Yep.  Patch #1 adds it.

David
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Patch hide | download patch | download mbox

diff --git a/drivers/gpio/gpio-104-dio-48e.c b/drivers/gpio/gpio-104-dio-48e.c
index 17bd2ab4ebe2..dfa1a298e4f6 100644
--- a/drivers/gpio/gpio-104-dio-48e.c
+++ b/drivers/gpio/gpio-104-dio-48e.c
@@ -33,11 +33,11 @@ 
 
 static unsigned int base[MAX_NUM_DIO48E];
 static unsigned int num_dio48e;
-module_param_array(base, uint, &num_dio48e, 0);
+module_param_hw_array(base, uint, ioport, &num_dio48e, 0);
 MODULE_PARM_DESC(base, "ACCES 104-DIO-48E base addresses");
 
 static unsigned int irq[MAX_NUM_DIO48E];
-module_param_array(irq, uint, NULL, 0);
+module_param_hw_array(irq, uint, irq, NULL, 0);
 MODULE_PARM_DESC(irq, "ACCES 104-DIO-48E interrupt line numbers");
 
 /**
diff --git a/drivers/gpio/gpio-104-idi-48.c b/drivers/gpio/gpio-104-idi-48.c
index 568375a7ebc2..c369b2083876 100644
--- a/drivers/gpio/gpio-104-idi-48.c
+++ b/drivers/gpio/gpio-104-idi-48.c
@@ -33,11 +33,11 @@ 
 
 static unsigned int base[MAX_NUM_IDI_48];
 static unsigned int num_idi_48;
-module_param_array(base, uint, &num_idi_48, 0);
+module_param_hw_array(base, uint, ioport, &num_idi_48, 0);
 MODULE_PARM_DESC(base, "ACCES 104-IDI-48 base addresses");
 
 static unsigned int irq[MAX_NUM_IDI_48];
-module_param_array(irq, uint, NULL, 0);
+module_param_hw_array(irq, uint, irq, NULL, 0);
 MODULE_PARM_DESC(irq, "ACCES 104-IDI-48 interrupt line numbers");
 
 /**
diff --git a/drivers/gpio/gpio-104-idio-16.c b/drivers/gpio/gpio-104-idio-16.c
index 7053cf736648..5949123986f2 100644
--- a/drivers/gpio/gpio-104-idio-16.c
+++ b/drivers/gpio/gpio-104-idio-16.c
@@ -33,11 +33,11 @@ 
 
 static unsigned int base[MAX_NUM_IDIO_16];
 static unsigned int num_idio_16;
-module_param_array(base, uint, &num_idio_16, 0);
+module_param_hw_array(base, uint, ioport, &num_idio_16, 0);
 MODULE_PARM_DESC(base, "ACCES 104-IDIO-16 base addresses");
 
 static unsigned int irq[MAX_NUM_IDIO_16];
-module_param_array(irq, uint, NULL, 0);
+module_param_hw_array(irq, uint, irq, NULL, 0);
 MODULE_PARM_DESC(irq, "ACCES 104-IDIO-16 interrupt line numbers");
 
 /**
diff --git a/drivers/gpio/gpio-gpio-mm.c b/drivers/gpio/gpio-gpio-mm.c
index fa4baa2543db..11ade5b288f8 100644
--- a/drivers/gpio/gpio-gpio-mm.c
+++ b/drivers/gpio/gpio-gpio-mm.c
@@ -31,7 +31,7 @@ 
 
 static unsigned int base[MAX_NUM_GPIOMM];
 static unsigned int num_gpiomm;
-module_param_array(base, uint, &num_gpiomm, 0);
+module_param_hw_array(base, uint, ioport, &num_gpiomm, 0);
 MODULE_PARM_DESC(base, "Diamond Systems GPIO-MM base addresses");
 
 /**
diff --git a/drivers/gpio/gpio-ws16c48.c b/drivers/gpio/gpio-ws16c48.c
index 901b5ccb032d..f8a4f91f36c7 100644
--- a/drivers/gpio/gpio-ws16c48.c
+++ b/drivers/gpio/gpio-ws16c48.c
@@ -30,11 +30,11 @@ 
 
 static unsigned int base[MAX_NUM_WS16C48];
 static unsigned int num_ws16c48;
-module_param_array(base, uint, &num_ws16c48, 0);
+module_param_hw_array(base, uint, ioport, &num_ws16c48, 0);
 MODULE_PARM_DESC(base, "WinSystems WS16C48 base addresses");
 
 static unsigned int irq[MAX_NUM_WS16C48];
-module_param_array(irq, uint, NULL, 0);
+module_param_hw_array(irq, uint, irq, NULL, 0);
 MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers");
 
 /**