[PATCH 09/38] Annotate hardware config module parameters in drivers/i2c/

From: David Howells
Date: Wed Apr 05 2017 - 13:00:52 EST


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/i2c/.

Suggested-by: Alan Cox <gnomes@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Wolfram Sang <wsa@xxxxxxxxxxxxx>
cc: Jean Delvare <jdelvare@xxxxxxxx>
cc: linux-i2c@xxxxxxxxxxxxxxx
---

drivers/i2c/busses/i2c-ali15x3.c | 2 +-
drivers/i2c/busses/i2c-elektor.c | 6 +++---
drivers/i2c/busses/i2c-parport-light.c | 4 ++--
drivers/i2c/busses/i2c-pca-isa.c | 4 ++--
drivers/i2c/busses/i2c-piix4.c | 2 +-
drivers/i2c/busses/i2c-sis5595.c | 2 +-
drivers/i2c/busses/i2c-viapro.c | 2 +-
drivers/i2c/busses/scx200_acb.c | 2 +-
8 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/busses/i2c-ali15x3.c b/drivers/i2c/busses/i2c-ali15x3.c
index 45c5c4883022..6e6bf46bcb52 100644
--- a/drivers/i2c/busses/i2c-ali15x3.c
+++ b/drivers/i2c/busses/i2c-ali15x3.c
@@ -119,7 +119,7 @@
/* If force_addr is set to anything different from 0, we forcibly enable
the device at the given address. */
static u16 force_addr;
-module_param(force_addr, ushort, 0);
+module_param_hw(force_addr, ushort, ioport, 0);
MODULE_PARM_DESC(force_addr,
"Initialize the base address of the i2c controller");

diff --git a/drivers/i2c/busses/i2c-elektor.c b/drivers/i2c/busses/i2c-elektor.c
index 8af62fb3fe41..5416003e0605 100644
--- a/drivers/i2c/busses/i2c-elektor.c
+++ b/drivers/i2c/busses/i2c-elektor.c
@@ -323,9 +323,9 @@ MODULE_AUTHOR("Hans Berglund <hb@xxxxxxxxxxx>");
MODULE_DESCRIPTION("I2C-Bus adapter routines for PCF8584 ISA bus adapter");
MODULE_LICENSE("GPL");

-module_param(base, int, 0);
-module_param(irq, int, 0);
+module_param_hw(base, int, ioport_or_iomem, 0);
+module_param_hw(irq, int, irq, 0);
module_param(clock, int, 0);
module_param(own, int, 0);
-module_param(mmapped, int, 0);
+module_param_hw(mmapped, int, other, 0);
module_isa_driver(i2c_elektor_driver, 1);
diff --git a/drivers/i2c/busses/i2c-parport-light.c b/drivers/i2c/busses/i2c-parport-light.c
index 1bcdd10b68b9..faa8fb8f2b8f 100644
--- a/drivers/i2c/busses/i2c-parport-light.c
+++ b/drivers/i2c/busses/i2c-parport-light.c
@@ -38,11 +38,11 @@
static struct platform_device *pdev;

static u16 base;
-module_param(base, ushort, 0);
+module_param_hw(base, ushort, ioport, 0);
MODULE_PARM_DESC(base, "Base I/O address");

static int irq;
-module_param(irq, int, 0);
+module_param_hw(irq, int, irq, 0);
MODULE_PARM_DESC(irq, "IRQ (optional)");

/* ----- Low-level parallel port access ----------------------------------- */
diff --git a/drivers/i2c/busses/i2c-pca-isa.c b/drivers/i2c/busses/i2c-pca-isa.c
index ba88f17f636c..946ac646de2a 100644
--- a/drivers/i2c/busses/i2c-pca-isa.c
+++ b/drivers/i2c/busses/i2c-pca-isa.c
@@ -197,9 +197,9 @@ MODULE_AUTHOR("Ian Campbell <icampbell@xxxxxxxxx>");
MODULE_DESCRIPTION("ISA base PCA9564/PCA9665 driver");
MODULE_LICENSE("GPL");

-module_param(base, ulong, 0);
+module_param_hw(base, ulong, ioport, 0);
MODULE_PARM_DESC(base, "I/O base address");
-module_param(irq, int, 0);
+module_param_hw(irq, int, irq, 0);
MODULE_PARM_DESC(irq, "IRQ");
module_param(clock, int, 0);
MODULE_PARM_DESC(clock, "Clock rate in hertz.\n\t\t"
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index c21ca7bf2efe..0ecdb47a23ab 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -106,7 +106,7 @@ MODULE_PARM_DESC(force, "Forcibly enable the PIIX4. DANGEROUS!");
/* If force_addr is set to anything different from 0, we forcibly enable
the PIIX4 at the given address. VERY DANGEROUS! */
static int force_addr;
-module_param (force_addr, int, 0);
+module_param_hw(force_addr, int, ioport, 0);
MODULE_PARM_DESC(force_addr,
"Forcibly enable the PIIX4 at the given address. "
"EXTREMELY DANGEROUS!");
diff --git a/drivers/i2c/busses/i2c-sis5595.c b/drivers/i2c/busses/i2c-sis5595.c
index 7d58a40faf2d..d543a9867ba4 100644
--- a/drivers/i2c/busses/i2c-sis5595.c
+++ b/drivers/i2c/busses/i2c-sis5595.c
@@ -119,7 +119,7 @@ static int blacklist[] = {
/* If force_addr is set to anything different from 0, we forcibly enable
the device at the given address. */
static u16 force_addr;
-module_param(force_addr, ushort, 0);
+module_param_hw(force_addr, ushort, ioport, 0);
MODULE_PARM_DESC(force_addr, "Initialize the base address of the i2c controller");

static struct pci_driver sis5595_driver;
diff --git a/drivers/i2c/busses/i2c-viapro.c b/drivers/i2c/busses/i2c-viapro.c
index 0ee2646f3b00..0dc45e12bb1d 100644
--- a/drivers/i2c/busses/i2c-viapro.c
+++ b/drivers/i2c/busses/i2c-viapro.c
@@ -94,7 +94,7 @@ MODULE_PARM_DESC(force, "Forcibly enable the SMBus. DANGEROUS!");
/* If force_addr is set to anything different from 0, we forcibly enable
the VT596 at the given address. VERY DANGEROUS! */
static u16 force_addr;
-module_param(force_addr, ushort, 0);
+module_param_hw(force_addr, ushort, ioport, 0);
MODULE_PARM_DESC(force_addr,
"Forcibly enable the SMBus at the given address. "
"EXTREMELY DANGEROUS!");
diff --git a/drivers/i2c/busses/scx200_acb.c b/drivers/i2c/busses/scx200_acb.c
index 0a7e410b6195..e0923bee8d1f 100644
--- a/drivers/i2c/busses/scx200_acb.c
+++ b/drivers/i2c/busses/scx200_acb.c
@@ -42,7 +42,7 @@ MODULE_LICENSE("GPL");

#define MAX_DEVICES 4
static int base[MAX_DEVICES] = { 0x820, 0x840 };
-module_param_array(base, int, NULL, 0);
+module_param_hw_array(base, int, ioport, NULL, 0);
MODULE_PARM_DESC(base, "Base addresses for the ACCESS.bus controllers");

#define POLL_TIMEOUT (HZ/5)