[PATCH 31/38] Annotate hardware config module parameters in drivers/tty/

David Howells dhowells at redhat.com
Wed Apr 5 17:01:26 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/tty/.

Suggested-by: Alan Cox <gnomes at lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells at redhat.com>
cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
cc: Jiri Slaby <jslaby at suse.com>
cc: linux-serial at vger.kernel.org
---

 drivers/tty/cyclades.c              |    4 ++--
 drivers/tty/moxa.c                  |    2 +-
 drivers/tty/mxser.c                 |    2 +-
 drivers/tty/rocket.c                |   10 +++++-----
 drivers/tty/serial/8250/8250_core.c |    4 ++--
 drivers/tty/synclink.c              |    6 +++---
 6 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/tty/cyclades.c b/drivers/tty/cyclades.c
index 5e4fa9206861..104f09c58163 100644
--- a/drivers/tty/cyclades.c
+++ b/drivers/tty/cyclades.c
@@ -156,8 +156,8 @@ static unsigned int cy_isa_addresses[] = {
 static long maddr[NR_CARDS];
 static int irq[NR_CARDS];
 
-module_param_array(maddr, long, NULL, 0);
-module_param_array(irq, int, NULL, 0);
+module_param_hw_array(maddr, long, iomem, NULL, 0);
+module_param_hw_array(irq, int, irq, NULL, 0);
 
 #endif				/* CONFIG_ISA */
 
diff --git a/drivers/tty/moxa.c b/drivers/tty/moxa.c
index 4caf0c3b1f99..3b251f4e5df0 100644
--- a/drivers/tty/moxa.c
+++ b/drivers/tty/moxa.c
@@ -179,7 +179,7 @@ MODULE_FIRMWARE("c320tunx.cod");
 
 module_param_array(type, uint, NULL, 0);
 MODULE_PARM_DESC(type, "card type: C218=2, C320=4");
-module_param_array(baseaddr, ulong, NULL, 0);
+module_param_hw_array(baseaddr, ulong, ioport, NULL, 0);
 MODULE_PARM_DESC(baseaddr, "base address");
 module_param_array(numports, uint, NULL, 0);
 MODULE_PARM_DESC(numports, "numports (ignored for C218)");
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 7b8f383fb090..8bd6fb6d9391 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -183,7 +183,7 @@ static int ttymajor = MXSERMAJOR;
 
 MODULE_AUTHOR("Casper Yang");
 MODULE_DESCRIPTION("MOXA Smartio/Industio Family Multiport Board Device Driver");
-module_param_array(ioaddr, ulong, NULL, 0);
+module_param_hw_array(ioaddr, ulong, ioport, NULL, 0);
 MODULE_PARM_DESC(ioaddr, "ISA io addresses to look for a moxa board");
 module_param(ttymajor, int, 0);
 MODULE_LICENSE("GPL");
diff --git a/drivers/tty/rocket.c b/drivers/tty/rocket.c
index d66c1edd9892..b51a877da986 100644
--- a/drivers/tty/rocket.c
+++ b/drivers/tty/rocket.c
@@ -250,15 +250,15 @@ static int sReadAiopNumChan(WordIO_t io);
 
 MODULE_AUTHOR("Theodore Ts'o");
 MODULE_DESCRIPTION("Comtrol RocketPort driver");
-module_param(board1, ulong, 0);
+module_param_hw(board1, ulong, ioport, 0);
 MODULE_PARM_DESC(board1, "I/O port for (ISA) board #1");
-module_param(board2, ulong, 0);
+module_param_hw(board2, ulong, ioport, 0);
 MODULE_PARM_DESC(board2, "I/O port for (ISA) board #2");
-module_param(board3, ulong, 0);
+module_param_hw(board3, ulong, ioport, 0);
 MODULE_PARM_DESC(board3, "I/O port for (ISA) board #3");
-module_param(board4, ulong, 0);
+module_param_hw(board4, ulong, ioport, 0);
 MODULE_PARM_DESC(board4, "I/O port for (ISA) board #4");
-module_param(controller, ulong, 0);
+module_param_hw(controller, ulong, ioport, 0);
 MODULE_PARM_DESC(controller, "I/O port for (ISA) rocketport controller");
 module_param(support_low_speed, bool, 0);
 MODULE_PARM_DESC(support_low_speed, "1 means support 50 baud, 0 means support 460400 baud");
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 76e03a7de9cc..89fde17d9617 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1191,7 +1191,7 @@ module_exit(serial8250_exit);
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Generic 8250/16x50 serial driver");
 
-module_param(share_irqs, uint, 0644);
+module_param_hw(share_irqs, uint, other, 0644);
 MODULE_PARM_DESC(share_irqs, "Share IRQs with other non-8250/16x50 devices (unsafe)");
 
 module_param(nr_uarts, uint, 0644);
@@ -1201,7 +1201,7 @@ module_param(skip_txen_test, uint, 0644);
 MODULE_PARM_DESC(skip_txen_test, "Skip checking for the TXEN bug at init time");
 
 #ifdef CONFIG_SERIAL_8250_RSA
-module_param_array(probe_rsa, ulong, &probe_rsa_count, 0444);
+module_param_hw_array(probe_rsa, ulong, ioport, &probe_rsa_count, 0444);
 MODULE_PARM_DESC(probe_rsa, "Probe I/O ports for RSA");
 #endif
 MODULE_ALIAS_CHARDEV_MAJOR(TTY_MAJOR);
diff --git a/drivers/tty/synclink.c b/drivers/tty/synclink.c
index 657eed82eeb3..a2c308f7d637 100644
--- a/drivers/tty/synclink.c
+++ b/drivers/tty/synclink.c
@@ -869,9 +869,9 @@ static int txholdbufs[MAX_TOTAL_DEVICES];
 	
 module_param(break_on_load, bool, 0);
 module_param(ttymajor, int, 0);
-module_param_array(io, int, NULL, 0);
-module_param_array(irq, int, NULL, 0);
-module_param_array(dma, int, NULL, 0);
+module_param_hw_array(io, int, ioport, NULL, 0);
+module_param_hw_array(irq, int, irq, NULL, 0);
+module_param_hw_array(dma, int, dma, NULL, 0);
 module_param(debug_level, int, 0);
 module_param_array(maxframe, int, NULL, 0);
 module_param_array(txdmabufs, int, NULL, 0);

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