diff mbox

[03/39] Annotate hardware config module parameters in drivers/char/ipmi/

Message ID 148059540295.31612.4139752007431784342.stgit@warthog.procyon.org.uk
State New
Headers show

Commit Message

David Howells Dec. 1, 2016, 12:30 p.m. UTC
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/char/ipmi/.

Suggested-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Corey Minyard <minyard@acm.org>
cc: openipmi-developer@lists.sourceforge.net
---

 drivers/char/ipmi/ipmi_si_intf.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)


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Comments

Corey Minyard Dec. 1, 2016, 1:14 p.m. UTC | #1
On 12/01/2016 06:30 AM, David Howells 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/char/ipmi/.
>
> Suggested-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Corey Minyard <minyard@acm.org>
> cc: openipmi-developer@lists.sourceforge.net

Reviewed by: Corey Minyard <cminyard@mvista.com>

> ---
>
>   drivers/char/ipmi/ipmi_si_intf.c |   14 +++++++-------
>   1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
> index a112c0146012..157e96391eca 100644
> --- a/drivers/char/ipmi/ipmi_si_intf.c
> +++ b/drivers/char/ipmi/ipmi_si_intf.c
> @@ -1375,39 +1375,39 @@ MODULE_PARM_DESC(type, "Defines the type of each interface, each"
>   		 " interface separated by commas.  The types are 'kcs',"
>   		 " 'smic', and 'bt'.  For example si_type=kcs,bt will set"
>   		 " the first interface to kcs and the second to bt");
> -module_param_array(addrs, ulong, &num_addrs, 0);
> +module_param_hw_array(addrs, ulong, iomem, &num_addrs, 0);
>   MODULE_PARM_DESC(addrs, "Sets the memory address of each interface, the"
>   		 " addresses separated by commas.  Only use if an interface"
>   		 " is in memory.  Otherwise, set it to zero or leave"
>   		 " it blank.");
> -module_param_array(ports, uint, &num_ports, 0);
> +module_param_hw_array(ports, uint, ioport, &num_ports, 0);
>   MODULE_PARM_DESC(ports, "Sets the port address of each interface, the"
>   		 " addresses separated by commas.  Only use if an interface"
>   		 " is a port.  Otherwise, set it to zero or leave"
>   		 " it blank.");
> -module_param_array(irqs, int, &num_irqs, 0);
> +module_param_hw_array(irqs, int, irq, &num_irqs, 0);
>   MODULE_PARM_DESC(irqs, "Sets the interrupt of each interface, the"
>   		 " addresses separated by commas.  Only use if an interface"
>   		 " has an interrupt.  Otherwise, set it to zero or leave"
>   		 " it blank.");
> -module_param_array(regspacings, int, &num_regspacings, 0);
> +module_param_hw_array(regspacings, int, other, &num_regspacings, 0);
>   MODULE_PARM_DESC(regspacings, "The number of bytes between the start address"
>   		 " and each successive register used by the interface.  For"
>   		 " instance, if the start address is 0xca2 and the spacing"
>   		 " is 2, then the second address is at 0xca4.  Defaults"
>   		 " to 1.");
> -module_param_array(regsizes, int, &num_regsizes, 0);
> +module_param_hw_array(regsizes, int, other, &num_regsizes, 0);
>   MODULE_PARM_DESC(regsizes, "The size of the specific IPMI register in bytes."
>   		 " This should generally be 1, 2, 4, or 8 for an 8-bit,"
>   		 " 16-bit, 32-bit, or 64-bit register.  Use this if you"
>   		 " the 8-bit IPMI register has to be read from a larger"
>   		 " register.");
> -module_param_array(regshifts, int, &num_regshifts, 0);
> +module_param_hw_array(regshifts, int, other, &num_regshifts, 0);
>   MODULE_PARM_DESC(regshifts, "The amount to shift the data read from the."
>   		 " IPMI register, in bits.  For instance, if the data"
>   		 " is read from a 32-bit word and the IPMI data is in"
>   		 " bit 8-15, then the shift would be 8");
> -module_param_array(slave_addrs, int, &num_slave_addrs, 0);
> +module_param_hw_array(slave_addrs, int, other, &num_slave_addrs, 0);
>   MODULE_PARM_DESC(slave_addrs, "Set the default IPMB slave address for"
>   		 " the controller.  Normally this is 0x20, but can be"
>   		 " overridden by this parm.  This is an array indexed"
>

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diff mbox

Patch

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index a112c0146012..157e96391eca 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -1375,39 +1375,39 @@  MODULE_PARM_DESC(type, "Defines the type of each interface, each"
 		 " interface separated by commas.  The types are 'kcs',"
 		 " 'smic', and 'bt'.  For example si_type=kcs,bt will set"
 		 " the first interface to kcs and the second to bt");
-module_param_array(addrs, ulong, &num_addrs, 0);
+module_param_hw_array(addrs, ulong, iomem, &num_addrs, 0);
 MODULE_PARM_DESC(addrs, "Sets the memory address of each interface, the"
 		 " addresses separated by commas.  Only use if an interface"
 		 " is in memory.  Otherwise, set it to zero or leave"
 		 " it blank.");
-module_param_array(ports, uint, &num_ports, 0);
+module_param_hw_array(ports, uint, ioport, &num_ports, 0);
 MODULE_PARM_DESC(ports, "Sets the port address of each interface, the"
 		 " addresses separated by commas.  Only use if an interface"
 		 " is a port.  Otherwise, set it to zero or leave"
 		 " it blank.");
-module_param_array(irqs, int, &num_irqs, 0);
+module_param_hw_array(irqs, int, irq, &num_irqs, 0);
 MODULE_PARM_DESC(irqs, "Sets the interrupt of each interface, the"
 		 " addresses separated by commas.  Only use if an interface"
 		 " has an interrupt.  Otherwise, set it to zero or leave"
 		 " it blank.");
-module_param_array(regspacings, int, &num_regspacings, 0);
+module_param_hw_array(regspacings, int, other, &num_regspacings, 0);
 MODULE_PARM_DESC(regspacings, "The number of bytes between the start address"
 		 " and each successive register used by the interface.  For"
 		 " instance, if the start address is 0xca2 and the spacing"
 		 " is 2, then the second address is at 0xca4.  Defaults"
 		 " to 1.");
-module_param_array(regsizes, int, &num_regsizes, 0);
+module_param_hw_array(regsizes, int, other, &num_regsizes, 0);
 MODULE_PARM_DESC(regsizes, "The size of the specific IPMI register in bytes."
 		 " This should generally be 1, 2, 4, or 8 for an 8-bit,"
 		 " 16-bit, 32-bit, or 64-bit register.  Use this if you"
 		 " the 8-bit IPMI register has to be read from a larger"
 		 " register.");
-module_param_array(regshifts, int, &num_regshifts, 0);
+module_param_hw_array(regshifts, int, other, &num_regshifts, 0);
 MODULE_PARM_DESC(regshifts, "The amount to shift the data read from the."
 		 " IPMI register, in bits.  For instance, if the data"
 		 " is read from a 32-bit word and the IPMI data is in"
 		 " bit 8-15, then the shift would be 8");
-module_param_array(slave_addrs, int, &num_slave_addrs, 0);
+module_param_hw_array(slave_addrs, int, other, &num_slave_addrs, 0);
 MODULE_PARM_DESC(slave_addrs, "Set the default IPMB slave address for"
 		 " the controller.  Normally this is 0x20, but can be"
 		 " overridden by this parm.  This is an array indexed"