| Message ID | 148059564995.31612.9567297542032305179.stgit@warthog.procyon.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 12/01/2016 04:34 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/watchdog/. > > Suggested-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> > Signed-off-by: David Howells <dhowells@redhat.com> > cc: Wim Van Sebroeck <wim@iguana.be> > cc: Zwane Mwaikambo <zwanem@gmail.com> > cc: linux-watchdog@vger.kernel.org Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > > drivers/watchdog/cpu5wdt.c | 2 +- > drivers/watchdog/eurotechwdt.c | 4 ++-- > drivers/watchdog/pc87413_wdt.c | 2 +- > drivers/watchdog/sc1200wdt.c | 2 +- > drivers/watchdog/wdt.c | 4 ++-- > 5 files changed, 7 insertions(+), 7 deletions(-) > > diff --git a/drivers/watchdog/cpu5wdt.c b/drivers/watchdog/cpu5wdt.c > index 6d03e8e30f8b..6c3f78e45c26 100644 > --- a/drivers/watchdog/cpu5wdt.c > +++ b/drivers/watchdog/cpu5wdt.c > @@ -289,7 +289,7 @@ MODULE_DESCRIPTION("sma cpu5 watchdog driver"); > MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog"); > MODULE_LICENSE("GPL"); > > -module_param(port, int, 0); > +module_param_hw(port, int, ioport, 0); > MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91"); > > module_param(verbose, int, 0); > diff --git a/drivers/watchdog/eurotechwdt.c b/drivers/watchdog/eurotechwdt.c > index 23ee53240c4c..38e96712264f 100644 > --- a/drivers/watchdog/eurotechwdt.c > +++ b/drivers/watchdog/eurotechwdt.c > @@ -97,9 +97,9 @@ MODULE_PARM_DESC(nowayout, > #define WDT_TIMER_CFG 0xf3 > > > -module_param(io, int, 0); > +module_param_hw(io, int, ioport, 0); > MODULE_PARM_DESC(io, "Eurotech WDT io port (default=0x3f0)"); > -module_param(irq, int, 0); > +module_param_hw(irq, int, irq, 0); > MODULE_PARM_DESC(irq, "Eurotech WDT irq (default=10)"); > module_param(ev, charp, 0); > MODULE_PARM_DESC(ev, "Eurotech WDT event type (default is `int')"); > diff --git a/drivers/watchdog/pc87413_wdt.c b/drivers/watchdog/pc87413_wdt.c > index 9f15dd9435d1..06a892e36a8d 100644 > --- a/drivers/watchdog/pc87413_wdt.c > +++ b/drivers/watchdog/pc87413_wdt.c > @@ -579,7 +579,7 @@ MODULE_AUTHOR("Marcus Junker <junker@anduras.de>"); > MODULE_DESCRIPTION("PC87413 WDT driver"); > MODULE_LICENSE("GPL"); > > -module_param(io, int, 0); > +module_param_hw(io, int, ioport, 0); > MODULE_PARM_DESC(io, MODNAME " I/O port (default: " > __MODULE_STRING(IO_DEFAULT) ")."); > > diff --git a/drivers/watchdog/sc1200wdt.c b/drivers/watchdog/sc1200wdt.c > index 131193a7acdf..b34d3d5ba632 100644 > --- a/drivers/watchdog/sc1200wdt.c > +++ b/drivers/watchdog/sc1200wdt.c > @@ -88,7 +88,7 @@ MODULE_PARM_DESC(isapnp, > "When set to 0 driver ISA PnP support will be disabled"); > #endif > > -module_param(io, int, 0); > +module_param_hw(io, int, ioport, 0); > MODULE_PARM_DESC(io, "io port"); > module_param(timeout, int, 0); > MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1"); > diff --git a/drivers/watchdog/wdt.c b/drivers/watchdog/wdt.c > index e0206b5b7d89..e481fbbc4ae7 100644 > --- a/drivers/watchdog/wdt.c > +++ b/drivers/watchdog/wdt.c > @@ -78,9 +78,9 @@ static int irq = 11; > > static DEFINE_SPINLOCK(wdt_lock); > > -module_param(io, int, 0); > +module_param_hw(io, int, ioport, 0); > MODULE_PARM_DESC(io, "WDT io port (default=0x240)"); > -module_param(irq, int, 0); > +module_param_hw(irq, int, irq, 0); > MODULE_PARM_DESC(irq, "WDT irq (default=11)"); > > /* Support for the Fan Tachometer on the WDT501-P */ > > -- > To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/watchdog/cpu5wdt.c b/drivers/watchdog/cpu5wdt.c index 6d03e8e30f8b..6c3f78e45c26 100644 --- a/drivers/watchdog/cpu5wdt.c +++ b/drivers/watchdog/cpu5wdt.c @@ -289,7 +289,7 @@ MODULE_DESCRIPTION("sma cpu5 watchdog driver"); MODULE_SUPPORTED_DEVICE("sma cpu5 watchdog"); MODULE_LICENSE("GPL"); -module_param(port, int, 0); +module_param_hw(port, int, ioport, 0); MODULE_PARM_DESC(port, "base address of watchdog card, default is 0x91"); module_param(verbose, int, 0); diff --git a/drivers/watchdog/eurotechwdt.c b/drivers/watchdog/eurotechwdt.c index 23ee53240c4c..38e96712264f 100644 --- a/drivers/watchdog/eurotechwdt.c +++ b/drivers/watchdog/eurotechwdt.c @@ -97,9 +97,9 @@ MODULE_PARM_DESC(nowayout, #define WDT_TIMER_CFG 0xf3 -module_param(io, int, 0); +module_param_hw(io, int, ioport, 0); MODULE_PARM_DESC(io, "Eurotech WDT io port (default=0x3f0)"); -module_param(irq, int, 0); +module_param_hw(irq, int, irq, 0); MODULE_PARM_DESC(irq, "Eurotech WDT irq (default=10)"); module_param(ev, charp, 0); MODULE_PARM_DESC(ev, "Eurotech WDT event type (default is `int')"); diff --git a/drivers/watchdog/pc87413_wdt.c b/drivers/watchdog/pc87413_wdt.c index 9f15dd9435d1..06a892e36a8d 100644 --- a/drivers/watchdog/pc87413_wdt.c +++ b/drivers/watchdog/pc87413_wdt.c @@ -579,7 +579,7 @@ MODULE_AUTHOR("Marcus Junker <junker@anduras.de>"); MODULE_DESCRIPTION("PC87413 WDT driver"); MODULE_LICENSE("GPL"); -module_param(io, int, 0); +module_param_hw(io, int, ioport, 0); MODULE_PARM_DESC(io, MODNAME " I/O port (default: " __MODULE_STRING(IO_DEFAULT) ")."); diff --git a/drivers/watchdog/sc1200wdt.c b/drivers/watchdog/sc1200wdt.c index 131193a7acdf..b34d3d5ba632 100644 --- a/drivers/watchdog/sc1200wdt.c +++ b/drivers/watchdog/sc1200wdt.c @@ -88,7 +88,7 @@ MODULE_PARM_DESC(isapnp, "When set to 0 driver ISA PnP support will be disabled"); #endif -module_param(io, int, 0); +module_param_hw(io, int, ioport, 0); MODULE_PARM_DESC(io, "io port"); module_param(timeout, int, 0); MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1"); diff --git a/drivers/watchdog/wdt.c b/drivers/watchdog/wdt.c index e0206b5b7d89..e481fbbc4ae7 100644 --- a/drivers/watchdog/wdt.c +++ b/drivers/watchdog/wdt.c @@ -78,9 +78,9 @@ static int irq = 11; static DEFINE_SPINLOCK(wdt_lock); -module_param(io, int, 0); +module_param_hw(io, int, ioport, 0); MODULE_PARM_DESC(io, "WDT io port (default=0x240)"); -module_param(irq, int, 0); +module_param_hw(irq, int, irq, 0); MODULE_PARM_DESC(irq, "WDT irq (default=11)"); /* Support for the Fan Tachometer on the WDT501-P */
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/watchdog/. Suggested-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> cc: Wim Van Sebroeck <wim@iguana.be> cc: Zwane Mwaikambo <zwanem@gmail.com> cc: linux-watchdog@vger.kernel.org --- drivers/watchdog/cpu5wdt.c | 2 +- drivers/watchdog/eurotechwdt.c | 4 ++-- drivers/watchdog/pc87413_wdt.c | 2 +- drivers/watchdog/sc1200wdt.c | 2 +- drivers/watchdog/wdt.c | 4 ++-- 5 files changed, 7 insertions(+), 7 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html