46 lines
2.0 KiB
Diff
46 lines
2.0 KiB
Diff
From: David Howells <dhowells@redhat.com>
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Date: Tue, 4 Apr 2017 16:54:24 +0100
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Subject: [14/62] Annotate hardware config module parameters in drivers/misc/
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Origin: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit?id=78c42a679f4795421aa74c469bbce417f9eed08d
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When the kernel is running in secure boot mode, we lock down the kernel to
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prevent userspace from modifying the running kernel image. Whilst this
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includes prohibiting access to things like /dev/mem, it must also prevent
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access by means of configuring driver modules in such a way as to cause a
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device to access or modify the kernel image.
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To this end, annotate module_param* statements that refer to hardware
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configuration and indicate for future reference what type of parameter they
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specify. The parameter parser in the core sees this information and can
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skip such parameters with an error message if the kernel is locked down.
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The module initialisation then runs as normal, but just sees whatever the
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default values for those parameters is.
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Note that we do still need to do the module initialisation because some
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drivers have viable defaults set in case parameters aren't specified and
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some drivers support automatic configuration (e.g. PNP or PCI) in addition
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to manually coded parameters.
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This patch annotates drivers in drivers/misc/.
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Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
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Signed-off-by: David Howells <dhowells@redhat.com>
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cc: Arnd Bergmann <arnd@arndb.de>
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cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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---
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drivers/misc/dummy-irq.c | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/drivers/misc/dummy-irq.c b/drivers/misc/dummy-irq.c
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index acbbe0390be4..76a1015d5783 100644
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--- a/drivers/misc/dummy-irq.c
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+++ b/drivers/misc/dummy-irq.c
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@@ -59,6 +59,6 @@ module_exit(dummy_irq_exit);
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Jiri Kosina");
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-module_param(irq, uint, 0444);
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+module_param_hw(irq, uint, irq, 0444);
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MODULE_PARM_DESC(irq, "The IRQ to register for");
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MODULE_DESCRIPTION("Dummy IRQ handler driver");
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