50 lines
2.2 KiB
Diff
50 lines
2.2 KiB
Diff
From: David Howells <dhowells@redhat.com>
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Date: Tue, 4 Apr 2017 16:54:22 +0100
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Subject: [05/62] Annotate hardware config module parameters in drivers/char/
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Origin: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit?id=3a5a43a8e71e6c0f03ba07d7125faccc8c851d65
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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/char/.
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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/char/applicom.c | 4 ++--
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1 file changed, 2 insertions(+), 2 deletions(-)
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diff --git a/drivers/char/applicom.c b/drivers/char/applicom.c
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index e770ad977472..b67263d6e34b 100644
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--- a/drivers/char/applicom.c
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+++ b/drivers/char/applicom.c
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@@ -94,9 +94,9 @@ static struct applicom_board {
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static unsigned int irq = 0; /* interrupt number IRQ */
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static unsigned long mem = 0; /* physical segment of board */
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-module_param(irq, uint, 0);
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+module_param_hw(irq, uint, irq, 0);
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MODULE_PARM_DESC(irq, "IRQ of the Applicom board");
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-module_param(mem, ulong, 0);
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+module_param_hw(mem, ulong, iomem, 0);
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MODULE_PARM_DESC(mem, "Shared Memory Address of Applicom board");
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static unsigned int numboards; /* number of installed boards */
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