Revision c66650d29764e228eba40b7a59fdb70fa6567daa authored by Kees Cook on 22 September 2023, 17:53:19 UTC, committed by Dan Williams on 22 September 2023, 21:31:04 UTC
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct cxl_cxims_data.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-cxl@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230922175319.work.096-kees@kernel.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
1 parent a76b625
Raw File
drm_module.h
/* SPDX-License-Identifier: MIT */

#ifndef DRM_MODULE_H
#define DRM_MODULE_H

#include <linux/pci.h>
#include <linux/platform_device.h>

#include <drm/drm_drv.h>

/**
 * DOC: overview
 *
 * This library provides helpers registering DRM drivers during module
 * initialization and shutdown. The provided helpers act like bus-specific
 * module helpers, such as module_pci_driver(), but respect additional
 * parameters that control DRM driver registration.
 *
 * Below is an example of initializing a DRM driver for a device on the
 * PCI bus.
 *
 * .. code-block:: c
 *
 *	struct pci_driver my_pci_drv = {
 *	};
 *
 *	drm_module_pci_driver(my_pci_drv);
 *
 * The generated code will test if DRM drivers are enabled and register
 * the PCI driver my_pci_drv. For more complex module initialization, you
 * can still use module_init() and module_exit() in your driver.
 */

/*
 * PCI drivers
 */

static inline int __init drm_pci_register_driver(struct pci_driver *pci_drv)
{
	if (drm_firmware_drivers_only())
		return -ENODEV;

	return pci_register_driver(pci_drv);
}

/**
 * drm_module_pci_driver - Register a DRM driver for PCI-based devices
 * @__pci_drv: the PCI driver structure
 *
 * Registers a DRM driver for devices on the PCI bus. The helper
 * macro behaves like module_pci_driver() but tests the state of
 * drm_firmware_drivers_only(). For more complex module initialization,
 * use module_init() and module_exit() directly.
 *
 * Each module may only use this macro once. Calling it replaces
 * module_init() and module_exit().
 */
#define drm_module_pci_driver(__pci_drv) \
	module_driver(__pci_drv, drm_pci_register_driver, pci_unregister_driver)

static inline int __init
drm_pci_register_driver_if_modeset(struct pci_driver *pci_drv, int modeset)
{
	if (drm_firmware_drivers_only() && modeset == -1)
		return -ENODEV;
	if (modeset == 0)
		return -ENODEV;

	return pci_register_driver(pci_drv);
}

static inline void __exit
drm_pci_unregister_driver_if_modeset(struct pci_driver *pci_drv, int modeset)
{
	pci_unregister_driver(pci_drv);
}

/**
 * drm_module_pci_driver_if_modeset - Register a DRM driver for PCI-based devices
 * @__pci_drv: the PCI driver structure
 * @__modeset: an additional parameter that disables the driver
 *
 * This macro is deprecated and only provided for existing drivers. For
 * new drivers, use drm_module_pci_driver().
 *
 * Registers a DRM driver for devices on the PCI bus. The helper macro
 * behaves like drm_module_pci_driver() with an additional driver-specific
 * flag. If __modeset is 0, the driver has been disabled, if __modeset is
 * -1 the driver state depends on the global DRM state. For all other
 * values, the PCI driver has been enabled. The default should be -1.
 */
#define drm_module_pci_driver_if_modeset(__pci_drv, __modeset) \
	module_driver(__pci_drv, drm_pci_register_driver_if_modeset, \
		      drm_pci_unregister_driver_if_modeset, __modeset)

/*
 * Platform drivers
 */

static inline int __init
drm_platform_driver_register(struct platform_driver *platform_drv)
{
	if (drm_firmware_drivers_only())
		return -ENODEV;

	return platform_driver_register(platform_drv);
}

/**
 * drm_module_platform_driver - Register a DRM driver for platform devices
 * @__platform_drv: the platform driver structure
 *
 * Registers a DRM driver for devices on the platform bus. The helper
 * macro behaves like module_platform_driver() but tests the state of
 * drm_firmware_drivers_only(). For more complex module initialization,
 * use module_init() and module_exit() directly.
 *
 * Each module may only use this macro once. Calling it replaces
 * module_init() and module_exit().
 */
#define drm_module_platform_driver(__platform_drv) \
	module_driver(__platform_drv, drm_platform_driver_register, \
		      platform_driver_unregister)

#endif
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