mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-28 11:18:45 +07:00
2b6207291b
There is a comment here which says that DIV_ROUND_UP() and that's where the problem comes from. Say you pick: args->bpp = UINT_MAX - 7; args->width = 4; args->height = 1; The integer overflow in DIV_ROUND_UP() means "cpp" is UINT_MAX / 8 and because of how we picked args->width that means cpp < UINT_MAX / 4. I've fixed it by preventing the integer overflow in DIV_ROUND_UP(). I removed the check for !cpp because it's not possible after this change. I also changed all the 0xffffffffU references to U32_MAX. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20180516140026.GA19340@mwanda
140 lines
4.7 KiB
C
140 lines
4.7 KiB
C
/*
|
|
* Copyright (c) 2006-2008 Intel Corporation
|
|
* Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
|
|
* Copyright (c) 2008 Red Hat Inc.
|
|
* Copyright (c) 2016 Intel Corporation
|
|
*
|
|
* Permission to use, copy, modify, distribute, and sell this software and its
|
|
* documentation for any purpose is hereby granted without fee, provided that
|
|
* the above copyright notice appear in all copies and that both that copyright
|
|
* notice and this permission notice appear in supporting documentation, and
|
|
* that the name of the copyright holders not be used in advertising or
|
|
* publicity pertaining to distribution of the software without specific,
|
|
* written prior permission. The copyright holders make no representations
|
|
* about the suitability of this software for any purpose. It is provided "as
|
|
* is" without express or implied warranty.
|
|
*
|
|
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
|
|
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
|
|
* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
|
|
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
|
|
* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
|
|
* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
|
|
* OF THIS SOFTWARE.
|
|
*/
|
|
|
|
#include <drm/drmP.h>
|
|
#include <drm/drm_gem.h>
|
|
|
|
#include "drm_crtc_internal.h"
|
|
|
|
/**
|
|
* DOC: overview
|
|
*
|
|
* The KMS API doesn't standardize backing storage object creation and leaves it
|
|
* to driver-specific ioctls. Furthermore actually creating a buffer object even
|
|
* for GEM-based drivers is done through a driver-specific ioctl - GEM only has
|
|
* a common userspace interface for sharing and destroying objects. While not an
|
|
* issue for full-fledged graphics stacks that include device-specific userspace
|
|
* components (in libdrm for instance), this limit makes DRM-based early boot
|
|
* graphics unnecessarily complex.
|
|
*
|
|
* Dumb objects partly alleviate the problem by providing a standard API to
|
|
* create dumb buffers suitable for scanout, which can then be used to create
|
|
* KMS frame buffers.
|
|
*
|
|
* To support dumb objects drivers must implement the &drm_driver.dumb_create
|
|
* operation. &drm_driver.dumb_destroy defaults to drm_gem_dumb_destroy() if
|
|
* not set and &drm_driver.dumb_map_offset defaults to
|
|
* drm_gem_dumb_map_offset(). See the callbacks for further details.
|
|
*
|
|
* Note that dumb objects may not be used for gpu acceleration, as has been
|
|
* attempted on some ARM embedded platforms. Such drivers really must have
|
|
* a hardware-specific ioctl to allocate suitable buffer objects.
|
|
*/
|
|
|
|
int drm_mode_create_dumb_ioctl(struct drm_device *dev,
|
|
void *data, struct drm_file *file_priv)
|
|
{
|
|
struct drm_mode_create_dumb *args = data;
|
|
u32 cpp, stride, size;
|
|
|
|
if (!dev->driver->dumb_create)
|
|
return -ENOSYS;
|
|
if (!args->width || !args->height || !args->bpp)
|
|
return -EINVAL;
|
|
|
|
/* overflow checks for 32bit size calculations */
|
|
if (args->bpp > U32_MAX - 8)
|
|
return -EINVAL;
|
|
cpp = DIV_ROUND_UP(args->bpp, 8);
|
|
if (cpp > U32_MAX / args->width)
|
|
return -EINVAL;
|
|
stride = cpp * args->width;
|
|
if (args->height > U32_MAX / stride)
|
|
return -EINVAL;
|
|
|
|
/* test for wrap-around */
|
|
size = args->height * stride;
|
|
if (PAGE_ALIGN(size) == 0)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* handle, pitch and size are output parameters. Zero them out to
|
|
* prevent drivers from accidentally using uninitialized data. Since
|
|
* not all existing userspace is clearing these fields properly we
|
|
* cannot reject IOCTL with garbage in them.
|
|
*/
|
|
args->handle = 0;
|
|
args->pitch = 0;
|
|
args->size = 0;
|
|
|
|
return dev->driver->dumb_create(file_priv, dev, args);
|
|
}
|
|
|
|
/**
|
|
* drm_mode_mmap_dumb_ioctl - create an mmap offset for a dumb backing storage buffer
|
|
* @dev: DRM device
|
|
* @data: ioctl data
|
|
* @file_priv: DRM file info
|
|
*
|
|
* Allocate an offset in the drm device node's address space to be able to
|
|
* memory map a dumb buffer.
|
|
*
|
|
* Called by the user via ioctl.
|
|
*
|
|
* Returns:
|
|
* Zero on success, negative errno on failure.
|
|
*/
|
|
int drm_mode_mmap_dumb_ioctl(struct drm_device *dev,
|
|
void *data, struct drm_file *file_priv)
|
|
{
|
|
struct drm_mode_map_dumb *args = data;
|
|
|
|
if (!dev->driver->dumb_create)
|
|
return -ENOSYS;
|
|
|
|
if (dev->driver->dumb_map_offset)
|
|
return dev->driver->dumb_map_offset(file_priv, dev,
|
|
args->handle,
|
|
&args->offset);
|
|
else
|
|
return drm_gem_dumb_map_offset(file_priv, dev, args->handle,
|
|
&args->offset);
|
|
}
|
|
|
|
int drm_mode_destroy_dumb_ioctl(struct drm_device *dev,
|
|
void *data, struct drm_file *file_priv)
|
|
{
|
|
struct drm_mode_destroy_dumb *args = data;
|
|
|
|
if (!dev->driver->dumb_create)
|
|
return -ENOSYS;
|
|
|
|
if (dev->driver->dumb_destroy)
|
|
return dev->driver->dumb_destroy(file_priv, dev, args->handle);
|
|
else
|
|
return drm_gem_dumb_destroy(file_priv, dev, args->handle);
|
|
}
|
|
|