linux-zen-server/drivers/gpu/drm/i915/i915_user_extensions.c

62 lines
1.1 KiB
C

/*
* SPDX-License-Identifier: MIT
*
* Copyright © 2018 Intel Corporation
*/
#include <linux/nospec.h>
#include <linux/sched/signal.h>
#include <linux/uaccess.h>
#include <uapi/drm/i915_drm.h>
#include "i915_user_extensions.h"
#include "i915_utils.h"
int i915_user_extensions(struct i915_user_extension __user *ext,
const i915_user_extension_fn *tbl,
unsigned int count,
void *data)
{
unsigned int stackdepth = 512;
while (ext) {
int i, err;
u32 name;
u64 next;
if (!stackdepth--) /* recursion vs useful flexibility */
return -E2BIG;
err = check_user_mbz(&ext->flags);
if (err)
return err;
for (i = 0; i < ARRAY_SIZE(ext->rsvd); i++) {
err = check_user_mbz(&ext->rsvd[i]);
if (err)
return err;
}
if (get_user(name, &ext->name))
return -EFAULT;
err = -EINVAL;
if (name < count) {
name = array_index_nospec(name, count);
if (tbl[name])
err = tbl[name](ext, data);
}
if (err)
return err;
if (get_user(next, &ext->next_extension) ||
overflows_type(next, uintptr_t))
return -EFAULT;
ext = u64_to_user_ptr(next);
}
return 0;
}