diff options
| author |   Matthew Auld <matthew.auld@intel.com> | 2020-01-17 13:24:12 +0000 |
|---|---|---|
| committer |   Chris Wilson <chris@chris-wilson.co.uk> | 2020-01-17 19:14:03 +0000 |
| commit | 24860ad748688b1156472d734b88b5d8d32fa42a (patch) | |
| tree | 84806692817c225bb878abde579a7c9e6ed7f3de /drivers/gpu/drm/i915/gem/i915_gem_userptr.c | |
| parent | drm/i915/gt: Report the currently active execlists request (diff) | |
| download | linux-dev-24860ad748688b1156472d734b88b5d8d32fa42a.tar.xz linux-dev-24860ad748688b1156472d734b88b5d8d32fa42a.zip | |
drm/i915/userptr: add user_size limit check
Don't allow a mismatch between obj->base.size/vma->size and the actual
number of pages for the backing store, which is limited to INT_MAX
pages.
v2: document what are missing before we can safely drop the limit check
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200117132413.1170563-1-matthew.auld@intel.com
Diffstat (limited to 'drivers/gpu/drm/i915/gem/i915_gem_userptr.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c index e5558af111e2..b64b0f383a56 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c @@ -769,6 +769,23 @@ i915_gem_userptr_ioctl(struct drm_device *dev, I915_USERPTR_UNSYNCHRONIZED)) return -EINVAL; + /* + * XXX: There is a prevalence of the assumption that we fit the + * object's page count inside a 32bit _signed_ variable. Let's document + * this and catch if we ever need to fix it. In the meantime, if you do + * spot such a local variable, please consider fixing! + * + * Aside from our own locals (for which we have no excuse!): + * - sg_table embeds unsigned int for num_pages + * - get_user_pages*() mixed ints with longs + */ + + if (args->user_size >> PAGE_SHIFT > INT_MAX) + return -E2BIG; + + if (overflows_type(args->user_size, obj->base.size)) + return -E2BIG; + if (!args->user_size) return -EINVAL; |