drm/i915: Rephrase pwrite bounds checking to avoid any potential overflow
... and do the same for pread.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 7749e78..aa959c4a 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -471,12 +471,8 @@
return -ENOENT;
obj_priv = to_intel_bo(obj);
- /* Bounds check source.
- *
- * XXX: This could use review for overflow issues...
- */
- if (args->offset > obj->size || args->size > obj->size ||
- args->offset + args->size > obj->size) {
+ /* Bounds check source. */
+ if (args->offset > obj->size || args->size > obj->size - args->offset) {
ret = -EINVAL;
goto err;
}
@@ -939,12 +935,8 @@
return -ENOENT;
obj_priv = to_intel_bo(obj);
- /* Bounds check destination.
- *
- * XXX: This could use review for overflow issues...
- */
- if (args->offset > obj->size || args->size > obj->size ||
- args->offset + args->size > obj->size) {
+ /* Bounds check destination. */
+ if (args->offset > obj->size || args->size > obj->size - args->offset) {
ret = -EINVAL;
goto err;
}