On 22/02/2022 10:36, Jordan Justen wrote:
i915_drm.h now defines the format of the returned DRM_I915_QUERY_HWCONFIG_BLOB query item. Since i915 receives this from the black box GuC software, it should verify that the data matches that format before sending it to user-space.
The verification makes a single simple pass through the blob contents, so this verification step should not add a significant amount of init time to i915.
v3:
- Add various changes suggested by Tvrtko
v4:
- Rewrite verify_hwconfig_blob() to hopefully be clearer without relying on comments so much, and add various suggestions from Michal.
Signed-off-by: Jordan Justen jordan.l.justen@intel.com Acked-by: Jon Bloomfield jon.bloomfield@intel.com
.../gpu/drm/i915/gt/uc/intel_guc_hwconfig.c | 44 ++++++++++++++++++- 1 file changed, 43 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_hwconfig.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_hwconfig.c index ad289603460c..a844b880cbdb 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_hwconfig.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_hwconfig.c @@ -73,9 +73,46 @@ static int guc_hwconfig_discover_size(struct intel_guc_hwconfig *hwconfig) return 0; }
+static int verify_hwconfig_blob(struct intel_guc_hwconfig *hwconfig) +{
- struct intel_guc *guc = hwconfig_to_guc(hwconfig);
- struct drm_device *drm = &guc_to_gt(guc)->i915->drm;
- struct drm_i915_query_hwconfig_blob_item *item = hwconfig->ptr;
- u64 offset = 0;
- u64 remaining = hwconfig->size;
- /* Everything before the data field is required */
- u64 min_item_size = offsetof(struct drm_i915_query_hwconfig_blob_item, data);
- u64 item_size;
- if (!IS_ALIGNED(hwconfig->size, sizeof(u32))) {
drm_err(drm, "hwconfig blob size (%d) is not u32 aligned\n", hwconfig->size);return -EINVAL;- }
- while (offset < hwconfig->size) {
if (remaining < min_item_size) {drm_err(drm, "hwconfig blob invalid (no room for item required fields at offset %lld)\n",offset);return -EINVAL;}item_size = min_item_size + sizeof(u32) * item->length;if (item_size > remaining) {drm_err(drm, "hwconfig blob invalid (no room for data array of item at offset %lld)\n",offset);return -EINVAL;}offset += item_size;remaining -= item_size;item = (void *)&item->data[item->length];- }
- return 0;
+}
- static int guc_hwconfig_fill_buffer(struct intel_guc_hwconfig *hwconfig) { struct intel_guc *guc = hwconfig_to_guc(hwconfig);
- struct drm_device *drm = &guc_to_gt(guc)->i915->drm; struct i915_vma *vma; u32 ggtt_offset; void *vaddr;
@@ -90,8 +127,13 @@ static int guc_hwconfig_fill_buffer(struct intel_guc_hwconfig *hwconfig) ggtt_offset = intel_guc_ggtt_offset(guc, vma);
ret = __guc_action_get_hwconfig(guc, ggtt_offset, hwconfig->size);
- if (ret >= 0)
if (ret >= 0) { memcpy(hwconfig->ptr, vaddr, hwconfig->size);
if (verify_hwconfig_blob(hwconfig)) {drm_err(drm, "Ignoring invalid hwconfig blob received from GuC!\n");ret = -EINVAL;}}
i915_vma_unpin_and_release(&vma, I915_VMA_RELEASE_MAP);
Reviewed-by: Tvrtko Ursulin tvrtko.ursulin@intel.com
Regards,
Tvrtko