[PATCH] Try to mitigate asan failures.

See #345 for my analysis and details…

(This PR is just for discussion.)

(The CVE references are obtained from the Debian security tracker,
which links the issues.)

This makes the following POCs stop failing:

- poc3 (#337)
- poc7-1 (#341) CVE-2022-43239 (note: does NOT fix poc7-2)
- poc8-2, poc8-3, poc8-4 (#342) CVE-2022-43244   (note: does NOT fix poc8-1)
- poc11-1, poc11-2 (#345) CVE-2022-43249
- poc12 (#346)
- poc13 (#347) CVE-2022-43252
- poc16 (#350)

Gbp-Pq: Name reject_reference_pics_from_different_sps.patch

diff --git a/libde265/motion.cc b/libde265/motion.cc
index 45d547b098ef9d8d75964b7f1ff4e1a6eb7befc2..b7d7abca6f20b273bafafa280ff046b47a5e0bf7 100644 (file)
--- a/libde265/motion.cc
+++ b/libde265/motion.cc
@@ -361,6 +361,16 @@ void generate_inter_prediction_samples(base_context* ctx,
 
       logtrace(LogMotion, "refIdx: %d -> dpb[%d]\n", vi->refIdx[l], shdr->RefPicList[l][vi->refIdx[l]]);
 
+      if (refPic) {
+          auto nonconst_refPic = const_cast<de265_image*>(refPic); /* shared_ptr.get() chokes on const.*/
+          auto refsps = nonconst_refPic->get_shared_sps().get();
+          auto imgsps = img->get_shared_sps().get();
+          if(refsps != imgsps) {
+              // rejecting reference image created with different sps.
+              refPic = nullptr;
+          }
+      }
+
       if (!refPic || refPic->PicState == UnusedForReference) {
         img->integrity = INTEGRITY_DECODING_ERRORS;
         ctx->add_warning(DE265_WARNING_NONEXISTING_REFERENCE_PICTURE_ACCESSED, false);