[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 8bbfbde0eb2be1aacf0caa3ee10212c8ce8e5436..1d20bcd3ca02a24bb6c439be7bf01c9fe646dc3f 100644 (file)
--- a/libde265/motion.cc
+++ b/libde265/motion.cc
@@ -348,6 +348,16 @@ 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);