[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 c8e8db9175624a09c813fe7a88a214fe5014f9a0..78192b26abae84631d1fb47b7c6b90e88edc8966 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);