Commit 42e81e00c6 for ffmpeg

commit 42e81e00c67d0446307bf3f5e43a9d4082d48bec
Author: Michael Niedermayer <michael@niedermayer.cc>
Date:   Sat Oct 10 05:23:52 2026 +0200

    avcodec/vvc/cabac: reject entropy coding sync without entry points

    Undefined shift Replicated through UnModified FFmpeg with UBSAN

    Fixes: left shift of 539332544 by 2 places cannot be represented in type 'int'
    Fixes: 543314355/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VVC_fuzzer-6530021460869120
    Fixes: zNquwYqrjFd2

    Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
    Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavcodec/vvc/cabac.c b/libavcodec/vvc/cabac.c
index e386cdf4c8..329172e475 100644
--- a/libavcodec/vvc/cabac.c
+++ b/libavcodec/vvc/cabac.c
@@ -855,6 +855,10 @@ int ff_vvc_cabac_init(VVCLocalContext *lc,
             ret = cabac_reinit(lc);
         if (!ret)
             cabac_init_state(lc);
+    } else if (lc->sc->nb_eps == 1 && rx == pps->ctb_to_col_bd[rx] &&
+               lc->fc->ps.sps->r->sps_entropy_coding_sync_enabled_flag) {
+        avpriv_report_missing_feature(lc->fc->log_ctx, "Entropy coding sync without entry points");
+        return AVERROR_PATCHWELCOME;
     }
     return ret;
 }