Commit d42f8d8767 for ffmpeg

commit d42f8d8767cb0d11fdbd5bf7c3dc2e426f97b3ca
Author: Marvin Scholz <epirat07@gmail.com>
Date:   Tue Sep 29 13:00:40 2026 +0000

    avformat/matroskadec: prevent duration float-cast-overflow

    Reset matroska->duration to 0 if it is negative or if matroska->duration *
    matroska->time_scale would exceed INT64_MAX, preventing a float-cast-overflow
    when calculating the duration.

    Signed-off-by: Marvin Scholz <epirat07@gmail.com>

diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index b793f67fa0..d36cc5c345 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -3506,7 +3506,8 @@ static int matroska_read_header(AVFormatContext *s)

     if (!matroska->time_scale)
         matroska->time_scale = 1000000;
-    if (isnan(matroska->duration))
+    if (isnan(matroska->duration) || matroska->duration < 0 ||
+        matroska->duration >= (double)INT64_MAX / matroska->time_scale)
         matroska->duration = 0;
     if (matroska->duration)
         matroska->ctx->duration = matroska->duration * matroska->time_scale *