File _service:tar_scm:CVE-2020-35964.patch of Package ffmpeg

diff -Naru ffmpeg-4.2.4/libavformat/vividas.c ffmpeg-4.2.4-new/libavformat/vividas.c
--- ffmpeg-4.2.4/libavformat/vividas.c	2022-05-24 10:57:25.967425000 +0800
+++ ffmpeg-4.2.4-new/libavformat/vividas.c	2022-05-24 11:07:17.698072000 +0800
@@ -27,7 +27,7 @@
  * @author Andrzej Szombierski [qq at kuku eu org] (2010-07)
  * @sa http://wiki.multimedia.cx/index.php?title=Vividas_VIV
  */
-
+#include "libavutil/avassert.h"
 #include "libavutil/intreadwrite.h"
 #include "avio_internal.h"
 #include "avformat.h"
@@ -278,7 +278,7 @@
 
 static int track_header(VividasDemuxContext *viv, AVFormatContext *s,  uint8_t *buf, int size)
 {
-    int i,j;
+    int i, j, ret;
     int64_t off;
     int val_1;
     int num_video;
@@ -372,7 +372,7 @@
 
         if (avio_tell(pb) < off) {
             int num_data;
-            int xd_size = 0;
+            int xd_size = 1;
             int data_len[256];
             int offset = 1;
             uint8_t *p;
@@ -387,24 +387,19 @@
                     return AVERROR_INVALIDDATA;
                 }
                 data_len[j] = len;
-                xd_size += len;
+                xd_size += len + 1 + len/255;
             }
 
-            st->codecpar->extradata_size = 64 + xd_size + xd_size / 255;
-            if (ff_alloc_extradata(st->codecpar, st->codecpar->extradata_size)) {
-                av_free(pb);
-                return AVERROR(ENOMEM);
-            }
+            ret = ff_alloc_extradata(st->codecpar, xd_size);
+            if (ret < 0)
+                return ret;
 
             p = st->codecpar->extradata;
             p[0] = 2;
 
             for (j = 0; j < num_data - 1; j++) {
                 unsigned delta = av_xiphlacing(&p[offset], data_len[j]);
-                if (delta > data_len[j]) {
-                    av_free(pb);
-                    return AVERROR_INVALIDDATA;
-                }
+                av_assert0(delta <= xd_size - offset);
                 offset += delta;
             }
 
@@ -415,6 +410,7 @@
                     av_freep(&st->codecpar->extradata);
                     break;
                 }
+                av_assert0(data_len[j] <= xd_size - offset);
                 offset += data_len[j];
             }