Merge commit '0ebb523f'

* commit '0ebb523f':
  asfdec: check ff_get_guid() return values during seeking

Conflicts:
	libavformat/asfdec.c

The code that pretends that a truncated index is correct and complete is not merged
as it obviously would cause problems if a really truncated index is encountered
If someone has samples that work better with that hack, please share them / mail me

also the bug this apparently attempts to fix isnt reproducable before this in ffmpeg
Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/asfdec.c

@@ -1456,30 +1456,30 @@ static int64_t asf_read_pts(AVFormatContext *s, int stream_index,
     return pts;
 }
 
-static void asf_build_simple_index(AVFormatContext *s, int stream_index)
+static int asf_build_simple_index(AVFormatContext *s, int stream_index)
 {
     ff_asf_guid g;
     ASFContext *asf     = s->priv_data;
     int64_t current_pos = avio_tell(s->pb);
+    int ret = 0;
 
     if(avio_seek(s->pb, asf->data_object_offset + asf->data_object_size, SEEK_SET) < 0) {
-        asf->index_read= -1;
-        return;
+        return AVERROR_INVALIDDATA;
     }
 
-    ff_get_guid(s->pb, &g);
+    if ((ret = ff_get_guid(s->pb, &g)) < 0)
+        goto end;
 
     /* the data object can be followed by other top-level objects,
      * skip them until the simple index object is reached */
     while (ff_guidcmp(&g, &ff_asf_simple_index_header)) {
         int64_t gsize = avio_rl64(s->pb);
         if (gsize < 24 || url_feof(s->pb)) {
-            avio_seek(s->pb, current_pos, SEEK_SET);
-            asf->index_read= -1;
-            return;
+            goto end;
         }
         avio_skip(s->pb, gsize - 24);
-        ff_get_guid(s->pb, &g);
+        if ((ret = ff_get_guid(s->pb, &g)) < 0)
+            goto end;
     }
 
     {
@@ -1487,7 +1487,8 @@ static void asf_build_simple_index(AVFormatContext *s, int stream_index)
         int pct, ict;
         int i;
         int64_t av_unused gsize = avio_rl64(s->pb);
-        ff_get_guid(s->pb, &g);
+        if ((ret = ff_get_guid(s->pb, &g)) < 0)
+            goto end;
         itime = avio_rl64(s->pb);
         pct   = avio_rl32(s->pb);
         ict   = avio_rl32(s->pb);
@@ -1510,7 +1511,12 @@ static void asf_build_simple_index(AVFormatContext *s, int stream_index)
         }
         asf->index_read = ict > 1;
     }
+end:
+//     if (url_feof(s->pb)) {
+//         ret = 0;
+//     }
     avio_seek(s->pb, current_pos, SEEK_SET);
+    return ret;
 }
 
 static int asf_read_seek(AVFormatContext *s, int stream_index,
@@ -1518,6 +1524,7 @@ static int asf_read_seek(AVFormatContext *s, int stream_index,
 {
     ASFContext *asf = s->priv_data;
     AVStream *st    = s->streams[stream_index];
+    int ret = 0;
 
     if (s->packet_size <= 0)
         return -1;
@@ -1531,10 +1538,13 @@ static int asf_read_seek(AVFormatContext *s, int stream_index,
             return ret;
     }
 
-    if (!asf->index_read)
-        asf_build_simple_index(s, stream_index);
+    if (!asf->index_read) {
+        ret = asf_build_simple_index(s, stream_index);
+        if (ret < 0)
+            asf->index_read = -1;
+    }
 
-    if ((asf->index_read > 0 && st->index_entries)) {
+    if (asf->index_read > 0 && st->index_entries) {
         int index = av_index_search_timestamp(st, pts, flags);
         if (index >= 0) {
             /* find the position */