[FFmpeg-cvslog] avformat/vqf: Check avio_read() in add_metadata()

[Michael Niedermayer]

ffmpeg | branch: release/4.3 | Michael Niedermayer <michael at niedermayer.cc> | Thu Dec 26 01:46:49 2024 +0100| [48118f2fae1f1eb50a0a4d6bc55bd91c5b5bf41d] | committer: Michael Niedermayer

avformat/vqf: Check avio_read() in add_metadata()

Fixes: use of uninitialized data
Fixes: 383825642/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5380168801124352

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit c43dbecbdad152a91eadc7538b545852eee562ae)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=48118f2fae1f1eb50a0a4d6bc55bd91c5b5bf41d
---

 libavformat/vqf.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libavformat/vqf.c b/libavformat/vqf.c
index 449f4061f7..bb0ff85285 100644
--- a/libavformat/vqf.c
+++ b/libavformat/vqf.c
@@ -61,7 +61,8 @@ static void add_metadata(AVFormatContext *s, uint32_t tag,
     buf = av_malloc(len+1);
     if (!buf)
         return;
-    avio_read(s->pb, buf, len);
+    if (len != avio_read(s->pb, buf, len))
+        return;
     buf[len] = 0;
     AV_WL32(key, tag);
     av_dict_set(&s->metadata, key, buf, AV_DICT_DONT_STRDUP_VAL);