From 9f54c13bc4650c59fe2ffb04f5b85145f196fbb7 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Sat, 27 Apr 2024 20:51:45 +0200
Subject: [PATCH] avformat/iamfdec: check nb_streams in header read

Fixes: Assertion pkt->stream_index < (unsigned)s->nb_streams && "Invalid stream index.\n" failed at libavformat/demux.c:572
Fixes: 67890/clusterfuzz-testcase-minimized-ffmpeg_dem_IAMF_fuzzer-5166340789829632.fuzz

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavformat/iamfdec.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavformat/iamfdec.c b/libavformat/iamfdec.c
index e34d13e74c..ce6d4aa064 100644
--- a/libavformat/iamfdec.c
+++ b/libavformat/iamfdec.c
@@ -154,6 +154,9 @@ static int iamf_read_header(AVFormatContext *s)
         }
     }
 
+    if (!s->nb_streams)
+        return AVERROR_INVALIDDATA;
+
     return 0;
 }