avformat/paf: Check for EOF before allocation in read_header()

Fixes: OOM
Fixes: 26584/clusterfuzz-testcase-minimized-ffmpeg_dem_PAF_fuzzer-5172661183053824
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

diff --git a/libavformat/paf.c b/libavformat/paf.c
index 6183dc111533365dab9706fdce2386d0bab30a9c..dbc50100fb534542166b2d0140dbf7b0fed42702 100644 (file)
--- a/libavformat/paf.c
+++ b/libavformat/paf.c
@@ -136,6 +136,10 @@ static int read_header(AVFormatContext *s)
     p->start_offset   = avio_rl32(pb);
     p->max_video_blks = avio_rl32(pb);
     p->max_audio_blks = avio_rl32(pb);
+
+    if (avio_feof(pb))
+        return AVERROR_INVALIDDATA;
+
     if (p->buffer_size    < 175  ||
         p->max_audio_blks < 2    ||
         p->max_video_blks < 1    ||