[FFmpeg-devel] [PATCH 2/2] avcodec/mvha: Check input size for HUFY before picture allocation

[Michael Niedermayer]

Fixes: Timeout
Fixes: 54772/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MVHA_fuzzer-5484199677394944

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/mvha.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/libavcodec/mvha.c b/libavcodec/mvha.c
index b1661c1c3b..55056c91cf 100644
--- a/libavcodec/mvha.c
+++ b/libavcodec/mvha.c
@@ -159,9 +159,6 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
     if (size < 1 || size >= avpkt->size)
         return AVERROR_INVALIDDATA;
 
-    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
-        return ret;
-
     if (type == MKTAG('L','Z','Y','V')) {
         z_stream *const zstream = &s->zstream.zstream;
         ret = inflateReset(zstream);
@@ -170,6 +167,9 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
             return AVERROR_EXTERNAL;
         }
 
+        if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+            return ret;
+
         zstream->next_in  = avpkt->data + 8;
         zstream->avail_in = avpkt->size - 8;
 
@@ -218,10 +218,16 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
             }
         }
 
+        if (get_bits_left(gb) < avctx->height * avctx->width)
+            return AVERROR_INVALIDDATA;
+
         ret = build_vlc(avctx, &s->vlc);
         if (ret < 0)
             return ret;
 
+        if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+            return ret;
+
         for (int p = 0; p < 3; p++) {
             int width = avctx->width >> (p > 0);
             ptrdiff_t stride = frame->linesize[p];
-- 
2.17.1