avcodec/rscc: Check inflated_buf size whan it is used

Fixes: out of array access
Fixes: 27434/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_RSCC_fuzzer-5196757675540480
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg

diff --git a/libavcodec/rscc.c b/libavcodec/rscc.c
index bd0520950ff323164344d4a0f73a3ea9f60ff5a6..07a7c3dca3b4723788a4856aa05f61446ede5e1c 100644 (file)
--- a/libavcodec/rscc.c
+++ b/libavcodec/rscc.c
@@ -300,6 +300,10 @@ static int rscc_decode_frame(AVCodecContext *avctx, void *data,
             ret = AVERROR_INVALIDDATA;
             goto end;
         }
+        if (ctx->inflated_size < pixel_size) {
+            ret = AVERROR_INVALIDDATA;
+            goto end;
+        }
         ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size);
         if (ret) {
             av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret);