From 5ef7c84a9374681c64722a96d91741f3b990af2b Mon Sep 17 00:00:00 2001
From: Luca Barbato <lu_zero@gentoo.org>
Date: Wed, 14 Aug 2013 16:51:53 +0200
Subject: [PATCH] dxa: Make sure the reference frame exists

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
---
 libavcodec/dxa.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavcodec/dxa.c b/libavcodec/dxa.c
index 9e7f453b08..ddc31f3413 100644
--- a/libavcodec/dxa.c
+++ b/libavcodec/dxa.c
@@ -255,6 +255,10 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
     case 3:
     case 4:
     case 5:
+        if (!tmpptr) {
+            av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
+            return AVERROR_INVALIDDATA;
+        }
         frame->key_frame = !(compr & 1);
         frame->pict_type = (compr & 1) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
         for(j = 0; j < avctx->height; j++){