From 0ca33b1d4eb2a2a2e78ff3a37f1647917635b0d2 Mon Sep 17 00:00:00 2001
From: James Almer <jamrial@gmail.com>
Date: Tue, 6 Mar 2018 01:19:13 -0300
Subject: [PATCH] avformat/utils: free existing extradata before trying to
 allocate a new one

This prevents leaks in the rare cases the function is called when extradata
already exists.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
---
 libavformat/utils.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libavformat/utils.c b/libavformat/utils.c
index 72531d4185..31340a484b 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -3245,6 +3245,7 @@ int ff_alloc_extradata(AVCodecParameters *par, int size)
 {
     int ret;
 
+    av_freep(&par->extradata);
     if (size < 0 || size >= INT32_MAX - AV_INPUT_BUFFER_PADDING_SIZE) {
         par->extradata = NULL;
         par->extradata_size = 0;