From b62f7e243cf4a1863ee4131e55536338eacecc6c Mon Sep 17 00:00:00 2001
From: Paul B Mahol <onemda@gmail.com>
Date: Fri, 11 Oct 2019 12:23:26 +0200
Subject: [PATCH] avfilter/vf_deflicker: fix invalid access

Fixes #8253
---
 libavfilter/vf_deflicker.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libavfilter/vf_deflicker.c b/libavfilter/vf_deflicker.c
index b038b977f6..ea3f430a05 100644
--- a/libavfilter/vf_deflicker.c
+++ b/libavfilter/vf_deflicker.c
@@ -420,7 +420,10 @@ static int request_frame(AVFilterLink *outlink)
 
     ret = ff_request_frame(ctx->inputs[0]);
     if (ret == AVERROR_EOF && s->available > 0) {
-        AVFrame *buf = av_frame_clone(ff_bufqueue_peek(&s->q, s->size - 1));
+        AVFrame *buf = ff_bufqueue_peek(&s->q, s->available - 1);
+        if (!buf)
+            return AVERROR(ENOMEM);
+        buf = av_frame_clone(buf);
         if (!buf)
             return AVERROR(ENOMEM);