From 403bee30a57bfa77efebddcebc546df9d3876db2 Mon Sep 17 00:00:00 2001
From: Limin Wang <lance.lmwang@gmail.com>
Date: Sun, 29 Mar 2020 08:08:04 +0800
Subject: [PATCH] avfilter/af_acrossover: Check sscanf() return value

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
---
 libavfilter/af_acrossover.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libavfilter/af_acrossover.c b/libavfilter/af_acrossover.c
index f70c50b3ed..002f378c3d 100644
--- a/libavfilter/af_acrossover.c
+++ b/libavfilter/af_acrossover.c
@@ -99,7 +99,10 @@ static av_cold int init(AVFilterContext *ctx)
 
         p = NULL;
 
-        av_sscanf(arg, "%f", &freq);
+        if (av_sscanf(arg, "%f", &freq) != 1) {
+            av_log(ctx, AV_LOG_ERROR, "Invalid syntax for frequency[%d].\n", i);
+            return AVERROR(EINVAL);
+        }
         if (freq <= 0) {
             av_log(ctx, AV_LOG_ERROR, "Frequency %f must be positive number.\n", freq);
             return AVERROR(EINVAL);