From 2ed47ab72509bbee60288d245a0aebb7eb05e41a Mon Sep 17 00:00:00 2001
From: Marvin Scholz <epirat07@gmail.com>
Date: Fri, 22 Aug 2025 16:50:34 +0200
Subject: [PATCH] avformat/rtsp: do not log invalid values

When reading fails the first time, ch would be uninitialized and
printed in the log message. Instead check for an error early and
log it properly.
---
 libavformat/rtsp.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
index 10355b89b8..13507d1858 100644
--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -1239,9 +1239,12 @@ start:
         q = buf;
         for (;;) {
             ret = ffurl_read_complete(rt->rtsp_hd, &ch, 1);
+            if (ret != 1) {
+                ret = (ret < 0) ? ret : AVERROR(EIO);
+                av_log(s, AV_LOG_WARNING, "Failed reading RTSP data: %s\n", av_err2str(ret));
+                return ret;
+            }
             av_log(s, AV_LOG_TRACE, "ret=%d c=%02x [%c]\n", ret, ch, ch);
-            if (ret != 1)
-                return ret < 0 ? ret : AVERROR(EIO);
             if (ch == '\n')
                 break;
             if (ch == '$' && q == buf) {