From 6c0823454ef075fedacf0b155e088ffc447985d6 Mon Sep 17 00:00:00 2001
From: yefeng <yefeng@kylinos.com.cn>
Date: Wed, 20 Apr 2022 13:43:22 +0800
Subject: [PATCH] Fix stack-buffer-overflow at zlog_conf_build_with_file

    -#53811
---
 src/conf.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/conf.c b/src/conf.c
index a947178..258a59a 100644
--- a/src/conf.c
+++ b/src/conf.c
@@ -276,6 +276,7 @@ static int zlog_conf_build_with_file(zlog_conf_t * a_conf)
 	 */
 	pline = line;
 	memset(&line, 0x00, sizeof(line));
+    //循环读取配置文件的一行
 	while (fgets((char *)pline, sizeof(line) - (pline - line), fp) != NULL) {
 		++line_no;
 		line_len = strlen(pline);
@@ -304,12 +305,13 @@ static int zlog_conf_build_with_file(zlog_conf_t * a_conf)
 		for (p = pline + strlen(pline) - 1; isspace((int)*p); --p)
 			/*EMPTY*/;
 
+        //处理结束符为 '\\' 的特殊情况, 在这种情况下,当前行与下面一行并做一行处理
 		if (*p == '\\') {
 			if ((p - line) > MAXLEN_CFG_LINE - 30) {
 				/* Oops the buffer is full - what now? */
 				pline = line;
 			} else {
-				for (p--; isspace((int)*p); --p)
+                for(p--; p >= line && isspace((int)*p); --p)
 					/*EMPTY*/;
 				p++;
 				*p = 0;
-- 
2.31.1