From 163480b8591cdc4ccabccef4ff112d778afd1ced Mon Sep 17 00:00:00 2001
From: iliajie <gpg@ilia.engineer>
Date: Wed, 9 Nov 2022 20:04:29 +0200
Subject: [PATCH] Fix regex exclude chars logic
 https://github.com/webmin/webmin/pull/1776#discussion_r1017431635

---
 xterm/shellserver.pl | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/xterm/shellserver.pl b/xterm/shellserver.pl
index b5288eb0b..c2a3e4f93 100755
--- a/xterm/shellserver.pl
+++ b/xterm/shellserver.pl
@@ -117,12 +117,15 @@ Net::WebSocket::Server->new(
 				exit(0);
 				}
 			if ($wsconn) {
-				# Do not print commands to display, if start from two
-				# consecutive spaces and ends with return char. This
-				# regex only catches commands sent in one shot using
-				# socket.send('  command\r') call, i.e. it won't work
-				# if command is pasted or typed in a normal way
-				$buf =~ s/^[\s]{2}\S+.*[\r\n]+[\e]\[\?2004l[\n]*//;
+				# Do not print commands to display, if start from two and more spaces
+				# and ends with return char. Number of preceding spaces should equal
+				# the length of a command being executed. This regex only catches
+				# commands sent in one shot using socket.send('  ls\r') call, i.e.
+				# it won't work if command is pasted or typed in a normal way
+				if ($buf =~ /^([\s]{2,})(\S+.*)[\r\n]+[\e]\[\?2004l[\n]*/) {
+					$buf =~ s/^[\s]{2,}\S+.*[\r\n]+[\e]\[\?2004l[\n]*//
+						if (length($1) == length($2));
+					}
 				$wsconn->send_binary($buf);
 				}
 			else {