From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262591AbVFJQFf (ORCPT ); Fri, 10 Jun 2005 12:05:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262592AbVFJQFf (ORCPT ); Fri, 10 Jun 2005 12:05:35 -0400 Received: from fest.stud.feec.vutbr.cz ([147.229.72.16]:1217 "EHLO fest.stud.feec.vutbr.cz") by vger.kernel.org with ESMTP id S262591AbVFJQFa (ORCPT ); Fri, 10 Jun 2005 12:05:30 -0400 Message-ID: <42A9BA87.4010600@stud.feec.vutbr.cz> Date: Fri, 10 Jun 2005 18:06:31 +0200 From: Michal Schmidt User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050317) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Alastair Poole CC: linux-kernel@vger.kernel.org Subject: Re: BUG: Unusual TCP Connect() results. References: <42A8ABDB.6080804@unixtrix.com> <42A9B193.1020602@stud.feec.vutbr.cz> <42A9C607.4030209@unixtrix.com> In-Reply-To: <42A9C607.4030209@unixtrix.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alastair Poole wrote: > This problem only occurs on localhost. I don't think it is mere luck, > these are too frequent and strange for this. I tried the scanning program on localhost. I modified it to wait for the user to press Enter when it encounters an open port. On my system I normally have listening TCP ports 25, 631 and 1024. And yes, the scanning program sometimes finds other open ports. This is netstat output when it happens: michich@michichnb:~> LC_ALL=C netstat -ntp | grep scan (Not all processes could be identified, non-owned process info will not be shown, you would have to be root to see it all.) tcp 0 0 127.0.0.1:1774 127.0.0.1:1774 ESTABLISHED 17510/scan The TCP socket connected to itself. I don't know if it's expected behaviour. It agree it is strange, because we didn't call listen() on the socket. Michal