Mailing-List: contact cygwin-help AT sourceware DOT cygnus DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT sources DOT redhat DOT com Delivered-To: mailing list cygwin AT sources DOT redhat DOT com Message-Id: <5.1.0.14.0.20010621085251.040efec0@mail> X-Sender: superbiskit AT mail X-Mailer: QUALCOMM Windows Eudora Version 5.1 Date: Thu, 21 Jun 2001 08:59:52 -0400 To: Alois DOT Steindl AT tuwien DOT ac DOT at, Cygwin General MailList From: "David A. Cobb" Subject: Re: * Re: 1.1.8: Too large entry in termcap file In-Reply-To: <01062110062500.00883@mch2pc28> References: <5 DOT 1 DOT 0 DOT 14 DOT 0 DOT 20010620162323 DOT 00ac0510 AT mail> <5 DOT 1 DOT 0 DOT 14 DOT 0 DOT 20010620162323 DOT 00ac0510 AT mail> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed Alois, I hope you don't mind that I've posted this also on the list. At 6/21/01 04:06 AM (Thursday), you wrote: >Hello, >thanks for your reply. > >On Wednesday 20 June 2001 22:27, you wrote: > > > > [cgf:] To say nothing of security breaches. I've had 3 BugTraq notices in > > 2 days about buffer overrun exploits in code that we include with Cygwin. > > >since English isn't my first language: >Does this mean that you have encountered buffer overrun problems in code from >cygwin or in code from users, who use programs (and libraries) from the >cygwin project to compile/run their code? In utilities that are included in the Cygwin download. I cannot be certain that the codebase is the same. To be more precise: one reported for rxvt by Debian, one in fetchmail - I now realize there's no "official" cygwin fetchmail, and one in an AIX version of rsh.gethostbyname() - and who knows whether their codebase is the same. So I was slightly hasty. A very common type of vulnerability in any case. >To me it seems that any potential source of buffer overruns should be >avoided. It's also quite dangerous to increase the required buffer length, >since users of free software will almost certainly not be aware of the >necessity to look at any included sub-project individually. >In my case I tried to install the fweb package, which I have used frequently >on mainly unixoid systems on a notebook with cygwin. The installation worked >successfully, but the program crashed. It took me quite a while until I >figured out that the problem was a buffer overrun in a termcap routine. >Although I rather quickly suspected tgetent() to be the problem, I needed >several hours to find the reason: I compared the description from the manual >with the code surrounding the call and everything seemed to be fine. Then I >realized that changing the TERM variable to vt100 avoided the crashes. >Looking at the termcap file I got the impression that the linux entry, which >is pointed to by the cygwin entry, is very large and then realized, that it >is larger than the 1024 bytes. >Even if the man pages would have been correct, it would have taken some time >to find the reason for the crashes. > >Alois David A. Cobb, Software Engineer, Public Access Advocate, All around nice guy. Get my PGP key at : Fingerprint=0x{6E3E_DB8C_2E8C_4248_62B2_FE29_08EE_CF0A_3629_E954} "By God's Grace I am a Christian man, by my actions a great sinner." --The Way of a Pilgrim, R. M. French [tr.] <---.----!----.----!----.----!----.----!----.----!----.----!----.----> -- Want to unsubscribe from this list? Check out: http://cygwin.com/ml/#unsubscribe-simple