[238] in The Cryptographic File System users list
Re: Serious bug in cfs (1.4.1 and earlier)
daemon@ATHENA.MIT.EDU (Scott Renfro)
Mon Aug 27 05:09:41 2001
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Date: Mon, 27 Aug 2001 01:54:33 -0700
From: Scott Renfro <scott@renfro.org>
To: Martin Forssen <maf@tkrat.org>
Cc: cfs-users@research.att.com
Subject: Re: Serious bug in cfs (1.4.1 and earlier)
Message-ID: <20010827015433.B56428@bonsai.home.renfro.org>
References: <20010811203028.500213F5B6@tkrat.org>
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Funny thing. This has been bugging me for a *long* time (I even have a
script to fix up mail files when the leading 'F' in the "^From " header
gets dropped on mail processed via procmail). It hits several times a
day for me and is, indeed, serious (causes data loss).
Anyway, I sat down tonight and decided to hunt it down. After a good
bit of thought and code review, I came to the same conclusion, wrote a
very similar patch and mail message, and as I searched Google for the
cfs-users address, came across this message. Wish I had seen this a
couple of hours ago ;-)
Anyway, I'll also forward this off to the FreeBSD ports collection for
inclusion there until an updated cfs release is available.
cheers,
--Scott
On Sat, Aug 11, 2001 at 10:29:46PM +0200, Martin Forssen wrote:
>
> I have found what I consider a relatively serious bug in cfs. This
> applies to version 1.4.1 (the latest I could find) as well as earlier
> versions (at least 1.3.3).
>
> The bug is that under some circumstances cfsd looses small appends (<8
> bytes) to files (should happen 12% of the times). This results in
> corrupted files.
>
> The problem is that the way files are padded may actually require that
> the file is truncated when new data is written to it. And currently
> there is no code for doing that. The attached patch fixes this.
>
> /MaF
--
Scott Renfro <scott@renfro.org>
