[66] in The Cryptographic File System users list
Re: Annoying CFS bug fixed
daemon@ATHENA.MIT.EDU (Rob Stampfli)
Sun Apr 26 20:21:12 1998
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Date: Sun, 26 Apr 98 19:59 EDT
From: res@kd8wk.cmhnet.org (Rob Stampfli)
To: cfs-users@research.att.com
Subject: Re: Annoying CFS bug fixed
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In recent email Sean Sheedy writes:
>
>The current version of CFS has a bug where the modification time is
>changed on the file even if it is opened only for read. I've attached a
>patch to fix this bug. Also, this patch has a change to avoid an
>unnecessary truncate when the file isn't actually shrinking.
>
>Sean
...
>*** cfs_fh.c 1998/01/02 07:12:25 1.1
>--- cfs_fh.c 1998/03/14 00:18:10
>***************
>*** 547,553 ****
> openfd=NULL;
> }
>
>! if (mode==0) { mode=CFS_WRITE; }
> /* Phil Karn's hack for R/O file systems */
> if ((fd=open(f->name,mode,0))<0 && errno == EROFS) {
> mode = CFS_READ; /* Force read and try again */
>--- 547,554 ----
> openfd=NULL;
> }
>
>! /* ### This looks badly wrong */
>! /* if (mode==0) { mode=CFS_WRITE; } */
> /* Phil Karn's hack for R/O file systems */
> if ((fd=open(f->name,mode,0))<0 && errno == EROFS) {
> mode = CFS_READ; /* Force read and try again */
Thanks, Sean. I'll make this change to my copy and look for it in the
next release of cfs.
Your mail prompted me to examine this file, and it looks like there may
be a very minor bug in the section right above it, too: There is a static
variable curfd which contains a file descriptor to the "working" file. I
would recommend adding the line: "curfd = -1;" immediately after the line
"close(curfd); /* hope it was valid... */", to prevent doing multiple
close()s on the file. Most Unixes would take this in stride, but there
might be some strange version somewhere that would get upset.
Also, does anyone on the group use esm? I do, and I've hacked my esm.c
to ignore ctrl-S and ctrl-Q in the stream while exchanging keys and while
running in ecrypted mode. I have found that this is necessary for it to
work in certain conditions (like when there is a "cu" or "tip" in the
pipeline). I can provide the diffs, if anyone is interested.
My 2 cents on a rainy Sunday afternoon...
--
Rob Stampfli rob@colnet.cmhnet.org The Bill of Rights: It was a
614-864-9377 HAM RADIO: kd8wk@w8cqk.oh good thing while it lasted...
