[9fans] 4th edition file server available

[9fans] 4th edition file server available

[Russ Cox]

The new 4th edition file server, named Fossil,
is now available on sources.  There are some
how-to docs for setting up Venti and Fossil at:

http://plan9.bell-labs.com/wiki/plan9/setting_up_venti
http://plan9.bell-labs.com/wiki/plan9/setting_up_fossil

The man pages fossil(4) and fossilcons(8) are
the definitive reference.  /sys/doc/fossil.pdf (aka
http://plan9.bell-labs.com/sys/doc/fossil.pdf)
describes the disk structures and also the Vac
structures for those interested in hacking the
internals.

Conceptually, Fossil is similar to the current file server
with Venti instead of a WORM juke box, but practically
there are many other differences.  It is a user-level
program rather than a special kernel, it speaks 9P2000
(and not 9P1), and there are numerous other improvements,
including enormous file names and also soft updates so that
the disk image is always in a consistent state.

It is still a work in progress, but it's ready to be used
by those feeling adventurous.

Enjoy.
Sean, Jim, Russ


g% x=`{perl -e 'print "a"x2000'}
g% >$x
g% ls -l $x
--rw-rw-r-- M 8 rsc rsc 0 Jan  8 01:30 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
g%

Re: [9fans] 4th edition file server available

[Axel Belinfante]

Congratulations!

I feel a bit adventurous -- but also in the need of
a little (or more?) hand-holding.

I have browsed through the setting up docs on wiki,
and a couple of the refered man pages, but
could not easily see how to build a fossil from
(to replace) an existing fake-worm file server,
taking into account the dump partition.

I recall reading before that at bell labs worm
disks of the fs were copied ``by hand'' one by one,
by taking them out of the fs.
Is there a way to transfer dump to fossil from
a running fake-worm fs (so, just using normal 9p
access, without going to the ``raw disks'')?

On a related note: my fake-worm fs uses relatively small
blocks (4Kb). Can I freely choose a block size for the
venti underlying the fossil, or should there be
a strict relation between the fake-worm  block size
and the fossil/venti block size (e.g. due to transfer
of dump blocks)?

Thanks for any insight (pointers welcome),
Axel.

> The new 4th edition file server, named Fossil,
> is now available on sources.  There are some
> how-to docs for setting up Venti and Fossil at:
[snip] 
> It is still a work in progress, but it's ready to be used
> by those feeling adventurous.

Re: [9fans] 4th edition file server available

[Fco.J.Ballesteros]

[-- Attachment #1: Type: text/plain, Size: 912 bytes --]

Not to fossil, but we're using this to move our worm into vac, which
can be serviced by venti. 9fs automates it for us.

#!/bin/rc
# mkvac: creates one vac archive. argument is day number.
#

srv -q il!sargazos.escet.urjc.es
mount /srv/il!sargazos.escet.urjc.es /n/dump dump
date
vname=`{echo $1 | sed 's|/|_|g'}
lname=`{cat mkvac.last}
echo vac -s -b16k -f dump/2002/$vname.vac -d dump/2002/$lname -q /n/dump/$1
time vac -s -b16k -f dump/2002/$vname.vac -d dump/2002/$lname -q /n/dump/$1
echo echo $vname.vac '>' mkvac.last
 echo $vname.vac > mkvac.last
unmount /n/dump
rm /srv/il!sargazos.escet.urjc.es
date


This other one calls the previous one to automate it:
#!/bin/rc
days=(0508 0507 0506 .....other preferred days here)
for (d in $days) {
	cp /dev/text /n/once/nemo/mkvacs.out
	echo -n $d starts ' '
	mkvac 2002/$d
	echo
}
exit


We are doing 1.5 months per day or so.

[-- Attachment #2: Type: message/rfc822, Size: 3844 bytes --]

From: Axel Belinfante <Axel.Belinfante@cs.utwente.nl>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] 4th edition file server available
Date: Wed, 08 Jan 2003 12:09:07 +0100
Message-ID: <200301081109.h08B97629776@zamenhof.cs.utwente.nl>

Congratulations!

I feel a bit adventurous -- but also in the need of
a little (or more?) hand-holding.

I have browsed through the setting up docs on wiki,
and a couple of the refered man pages, but
could not easily see how to build a fossil from
(to replace) an existing fake-worm file server,
taking into account the dump partition.

I recall reading before that at bell labs worm
disks of the fs were copied ``by hand'' one by one,
by taking them out of the fs.
Is there a way to transfer dump to fossil from
a running fake-worm fs (so, just using normal 9p
access, without going to the ``raw disks'')?

On a related note: my fake-worm fs uses relatively small
blocks (4Kb). Can I freely choose a block size for the
venti underlying the fossil, or should there be
a strict relation between the fake-worm  block size
and the fossil/venti block size (e.g. due to transfer
of dump blocks)?

Thanks for any insight (pointers welcome),
Axel.

> The new 4th edition file server, named Fossil,
> is now available on sources.  There are some
> how-to docs for setting up Venti and Fossil at:
[snip] 
> It is still a work in progress, but it's ready to be used
> by those feeling adventurous.

Re: [9fans] 4th edition file server available

[andrey mirtchovski]

will you put a link to it on http://plan9.bell-labs.com/sys/doc/index.html
(the index page for Volume 2 documents) or it's not yet supposed to be
read by third parties?

thanx, andrey

On Wed, 8 Jan 2003, Russ Cox wrote:

> The man pages fossil(4) and fossilcons(8) are
> the definitive reference.  /sys/doc/fossil.pdf (aka
> http://plan9.bell-labs.com/sys/doc/fossil.pdf)

Re: [9fans] 4th edition file server available

[Russ Cox]

> will you put a link to it on http://plan9.bell-labs.com/sys/doc/index.html
> (the index page for Volume 2 documents) or it's not yet supposed to be
> read by third parties?

I'm not sure it's quite ready for that.

Re: [9fans] 4th edition file server available

[Andrew]

Maybe this is in the doc's somewhere, but just do i know ahead of time,
does fossil have support for worm devices, ie HP optical jukeboxes and
such? thanks

Andrew

Re: [9fans] 4th edition file server available

[Russ Cox]

There is no support for WORM devices.
The WORM is replaced by Venti.  You could
back up Venti to a WORM drive, I suppose.

Re: [9fans] 4th edition file server available

[Fco.J.Ballesteros]

> You could
> back up Venti to a WORM drive, I suppose.

An alternate way would be to use fs(3) to setup a mirror
for your venti.

Re: [9fans] 4th edition file server available

[Axel Belinfante]

/sys/doc/fossil.pdf mentions an ``experimental file stack device'' devfs(3).
I'm just curious; is that man page available?
(could not find on plan9 web nor on sources)

Axel.

[9fans] Fossil questions

[John Packer]

Yesterday, for unknown reasons, I began having problems with
my fossil partition. Stupidly, I didn't have the most recent
vac score from the file server console. Using a score I saved
a couple of days ago, I was able to reformat the partition to
an earlier state (and so "lost" two days of archival
snapshots, etc.).

Suppose I didn't have a score at all. Is there some way to
recover the most recent score, perhaps from the venti server?

Also, though it's no big loss, is everything stored on Venti
in the last two days inaccessible?

Forgive me if this is addressed in the man pages.

John Packer

Re: [9fans] Fossil questions

[Russ Cox]

> Suppose I didn't have a score at all. Is there some way to
> recover the most recent score, perhaps from the venti server?

Yes.  Since the data is not encrypted, if you have access to
the raw disk partitions storing the arenas, you can find
anything you want.

> Also, though it's no big loss, is everything stored on Venti
> in the last two days inaccessible?

Do a pull to get the new file /sys/src/cmd/venti/printarena.c
and then

	cd /sys/src/cmd/venti
	mk 8.printarena

Then, run this on the Venti server as the host owner:

cd /sys/src/cmd/venti
ventihttp=your-server:8000
hget http://$ventihttp/index | 
awk '
 /^index=/ { blockSize=0+substr($3, 11); }
 /^arena=/ { arena=substr($1, 7); }
 /^	arena=/ { start=0+substr($5, 2)-blockSize; printf("./8.printarena -o %d %s\n", start, $3); }' |
rc |
sed -n 's/^(.*) 1$/vac:\1/p'

to get a list of all the vac archives on the server.

Russ

Re: [9fans] Fossil questions

[John Packer]

Thanks for your help, Russ. That worked nicely.

John Packer


On Tuesday, January 28, 2003, at 09:02  PM, Russ Cox wrote:

>> Suppose I didn't have a score at all. Is there some way to
>> recover the most recent score, perhaps from the venti server?
>
> Yes.  Since the data is not encrypted, if you have access to
> the raw disk partitions storing the arenas, you can find
> anything you want.
>
>> Also, though it's no big loss, is everything stored on Venti
>> in the last two days inaccessible?
>
> Do a pull to get the new file /sys/src/cmd/venti/printarena.c
> and then
>
> 	cd /sys/src/cmd/venti
> 	mk 8.printarena
>
> Then, run this on the Venti server as the host owner:
>
> cd /sys/src/cmd/venti
> ventihttp=your-server:8000
> hget http://$ventihttp/index |
> awk '
>  /^index=/ { blockSize=0+substr($3, 11); }
>  /^arena=/ { arena=substr($1, 7); }
>  /^	arena=/ { start=0+substr($5, 2)-blockSize; printf("./8.printarena 
> -o %d %s\n", start, $3); }' |
> rc |
> sed -n 's/^(.*) 1$/vac:\1/p'
>
> to get a list of all the vac archives on the server.
>
> Russ

Re: [9fans] Fossil questions

[Tharaneedharan Vilwanathan]

Hi,

I was also wondering what happens in this kind of situatation (i.e. when one
forgets the fingerprint value). This utility very useful.

The other question I had is what happens if I terminate a vac command
abruptly? Is it that the blocks (that are written till that time) are there
somewhere permanently but one cannot get them out? Or is it that some level
of clean up is done?

Regards
dharani

> Thanks for your help, Russ. That worked nicely.
>
> John Packer
>
>
> On Tuesday, January 28, 2003, at 09:02  PM, Russ Cox wrote:
>
> >> Suppose I didn't have a score at all. Is there some way to
> >> recover the most recent score, perhaps from the venti server?
> >
> > Yes.  Since the data is not encrypted, if you have access to
> > the raw disk partitions storing the arenas, you can find
> > anything you want.
> >
> >> Also, though it's no big loss, is everything stored on Venti
> >> in the last two days inaccessible?
> >
> > Do a pull to get the new file /sys/src/cmd/venti/printarena.c
> > and then
> >
> > cd /sys/src/cmd/venti
> > mk 8.printarena
> >
> > Then, run this on the Venti server as the host owner:
> >
> > cd /sys/src/cmd/venti
> > ventihttp=your-server:8000
> > hget http://$ventihttp/index |
> > awk '
> >  /^index=/ { blockSize=0+substr($3, 11); }
> >  /^arena=/ { arena=substr($1, 7); }
> >  /^ arena=/ { start=0+substr($5, 2)-blockSize; printf("./8.printarena
> > -o %d %s\n", start, $3); }' |
> > rc |
> > sed -n 's/^(.*) 1$/vac:\1/p'
> >
> > to get a list of all the vac archives on the server.
> >
> > Russ
>

Re: [9fans] Fossil questions

[Russ Cox]

When you interrupt a vac, the blocks are there
permanently and you can get them out if you know
their hashes, but of course you don't.  However,
if you store the same blocks again (you restart the
vac) they won't be stored a second time.

Russ

Re: [9fans] 4th edition file server available

[Skip Tavakkolian]

> there are numerous other improvements,
> including enormous file names
> g% x=`{perl -e 'print "a"x2000'}
> g% >$x
> g% ls -l $x

This is a new challenge to people coming up with class names (and depth)
for Java.

Re: [9fans] 4th edition file server available

[okamoto]

> there are many other differences.  It is a user-level
> program rather than a special kernel, it speaks 9P2000
> (and not 9P1), and there are numerous other improvements,
> including enormous file names and also soft updates so that
> the disk image is always in a consistent state.

Does this mean we don't need il protocol anymore?

Kenji

Re: [9fans] 4th edition file server available

[Russ Cox]

> Does this mean we don't need il protocol anymore?

Correct.

Re: [9fans] 4th edition file server available

[rog]

> /sys/doc/fossil.pdf mentions an ``experimental file stack device'' devfs(3).
> I'm just curious; is that man page available?
> (could not find on plan9 web nor on sources)

it's a mistake in the paper.
see instead fs(3).

Re: [9fans] 4th edition file server available

[Russ Cox]

the credit for fs(3) goes to nemo, by the way.

[9fans] 4th edition file server available

[Joel Salomon]

>It is a user-level program rather than a special kernel
One advantage (as I understood it) of using a specialized kernel was a form of security -- there were *no* user mode programs whose bugs could be exploited. How "standalone" can a Fossil/Venti server be? Can I delete almost everything in /bin to "lock down" the system?

--Joel



_______________________________________________
Join Excite! - http://www.excite.com
The most personalized portal on the Web!

Re: [9fans] 4th edition file server available

[jmk]

On Sat Jan 11 21:37:18 EST 2003, joelcsalomon@excite.com wrote:
> 
> >It is a user-level program rather than a special kernel
> One advantage (as I understood it) of using a specialized kernel was a form of security -- there were *no* user mode programs whose bugs could be exploited. How "standalone" can a Fossil/Venti server be? Can I delete almost everything in /bin to "lock down" the system?
> 
> --Joel

The intent is that it should be possible to configure the system
via the kernel config such that the only process(es) running are
those necessary to run a fileserver, i.e. fossil and factotum, with
only a physical console for control. The less paranoid you are, the
more user level stuff you can leave running, e.g. starting fossil
from /bin/cpurc.

Of course, we're nowhere near there yet.

--jim

Re: [9fans] 4th edition file server available

[Richard Miller]

> One advantage (as I understood it) of using a specialized kernel
> was a form of security -- there were *no* user mode programs
> whose bugs could be exploited.

It went further than that: you couldn't even exploit a buffer overflow
to exec a shell, because there was no shell and no exec.

Would it be feasible, as part of bootstrapping a minimal fossil
server, to remove or otherwise disable the exec system call
once everything was running?

-- Richard

Re: [9fans] 4th edition file server available

[Russ Cox]

> Would it be feasible, as part of bootstrapping a minimal fossil
> server, to remove or otherwise disable the exec system call
> once everything was running?

Of course.  Go ahead if you really want.  I don't want to live
in that environment.  There are no buffer overflows anyway.  ;-)
I _really_ like the fact that I can run other programs on
the file server now, like flchk.  I'm not going back.

I think it's reasonable not to run any services on the
machine other than fossil, and to connect with a serial
console to run other things.  Disabling exec strikes me
as extreme.

Re: [9fans] 4th edition file server available

[andrey mirtchovski]

On Mon, 13 Jan 2003, Russ Cox wrote:

> There are no buffer overflows anyway.  ;-)


I see the smiley, but have to reply anyway. this is not a nasty jab
at Russ, just a fix (I hope :)

there's a buffer overflow in cpu.c (strcpy):

% cpu -h `{perl -e '{print "A"x100;}'}
cpu 116986: suicide: sys: trap: fault read addr=0x19000 pc=0x00005b8b
plan9% acid 116986
/proc/116986/text:386 plan 9 executable

/sys/lib/acid/port
/sys/lib/acid/386
acid: stk()
At pc:0x00005b8b:fmtfmt+0x1f /sys/src/libc/fmt/fmt.c:63
fmtfmt(c=0x00000073) /sys/src/libc/fmt/fmt.c:57
        called from _fmtdispatch+0x83 /sys/src/libc/fmt/fmt.c:175
_fmtdispatch(isrunes=0x00000000,f=0x7fffeb48,fmt=0x000168b6) /sys/src/libc/fmt/fmt.c:113
        called from dofmt+0x75 /sys/src/libc/fmt/dofmt.c:62
dofmt(fmt=0x000168b4,f=0x7fffeb48) /sys/src/libc/fmt/dofmt.c:7
        called from vsnprint+0x62 /sys/src/libc/fmt/vsnprint.c:20
vsnprint(len=0x00000100,buf=0x00018734,args=0x7fffebac,fmt=0x000168b0) /sys/src/libc/fmt/vsnprint.c:5
        called from snprint+0x2b /sys/src/libc/fmt/snprint.c:13
snprint(fmt=0x000168b0,buf=0x00018734,len=0x00000100) /sys/src/libc/fmt/snprint.c:5
        called from netmkaddr+0x5e /sys/src/libc/port/netmkaddr.c:34
netmkaddr(linear=0x00017e0c,defnet=0x00000000,defsrv=0x00016978) /sys/src/libc/port/netmkaddr.c:10
        called from rexcall+0x28 /sys/src/cmd/cpu.c:347
rexcall(host=0x00017e0c,service=0x00016978,fd=0x7fffed98) /sys/src/cmd/cpu.c:339
        called from main+0x132 /sys/src/cmd/cpu.c:147
main(argv=0x7fffef84,argc=0x00000000) /sys/src/cmd/cpu.c:77
        called from _main+0x31 /sys/src/libc/386/main9.s:16
acid:


----------------------

here's the fix:

plan9% diff cpu.c /sys/src/cmd/cpu.c
121c121
<               strncpy(system, p, sizeof system);
---
>               strcpy(system, p);
plan9% 8c cpu.c; 8l cpu.8
plan9% 8.out -h `{perl -e '{print "A"x100}'}
cpu: can't dial: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA: cs: can't translate address
plan9%

Re: [9fans] 4th edition file server available

[Scott Schwartz]

Andrey writes:
| <               strncpy(system, p, sizeof system);

That still has the problem that strncpy is not required to NUL terminate
the destination.  How about strecpy?

Re: [9fans] 4th edition file server available

[andrey mirtchovski]

I agree, this opens up a whole new can of worms, as illustrated here:

Miller, T. C., Raadt, T. D.
strlcpy and strlcat -- Consistent, Safe, String Copy and Concatenation.
Proceedings of USENIX Annual Technical Conference. June,
1999. http://www.openbsd.org/papers/strlcpy-paper.ps

on the other hand I think we're in the unique position to fix strncpy
instead of adding another syscall -- after all it's not Ken C we're
dealing with :)

andrey

On Tue, 14 Jan 2003, Scott Schwartz wrote:

> Andrey writes:
> | <               strncpy(system, p, sizeof system);
>
> That still has the problem that strncpy is not required to NUL terminate
> the destination.  How about strecpy?
>

Re: [9fans] 4th edition file server available

[andrey mirtchovski]

or, we can just avoid it altogether...

s/Ken C/ANSI C/ in the previous email

andrey

Re: [9fans] 4th edition file server available

[Russ Cox]

> Miller, T. C., Raadt, T. D.
> strlcpy and strlcat -- Consistent, Safe, String Copy and Concatenation.
> Proceedings of USENIX Annual Technical Conference. June,
> 1999. http://www.openbsd.org/papers/strlcpy-paper.ps

surely this is near the top of the list for most trivial usenix paper ever.

> on the other hand I think we're in the unique position to fix strncpy
> instead of adding another syscall

strecpy serves a similar purpose.

we left strncat alone to avoid surprises when porting plan 9
code to other systems.

Re: [9fans] 4th edition file server available

[Douglas A. Gwyn]

Russ Cox wrote:
> we left strncat alone to avoid surprises when porting plan 9
> code to other systems.

An excellent policy, which also helps in importing software
from other systems.  Standards have a purpose.

Re: [9fans] 4th edition file server available

[Russ Cox]

> An excellent policy, which also helps in importing software
> from other systems.  Standards have a purpose.

as i wrote that, i suspected you would approve.

Re: [9fans] 4th edition file server available

[rob pike, esq.]

[-- Attachment #1: Type: text/plain, Size: 135 bytes --]

A less drastic step would be to disable network ports such as
cpu and telnet, to require people to use the console to debug.

-rob

[-- Attachment #2: Type: message/rfc822, Size: 1972 bytes --]

From: Richard Miller <miller@hamnavoe.demon.co.uk>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] 4th edition file server available
Date: Mon, 13 Jan 2003 10:01:30 0000
Message-ID: <14897aa3a24d632f340f30863deb7850@hamnavoe.demon.co.uk>

> One advantage (as I understood it) of using a specialized kernel
> was a form of security -- there were *no* user mode programs
> whose bugs could be exploited.

It went further than that: you couldn't even exploit a buffer overflow
to exec a shell, because there was no shell and no exec.

Would it be feasible, as part of bootstrapping a minimal fossil
server, to remove or otherwise disable the exec system call
once everything was running?

-- Richard

Re: [9fans] 4th edition file server available

[okamoto]

> I wonder, fossil, why so geological name?

 From a view point of geologist, I suppose fossil is not so 'geologic'
name.  ?

Kenji

Re: [9fans] 4th edition file server available

[David Presotto]

[-- Attachment #1: Type: text/plain, Size: 92 bytes --]

It has both the letters f and s in it, was in out dictionary,
and has a feel of permanence.

[-- Attachment #2: Type: message/rfc822, Size: 1415 bytes --]

From: okamoto@granite.cias.osakafu-u.ac.jp
To: 9fans@cse.psu.edu
Subject: Re: [9fans] 4th edition file server available
Date: Tue, 14 Jan 2003 15:06:04 +0900
Message-ID: <e5fcb3c136701335102b6f15dc0c2525@granite.cias.osakafu-u.ac.jp>

> I wonder, fossil, why so geological name?

 From a view point of geologist, I suppose fossil is not so 'geologic'
name.  ?

Kenji

Re: [9fans] 4th edition file server available

[Andrey S. Kukhar]

dictionary-translator said me that this is geologic 
word (e.g., in expression ``useful fossils''). 
It`s not right?

-kyxap

> From a view point of geologist, I suppose fossil is not
> so 'geologic' name.  ?
>
> Kenji

Re: [9fans] 4th edition file server available

[Skip Tavakkolian]

> It has both the letters f and s in it, was in out dictionary,
> and has a feel of permanence.

It is efficient by being skeletal?

Re: [9fans] 4th edition file server available

[Russ Cox]

g% pull
c sys/src/cmd/cpu.c
c 386/bin/cpu
g% 

g% cpu -h `{perl -e 'print "a"x1000'}
cpu: can't dial: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
 aaaaaaaaaaaaaaaaaaaaaaaaaaa: cs: can't translate address
g% 

Re: [9fans] 4th edition file server available

[Andrey S. Kukhar]

I wonder, fossil, why so geological name?

-kyxap