Miguel Mendez wrote:

Tim Kientzle <[EMAIL PROTECTED]> wrote:

1) Fragility.  Could a naive sysadmin (or a dying
   disk) break /[s]bin?
   What if the ldconfig hints files were hosed?
   Is ld-elf.so truly bulletproof?
Agreed, and, fortunately, that was taken into account with the
introduction of the /rescue dir:

christine: {48} du -h /rescue
2.4M    /rescue

Oh.  So the real size of NetBSD's /bin and /sbin includes
another 2.4M for /rescue.  That makes it less
impressive.  I don't find the duplication appealing, either.
(Why not just put the /rescue versions directly
into /bin and /sbin?  That would be smaller still,
wouldn't it?)

2) Security.  Can LD_LIBRARY_PATH (or other mechanisms)
   be used to deliberately subvert any of these programs?
   (especially the handful of suid/sgid programs here)

Several people have pointed out that FreeBSD has
certain protections against LD_LIBRARY_PATH exploits,
but there are still real questions here.  (Kernel
races, possibly?)  Privilege elevation is an
interesting idea, but tricky to audit.

the results from ls -l /bin on your NetBSD system

christine: {66} ls -l /bin
-r-xr-xr-x  1 root  wheel    8480 Oct 29 22:59 cat

-r-xr-xr-x  1 root  wheel    4892 Oct 29 23:00 echo
> -r-xr-xr-x  1 root  wheel    5568 Oct 29 23:01 rmdir

-r-xr-xr-x  1 root  wheel    5892 Oct 29 23:02 sleep
-r-xr-xr-x  1 root  wheel    4652 Oct 29 23:02 sync
> [[ others omitted ]]

<sigh>  I've been looking at some of the FreeBSD standard utils,
and with a very little bit of work got this:

-rwxr-xr-x  1 tim  tim  9552 Nov  4 11:10 cat
-rwxr-xr-x  1 tim  tim  2776 Nov  4 11:10 echo
-rwxr-xr-x  1 tim  tim  3288 Nov  1 13:48 rmdir
-rwxr-xr-x  1 tim  tim  2904 Nov  4 11:10 sleep
-rwxr-xr-x  1 tim  tim  2424 Nov  4 11:10 sync

All statically linked, all portable C, with identical
functionality to the originals.  If statically-linked
versions can be 1/2 the size of the dynamic versions,
then I _really_ don't see the advantage of dynamic linking.
Perhaps some more careful programming is all that's needed?  ;-)
(Admittedly, a space-conscious overhaul of sh, csh, or ed
is not entirely trivial; but most of /bin and /sbin is pretty simple
to prune down.)

rcNG has been in work for a long time. Is it worth it? Absolutely,
try it once and you'll wonder how you could live with the old system, or
even with the sysV symlink crazyness.

As it happens, I've been looking closely at RCng
just recently.  Though I really like the core design, I do
have some quibbles with the implementation.  It
is usable today, and does address the worst problems
of SysV-style init.  Still needs some work, though.  ;-)

Tim Kientzle

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