does sysinstall's "Upgrade" ever use the local system's shell?

[Royce Williams]

Question:

Does the sysinstall "Upgrade" option have a dependency on the local 
system's sh at any time during the install?

Details:

I have a system that I'm trying to rescue.  It has a mix of 
6.2-SECURITY and 6.3-BETA components due to a failure during the 
freebsd-update minor-upgrade procedure.  After some analysis and help
from cperciva, we think that this was due to possible filesystem 
errors that have since been corrected.

On Colin's recommendation, to repair the system, I am not relying on 
anything local to the system and instead, using sysinstall's "upgrade"
option from CD to upgrade 6.3-RC1.

Somewhere during or after the backup of /etc, I get this dialog:

"Hmmm!  I couldn't move the old kernel over!  Do you want to
treat this as a big problem and abort the upgrade?  Due to the
way that this upgrade process works, you will have to reboot
and start over from the beginning.  Select Yes to reboot now"


The verbose upgrade output ends here, with this error:

/mnt/stand/usbdevs
/mnt/stand/dhclient-script
4330 blocks
/libexec/ld-elf.so.1: sh: Undefined symbol "__sbmaskrune"


This is the exactly the same error that I get when trying to run the 
local system's sh.  I'm pretty sure that the sh that comes on the 
6.3-RC1 CD is OK.  Is the installUpgrade.c system(mv) call here:

          if (system("mv /boot/kernel /boot/kernel.prev")) {
		if (!msgYesNo("Hmmm!  I couldn't move the old kernel over!  Do you want to\n"
			      "treat this as a big problem and abort the upgrade?  Due to the\n"
			      "way that this upgrade process works, you will have to reboot\n"
			      "and start over from the beginning.  Select Yes to reboot now"))
		    systemShutdown(1);

... managing to invoke the local shell instead of the one on the CD?
Not knowing any better, if local binaries are being called for some
part of the upgrade, that would be a Bad Thing and I should open a PR.

Royce

-- 
Royce D. Williams                                - IP Engineering, ACS
http://www.tycho.org/royce/                   - PGP: 3FC087DB/1776A531
We are called to be architects of the future, not its victims. -Fuller