Chrooting an emulated binary?

["C. Bensend" <benny@bennyvision.com>]

Hey folks,

	I have set up linux emulation on 3.3-STABLE as of May 23rd.  It
works perfectly - my Neverwinter Nights server comes up just fine.  Yes,
I'm an addict.  :)

	However, since this machine is going out into the untamed wilderness
eventually, I'd like to be able to chroot the server.  I don't run it
unattended (only when we fire up a gaming night), and I know that since there
are shells in /usr/local/emul/redhat the point is mostly moot.  I'm aware
that there isn't a lot of benefit.  It's become more of a "I wonder if I can"
sort of thing.

	So, using chrootuid from the ports tree, I try to fire it up:

chrootuid /usr/local/emul/redhat nwn /home/nwn/start-nwn
Segmentation fault

	'start-nwn' is just a simple sh script that sets all my options
before firing up the server.  OK, so I get a segfault.  Taking a look at
the ktrace (only the last few lines shown, full dump on request):

  3777 chrootuid NAMI  "/home/nwn/start-nwn"
  3777 chrootuid NAMI  "/bin/sh"
  3777 chrootuid NAMI  "/emul/svr4/lib/ld-linux.so.2"
  3777 chrootuid NAMI  "/emul/linux/lib/ld-linux.so.2"
  3777 bash     NAMI  "/lib/ld-linux.so.2"
  3777 bash     EMUL  "native"
  3777 bash     RET   execve 0
  3777 bash     CALL  getuid
  3777 bash     RET   getuid 1009/0x3f1
  3777 bash     CALL  getgid
  3777 bash     RET   getgid 1009/0x3f1
  3777 bash     CALL  getlogin(0x480a28cc,0xcfbfd414)
  3777 bash     RET   getlogin 0
  3777 bash     CALL  setlogin(0x480a28cc)
  3777 bash     RET   setlogin -1 errno 1 Operation not permitted
  3777 bash     CALL  ktrace(0xcfbfd1e4,0x4809b7f0,0,0x480a28cc)
  3777 bash     RET   ktrace -1 errno 2 No such file or directory
  3777 bash     PSIG  SIGSEGV SIG_DFL code 1 addr=0x0 trapno=1
  3777 bash     PSIG  SIGSEGV SIG_DFL code 0 addr=0x0 trapno=0
  3777 bash     NAMI  "bash.core"

	Could someone a little more familiar with chroot processes and/or
linux emulation interpret the last dozen or so lines?  I understand that
it's bash that's dying (the user nwn's shell), but I'm not really sure
why.  Limitation of the bash in the linux stuff, perhaps?

	Running the start-nwn script as user nwn non-chrooted works fine.

Thanks for any tips/tricks/cluebats,

Benny


-- 

God is dead and I don't feel all too well either.... -- Ralph Moonen