why would i get "Out of memory" error in a sandbox build?

[Robert P. J. Day]

  playing around with an absolutely generic sandbox build and i ran
into the following issue. i built sandbox on my fedora rawhide system
with no customization whatsoever, and executed it with no root
privilege, so i definitely expected some things not to work. i got the
following:

$ ./barebox


barebox 2014.06.0-00365-g96c53b1 #1 Wed Jul 2 15:03:37 EDT 2014


Board: barebox sandbox
could not open /dev/net/tun: Permission denied
tap tap0: probe failed: Operation not permitted
malloc space: 0x7f249f5e9010 -> 0x7f249fde900f (size 8 MiB)
environment load /dev/env0: No such file or directory
Maybe you have to create the partition.
no valid environment found on /dev/env0. Using default environment
running /env/bin/init...
\nHit any key to stop autoboot:  0
booting net
ifup: Cannot find device eth0
ifup: No such file or directory
running automount command 'ifup eth0 && mount -t tftp $eth0.serverip
/mnt/tftp' failed
ifup: Cannot find device eth0
ifup: No such file or directory
running automount command 'ifup eth0 && mount -t tftp $eth0.serverip
/mnt/tftp' failed
could not open /mnt/tftp/none-linux-barebox: No such file or directory
Booting net failed: No such file or directory
booting net failed: No such file or directory
boot: No such file or directory
barebox at barebox sandbox:/

  i'm actually good with this, it's about what i expected since i set
no environment or networking, etc.  but just for fun, i "cd"ed down
into /mnt/tftp, knowing this shouldn't work, and here's what happened:

barebox at barebox sandbox:/ cd /mnt/tftp
ifup: Cannot find device eth0
ifup: No such file or directory
running automount command 'ifup eth0 && mount -t tftp $eth0.serverip
/mnt/tftp' failed
barebox at barebox sandbox:/mnt/tftp cd /
ERROR: out of memory

no stack data available
[rpjday at localhost barebox_build]$

  in short, "cd"ing into /mnt/tftp failed as it should have, but just
trying to "cd" back to the root caused the "out of memory" error. it
seems entirely reproducible. should i have expected this?

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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