Done. It seems like it didn't actually install, but I don't want to fiddle with it because I might get a different error.
root@OpenWrt:~# mount
rootfs on / type rootfs (rw)
/dev/root on /rom type squashfs (ro,relatime)
proc on /proc type proc (rw,noatime)
sysfs on /sys type sysfs (rw,noatime)
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noatime)
tmpfs on /dev type tmpfs (rw,noatime,size=512k,mode=755)
devpts on /dev/pts type devpts (rw,noatime,mode=600)
/dev/mtdblock3 on /overlay type jffs2 (rw,noatime)
overlayfs:/overlay on / type overlayfs (rw,relatime,lowerdir=/,upperdir=/overlay)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
/dev/sda1 on /mnt/usb type vfat (rw,noatime,fmask=0000,dmask=0000,allow_utime=0022,codepage=cp437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
/dev/loop0 on /mnt/ext type ext4 (rw,relatime,user_xattr,barrier=1,data=ordered)
none on /proc/bus/usb type usbfs (rw,relatime)
root@OpenWrt:~# ls -la /mnt/
root@OpenWrt:~# mount
rootfs on / type rootfs (rw)
/dev/root on /rom type squashfs (ro,relatime)
proc on /proc type proc (rw,noatime)
sysfs on /sys type sysfs (rw,noatime)
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noatime)
tmpfs on /dev type tmpfs (rw,noatime,size=512k,mode=755)
devpts on /dev/pts type devpts (rw,noatime,mode=600)
/dev/mtdblock3 on /overlay type jffs2 (rw,noatime)
overlayfs:/overlay on / type overlayfs (rw,relatime,lowerdir=/,upperdir=/overlay)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
/dev/sda1 on /mnt/usb type vfat (rw,noatime,fmask=0000,dmask=0000,allow_utime=0022,codepage=cp437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
/dev/loop0 on /mnt/ext type ext4 (rw,relatime,user_xattr,barrier=1,data=ordered)
none on /proc/bus/usb type usbfs (rw,relatime)
root@OpenWrt:~# ls -la /mnt/
drwxr-xr-x 1 root root 0 Jan 1 00:00 .
drwxr-xr-x 1 root root 0 Jan 1 00:00 ..
drwxr-xr-x 6 root root 1024 Jan 1 00:01 ext
drwxrwxrwx 4 root root 16384 Jan 1 00:00 usb
root@OpenWrt:~# ls -la /mnt/usb/PirateBox
ls: /mnt/usb/PirateBox: No such file or directory
root@OpenWrt:~# ls -la /mnt/usb/
external_fs/
install/
openwrt-ar71xx-generic-tl-mr3020-v1-squashfs-factory.bin
root@OpenWrt:~# cat /etc/config/network
config interface 'loopback'
option ifname 'lo'
option proto 'static'
option ipaddr '127.0.0.1'
option netmask '255.0.0.0'
config interface 'lan'
option ifname 'eth0'
option type 'bridge'
option proto 'static'
option ipaddr '192.168.1.1'
option netmask '255.255.255.0'
root@OpenWrt:~# cat /etc/config/wireless
config wifi-device radio0
option type mac80211
option channel 11
option hwmode 11ng
option macaddr 64:66:b3:ce:be:a6
option htmode HT20
list ht_capab SHORT-GI-20
list ht_capab SHORT-GI-40
list ht_capab RX-STBC1
list ht_capab DSSS_CCK-40
# REMOVE THIS LINE TO ENABLE WIFI:
option disabled 1
config wifi-iface
option device radio0
option network lan
option mode ap
option ssid OpenWrt
option encryption none
root@OpenWrt:~# dmesg | tail -n 20
[ 30.820000] cfg80211: (57240000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 4000 mBm), (N/A)
[ 31.270000] loop: module loaded
[ 31.320000] ip_tables: (C) 2000-2006 Netfilter Core Team
[ 31.490000] nf_conntrack version 0.5.0 (455 buckets, 1820 max)
[ 31.720000] ip6_tables: (C) 2000-2006 Netfilter Core Team
[ 32.000000] batman_adv: B.A.T.M.A.N. advanced 2013.4.0 (compatibility version 14) loaded
[ 35.160000] EXT4-fs (loop0): couldn't mount as ext3 due to feature incompatibilities
[ 35.170000] EXT4-fs (loop0): couldn't mount as ext2 due to feature incompatibilities
[ 35.230000] EXT4-fs (loop0): recovery complete
[ 35.230000] EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null)
[ 36.870000] ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 36.880000] device eth0 entered promiscuous mode
[ 36.880000] ADDRCONF(NETDEV_UP): br-lan: link is not ready
[ 37.650000] eth0: link up (100Mbps/Full duplex)
[ 37.650000] br-lan: port 1(eth0) entered forwarding state
[ 37.660000] br-lan: port 1(eth0) entered forwarding state
[ 37.660000] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 37.670000] ADDRCONF(NETDEV_CHANGE): br-lan: link becomes ready
[ 39.660000] br-lan: port 1(eth0) entered forwarding state
[ 43.200000] Adding 32764k swap on /mnt/usb/external_fs/OpenWRT.swap. Priority:-1 extents:1 across:32764k
root@OpenWrt:~# dmesg | grep sda
[ 10.390000] sd 0:0:0:0: [sda] 62517248 512-byte logical blocks: (32.0 GB/29.8 GiB)
[ 10.390000] sd 0:0:0:0: [sda] Write Protect is off
[ 10.400000] sd 0:0:0:0: [sda] Mode Sense: 23 00 00 00
[ 10.400000] sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 10.470000] sda: sda1
[ 10.480000] sd 0:0:0:0: [sda] Attached SCSI removable disk
root@OpenWrt:~# ls /dev/sd*
/dev/sda /dev/sda1
root@OpenWrt:~# ps
PID USER VSZ STAT COMMAND
1 root 1504 S init
2 root 0 SW [kthreadd]
3 root 0 SW [ksoftirqd/0]
4 root 0 SW [kworker/0:0]
5 root 0 SW [kworker/u:0]
6 root 0 SW< [khelper]
7 root 0 SW [kworker/u:1]
63 root 0 SW [sync_supers]
65 root 0 SW [bdi-default]
67 root 0 SW< [kblockd]
96 root 0 SW [kswapd0]
144 root 0 SW [fsnotify_mark]
173 root 0 SW< [ath79-spi]
184 root 0 SW [mtdblock0]
189 root 0 SW [mtdblock1]
194 root 0 SW [mtdblock2]
199 root 0 SW [mtdblock3]
204 root 0 SW [mtdblock4]
209 root 0 SW [mtdblock5]
250 root 0 SW [kworker/0:1]
442 root 0 SWN [jffs2_gcd_mtd3]
472 root 0 SW [khubd]
481 root 0 SW [scsi_eh_0]
482 root 0 SW [usb-storage]
505 root 1536 S {rcS} /bin/sh /etc/init.d/rcS S boot
506 root 1504 S init
507 root 1536 S {rcS} /bin/sh /etc/init.d/rcS S boot
508 root 1496 S logger -s -p 6 -t sysinit
539 root 0 SW< [cfg80211]
615 root 0 SW< [bat_events]
642 root 1508 S /sbin/syslogd -C16
644 root 1488 S /sbin/klogd
646 root 872 S /sbin/hotplug2 --override --persistent --set-rules-file /etc/hotplug2.rules --set-cold
654 root 872 S /sbin/ubusd
729 root 0 DW< [loop0]
734 root 0 DW [jbd2/loop0-8]
735 root 0 SW< [ext4-dio-unwrit]
741 root 1468 S /sbin/netifd
921 root 0 SW [flush-8:0]
923 root 0 DW [flush-7:0]
1214 root 1152 S /usr/sbin/dropbear -P /var/run/dropbear.1.pid -p 22
1341 root 1500 S /sbin/watchdog -t 5 /dev/watchdog
1405 nobody 956 S /usr/sbin/dnsmasq -C /var/etc/dnsmasq.conf
1407 root 1540 S {S95done} /bin/sh /etc/rc.common /etc/rc.d/S95done boot
1408 root 1496 S sh /etc/rc.local
1409 root 1500 S {box_installer_s} /bin/sh /bin/box_installer_start.sh
1411 root 1492 S syslogd -n -L -R 192.168.1.2:9999
1412 root 1512 S {box_installer.s} /bin/sh /bin/box_installer.sh
1413 root 1496 S logger
1431 root 3672 D opkg --cache /mnt/usb/install/cache -d ext install extendRoot-piratebox piratebox-mod-
1519 root 3732 S opkg --cache /mnt/usb/install/cache -d ext install extendRoot-piratebox piratebox-mod-
1520 root 3732 S opkg --cache /mnt/usb/install/cache -d ext install extendRoot-piratebox piratebox-mod-
1521 root 1220 R /usr/sbin/dropbear -P /var/run/dropbear.1.pid -p 22
1522 root 1520 S -ash
1561 root 1496 R ps
root@OpenWrt:~# cat /mnt/usb/install.log
cat: can't open '/mnt/usb/install.log': No such file or directory
root@OpenWrt:~#