Better networking thanks to Ronny Kalusniok.

Updated the configuration to use Linux kernel 4.1.5.

src/.config

@@ -2,7 +2,7 @@
 #
 # http://kernel.org
 #
-KERNEL_SOURCE_URL=https://www.kernel.org/pub/linux/kernel/v4.x/linux-4.0.tar.xz
+KERNEL_SOURCE_URL=https://www.kernel.org/pub/linux/kernel/v4.x/linux-4.1.5.tar.xz
 
 # You can find the latest BusyBox source bundles here:
 #

src/5_generate_rootfs.sh

@@ -31,9 +31,10 @@ mount -t devtmpfs none /dev
 mount -t proc none /proc
 mount -t sysfs none /sys
 
-ip link set lo up
-ip link set eth0 up
-udhcpc -b -i eth0 -s /etc/rc.dhcp
+for DEVICE in /sys/class/net/* ; do
+	ip link set \${DEVICE##*/} up
+	[ \${DEVICE##*/} != lo ] && udhcpc -b -i \${DEVICE##*/} -s /etc/rc.dhcp
+done
 
 EOF
 
@@ -44,7 +45,7 @@ cat > rc.dhcp << EOF
 
 ip addr add \$ip/\$mask dev \$interface
 
-if [ -n "$router"]; then
+if [ "\$router" ]; then
   ip route add default via \$router dev \$interface
 fi