udhcpc uses 100% cpu

[William Thompson]

I'm using udhcpc from an initramfs and I've noticed it's eating all the CPU
time.  Busybox v1.5.0

I decided to strace it and I'm seeing this over and over again:
sysinfo({uptime=909, loads=[71200, 63040, 36928] totalram=262553600, freeram=223490048, sharedram=0, bufferram=0} totalswap=0, freeswap=0, procs=35}) = 0
select(1, [0], NULL, NULL, {296, 0})    = 1 (in [0], left {296, 0})
sysinfo({uptime=909, loads=[71200, 63040, 36928] totalram=262553600, freeram=223490048, sharedram=0, bufferram=0} totalswap=0, freeswap=0, procs=35}) = 0
read(0, "", 4)                          = 0

According to /proc, fd 0 is /dev/null:
/: v /proc/3947/fd
total 0
lrwx------    1 root     root           64 May 23 08:41 0 -> /dev/null
lrwx------    1 root     root           64 May 23 08:41 1 -> /dev/null
lrwx------    1 root     root           64 May 23 08:41 2 -> /dev/null
lrwx------    1 root     root           64 May 23 08:41 3 -> socket:[924]
/:

I'm calling udhcpc like this: udhcpc -i eth0 -p /tmp/dhcpc.pid -n

It appears that somewhere, something is setting the fd to 0 when it should
be 3.