immediate reboot with ipnat/ipmon on amd64

[Michiel Boland]

Hi. Sorry about the delay.

> Do you have access to system console to confirm that it does not panic
> and just rebooted?  Looks like a panic I think...

There does indeed seem to be some kind of panic. After attaching serial 
console, I got this.

Memory modified after free 0xffffff00090da480(56) val=3f91400 @ 
0xffffff00090da498
panic: Most recently used by temp

KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2a
panic() at panic+0x17c
mtrash_ctor() at mtrash_ctor+0x84
uma_zalloc_arg() at uma_zalloc_arg+0x2cd
malloc() at malloc+0x8a
uifind() at uifind+0xa4
seteuid() at seteuid+0x49
syscall() at syscall+0x1ce
Xfast_syscall() at Xfast_syscall+0xab
--- syscall (183, FreeBSD ELF64, seteuid), rip = 0x8009b817c, rsp = 
0x7fffffffed08, rbp = 0 ---

I'm trying to do some real work, thus I had to bin the kernel 
that crashed. So I don't have any more info at the moment.