Panic (Fatal trap 12: page fault while in kernel mode) while playing with pf and netif names

[Rumko]

Not quite sure if the problem is in either of the two aforementioned acts or in
the combination, but while doing that (with netif names I'm thinking
of "ifconfig some_netif name new_name") I was able to panic the machine.

After getting "kernel: Non-unique normal route, mask not entered" in the dmesg
(immediatelly after loading my custom pf.conf - do note, that it does not
happen all the time, loaded the rules quite a few times to get this message),
I loaded my pf.conf again (pfctl -f /etc/pf.conf) and the machine fortunately
panicked for me (in the previous two instances of this problem, the machine
hanged and was completely unresponsive ... to ping, serial console, everything
was dead).

The dump is located at leaf:~rumko/crash/pf/ and the backtrace is:
#0  dumpsys () at ./machine/thread.h:83
#1  0xc0209e2d in boot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:378
#2  0xc020a0f2 in panic (fmt=0xc0403d38 "%s")
at /usr/src/sys/kern/kern_shutdown.c:813
#3  0xc03d29f6 in trap_fatal (frame=0xddf26770, eva=<value optimized out>)
at /usr/src/sys/platform/pc32/i386/trap.c:1093
#4  0xc03d2b30 in trap_pfault (frame=0xddf26770, usermode=0, eva=305406860)
at /usr/src/sys/platform/pc32/i386/trap.c:994
#5  0xc03d314e in trap (frame=0xddf26770)
at /usr/src/sys/platform/pc32/i386/trap.c:674
#6  0xc03bd927 in calltrap ()
at /usr/src/sys/platform/pc32/i386/exception.s:785
#7  0xc02a3d21 in rn_walktree (h=0xc39f9080, f=0xc029d5db <pfr_walktree>,
w=0xddf267e0) at /usr/src/sys/net/radix.c:996
#8  0xc029bbe4 in pfr_mark_addrs (kt=0xdddf3c00)
at /usr/src/sys/net/pf/pf_table.c:723
#9  0xc029f1c1 in pfr_commit_ktable (kt=0xdddf3c00, tzero=1255984339)
at /usr/src/sys/net/pf/pf_table.c:1596
#10 0xc029f44a in pfr_ina_commit (trs=0xddf26a18, ticket=4, nadd=0x0,
nchange=0x0, flags=<value optimized out>)
at /usr/src/sys/net/pf/pf_table.c:1566
#11 0xc029792d in pfioctl (ap=0xddf26b8c)
at /usr/src/sys/net/pf/pf_ioctl.c:2669
#12 0xc01f05fe in dev_dioctl (dev=0xc3a24b80, cmd=3222029394,
data=0xddf26c18 "\r", fflag=3, cred=0xdd8f1478, msg=0xddf26cf0)
    at /usr/src/sys/kern/kern_device.c:174
#13 0xc032e7ef in devfs_specf_ioctl (fp=0xdd3e5958, com=3222029394,
data=0xddf26c18 "\r", ucred=0xdd8f1478, msg=0xddf26cf0)
    at /usr/src/sys/vfs/devfs/devfs_vnops.c:1354
#14 0xc022d92d in mapped_ioctl (fd=3, com=3222029394, uspc_data=0xbfbff584
<Address 0xbfbff584 out of bounds>, map=0x0, msg=0xddf26cf0)
    at /usr/src/sys/sys/file2.h:88
#15 0xc022d9b6 in sys_ioctl (uap=0xddf26cf0)
at /usr/src/sys/kern/sys_generic.c:521
#16 0xc03d37a9 in syscall2 (frame=0xddf26d40)
at /usr/src/sys/platform/pc32/i386/trap.c:1339
#17 0xc03bd9d6 in Xint0x80_syscall ()
at /usr/src/sys/platform/pc32/i386/exception.s:876
#18 0x2811ac63 in ?? ()
Backtrace stopped: previous frame inner to this frame (corrupt stack?)
-- 
Regards,
Rumko