Created attachment 224119 [details]
/var/crash/core.txt.5 scrubbed of private information like IPs, MACs
Upgrading from 12.2-RELEASE-p4 to 13.0-RELEASE made the kernel crash minutes after boot if /etc/sysctl.conf contained the line "net.link.ether.ipfw=1". No ipfw rule has a layer2 clause. Before the kernel panic there may be several SIGSEGV's of other processes.
I can confirm that I have seen this behaviour too (disabling net.link.ether.ipfw fixes this) - I didn't get a coredump though so was hard to debug.
not sure if it's helpful but... i tried enabling net.link.ether.ipfw=1 a few minutes after things had booted and settled which caused my networking to stop after about 20-30 seconds, and bge0 to watchdog timeout and reset repeatedly (never recovering until a reboot)
My setup is a HP Microserver Gen8 using the onboard bge0/1 NICs, generic kernel, ipfw (with nat), pppoe on bge1.
I tried to enable it on my notebook with 14.0-CURRENT, it doesn't panic, but something bad happened - XFCE partially hanged. I'll try to debug this at this weekend.