first (?) bird 3.0.0 bug report

[Radu Anghel]

Hi,

Using a slightly modified version of the config from the 2.15.1 (just 
some {} inside case structures), but probably unrelated.

If bird gets killed/not shut down properly and routes remain in the 
kernel then bird 3.0.0 is unable to restart and just segfaults when 
trying to refresh kernel routes.

I can reproduce it by just kill -9 bird && restarting bird.

daemon.debug bird: KERNEL6.ipv6: route refresh begin: rr 1 set 1 valid 0 
pruning 0 pruned 0

kern.info kernel: [75645.964935] bird[4162]: segfault at 0 ip 
000000000045d47b sp 00007ffcb9f9f2c0 error 4 in bird[403000+a8000] 
likely on CPU 1 (core 0, socket 1)

kern.info kernel: [75645.970115] Code: 5d 41 5c 41 5d 41 5e 41 5f c3 55 
53 48 89 fb 48 83 ec 38 80 bb 79 02 00 00 04 48 8b 7f 30 75 46 48 89 d5 
31 d2 e8 63 a4 ff ff <83> 38 00 49 89 c0 75 07 31 c0 e9 9d 00 00 00 48 
8b 40 10 48 8d 7b

The kernel protocol config is:

protocol kernel KERNEL6 {
     debug { events, states };
     scan time 3600;

     merge paths on;

     metric 0;
     ipv6 {
         import filter KERNEL_IN;
         export filter KERNEL_OUT;
     };
}

Cheers,

R