first (?) bird 3.0.0 bug report

[Alarig Le Lay]

Hello Maria,

I thought that I had the same bug, but it seems that it’s a different
one as I applied the patch but I still got a segfault at startup.

[342115.227497] bird[19396]: segfault at 8 ip 00005642c37062db sp 00007fc784295ca0 error 4 in bird[5642c366e000+f0000]
[342115.227524] Code: 39 10 0f 85 e3 8c f6 ff 48 8b 90 b0 01 00 00 8b 8a 10 01 00 00 89 4c 24 24 85 c9 0f 84 d6 00 00 00 4d 85 ff 0f 84 e0 00 00 00 <41> 0f b6 44 24 08 89 c2 83 e2 01 4d 85 ed 75 15 83 c8 01 41 88 44

I can generate a coredump and share my configuration if needed.

Alarig

On Thu 19 Dec 2024 16:14:18 GMT, Radu Anghel via Bird-users wrote:
> Hi Maria,
> 
> I tried the patch and I can confirm that it is now safe to kill and 
> revive the bird :)
> 
> Thank you!
> 
> Best,
> 
> Radu
> 
> 
> On 19.12.2024 13:38, Maria Matejka wrote:
> > Hello Radu,
> > 
> > sorry, this was a stupid omission of a null check. Fixed in 
> > b6caccfd45fb639b6dd3a8d140d3c5ba4cc79311 <https://gitlab.nic.cz/labs/ 
> > bird/-/tree/b6caccfd45fb639b6dd3a8d140d3c5ba4cc79311>. Could you please 
> > check that it works on your side now?
> > 
> > Thanks,
> > Maria
> > 
> > On Wed, Dec 18, 2024 at 02:55:19PM +0100, Maria Matejka via Bird-users 
> > wrote:
> > 
> >     We apparently missed this case in our test scenarios, so we’ll add
> >     one and check if it reproduces. We’ll ask for more info if we need it.
> > 
> >     Congratulations to the first BIRD 3 bugreport and thanks for it!
> > 
> >     On 18 December 2024 14:27:44 CET, Radu Anghel via Bird-users bird-
> >     users at network.cz <mailto:bird-users at network.cz> wrote:
> > 
> >         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; }; }|
> > 
> > –
> > Maria Matejka (she/her) | BIRD Team Leader | CZ.NIC, z.s.p.o.
> > 
>