IPv6 VRF prefix marked as invalid by BGP after ca32945b1fd6 (regression)

[SPYFF]

Description

In one of our scenario a BGP prefix marked as invalid and not advertized after commit ca32945.
Before this commit, the prefix marked as valid and successfully advertized as well.

Version

r1# show version 
FRRouting 10.1-dev-dbg-gca32945b1 (r1) on Linux(6.8.0-52-generic).
Copyright 1996-2005 Kunihiro Ishiguro, et al.
This is a git build of frr-10.0-dev-327-gca32945b1
Associated branch(es):
	local:(HEAD detached at ca32945b1)


This is where the `git bisect` stopped.

How to reproduce

There is a reproducer, I attach the files. It has some directories, so I zip-ed them, hopefully not problem.

reproducer.zip

I used mininet emulator which is similar to topotest but focusing on interactive usage instead being part of a CI pipeline. I did not wanted to replace the installer FRR so I worked in the /tmp dir. Unpack the zip to /tmp/FRRTEST folder and install FRR to the /tmp/FRRTEST/build-dir directory. Then simply run sudo ./srv6topo-bgpdbg.py.

Also there are some debug logs. In the good.log which is before the regression, I see entries related to the 2001:abba:0:a1::/64 prefix. After the commit, in bad.log I see none of them.

bad.log
good.log

Expected behavior

If the mininet environment running ping between nodes ru1 and du1 will work:

mininet> ru1 ping 2001:be1a:0:d11::d11 -I 2001:abba:0:a11::a11
PING 2001:be1a:0:d11::d11 (2001:be1a:0:d11::d11) from 2001:abba:0:a11::a11 : 56 data bytes
64 bytes from 2001:be1a:0:d11::d11: icmp_seq=1 ttl=63 time=0.232 ms
64 bytes from 2001:be1a:0:d11::d11: icmp_seq=2 ttl=63 time=0.072 ms

mininet> ru1 ping 2001:be1a:0:d1::d1 -I 2001:abba:0:a1::a1
PING 2001:be1a:0:d1::d1 (2001:be1a:0:d1::d1) from 2001:abba:0:a1::a1 : 56 data bytes
64 bytes from 2001:be1a:0:d1::d1: icmp_seq=1 ttl=63 time=0.098 ms
64 bytes from 2001:be1a:0:d1::d1: icmp_seq=2 ttl=63 time=0.072 ms

Also BGP prefix 2001:abba:0:a1::/64 marked as valid, and advertized:

mininet> r1 vtysh -c "sh bgp vrf vrf66 all"

For address family: IPv6 VPN
BGP table version is 8, local router ID is 10.0.0.1, vrf id 0
Default local pref 100, local AS 64512
Status codes:  s suppressed, d damped, h history, u unsorted, * valid, > best, = multipath,
               i internal, r RIB-failure, S Stale, R Removed
Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
Origin codes:  i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

     Network          Next Hop            Metric LocPrf Weight Path
Route Distinguisher: 64512:66
 *>  2001:abba:0:a1::/64
                    2001:a1fa:0:1::1(detnet)@5
                                             0    120  32768 i
    UN=2001:a1fa:0:1::1 EC{64512:66} label=32 sid=2001:fade:0:1:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=5
 *>  2001:abba:0:a11::/64
                    2001:a1fa:0:1::1(detnet)@5
                                             0    110  32768 ?
    UN=2001:a1fa:0:1::1 EC{64512:66} label=32 sid=2001:fade:0:1:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=5
 *>  2001:abba:0:8a11::/64
                    2001:a1fa:0:1::1(detnet)@5
                                             0         32768 i
    UN=2001:a1fa:0:1::1 EC{64512:66} label=32 sid=2001:fade:0:1:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=5
 *>i 2001:be1a:0:d1::/64
                    2001:a1fa:0:3::3(detnet)
                                             0    120      0 i
    UN=2001:a1fa:0:3::3 EC{64512:66} label=32 sid=2001:fade:0:3:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=0
 *>i 2001:be1a:0:d11::/64
                    2001:a1fa:0:3::3(detnet)
                                             0    110      0 ?
    UN=2001:a1fa:0:3::3 EC{64512:66} label=32 sid=2001:fade:0:3:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=0
 *>i 2001:be1a:0:8d13::/64
                    2001:a1fa:0:3::3(detnet)
                                             0    100      0 i
    UN=2001:a1fa:0:3::3 EC{64512:66} label=32 sid=2001:fade:0:3:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=0

Displayed 6 routes and 6 total paths

Actual behavior

If the mininet environment running ping between nodes ru1 and du1 will work partially:

mininet> ru1 ping 2001:be1a:0:d11::d11 -I 2001:abba:0:a11::a11
PING 2001:be1a:0:d11::d11 (2001:be1a:0:d11::d11) from 2001:abba:0:a11::a11 : 56 data bytes
64 bytes from 2001:be1a:0:d11::d11: icmp_seq=1 ttl=63 time=0.232 ms
64 bytes from 2001:be1a:0:d11::d11: icmp_seq=2 ttl=63 time=0.072 ms

mininet> ru1 ping 2001:be1a:0:d1::d1 -I 2001:abba:0:a1::a1
PING 2001:be1a:0:d1::d1 (2001:be1a:0:d1::d1) from 2001:abba:0:a1::a1 : 56 data bytes
From 2001:abba:0:8a11::1 icmp_seq=1 Destination unreachable: No route
From 2001:abba:0:8a11::1 icmp_seq=2 Destination unreachable: No route

Also BGP prefix 2001:abba:0:a1::/64 marked as invalid, and not advertized:

mininet> r1 vtysh -c "sh bgp vrf vrf66 all"

For address family: IPv6 VPN
BGP table version is 4, local router ID is 10.0.0.1, vrf id 0
Default local pref 100, local AS 64512
Status codes:  s suppressed, d damped, h history, u unsorted, * valid, > best, = multipath,
               i internal, r RIB-failure, S Stale, R Removed
Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
Origin codes:  i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

     Network          Next Hop            Metric LocPrf Weight Path
Route Distinguisher: 64512:66
     2001:abba:0:a1::/64
                    2001:a1fa:0:1::1(detnet)@5
                                             0    120  32768 i
    UN=2001:a1fa:0:1::1 EC{64512:66} label=32 sid=2001:fade:0:1:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=5
 *>  2001:abba:0:a11::/64
                    2001:a1fa:0:1::1(detnet)@5
                                             0    110  32768 ?
    UN=2001:a1fa:0:1::1 EC{64512:66} label=32 sid=2001:fade:0:1:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=5
 *>  2001:abba:0:8a11::/64
                    2001:a1fa:0:1::1(detnet)@5
                                             0         32768 i
    UN=2001:a1fa:0:1::1 EC{64512:66} label=32 sid=2001:fade:0:1:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=5
 *>i 2001:be1a:0:d11::/64
                    2001:a1fa:0:3::3(detnet)
                                             0    110      0 ?
    UN=2001:a1fa:0:3::3 EC{64512:66} label=32 sid=2001:fade:0:3:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=0
 *>i 2001:be1a:0:8d13::/64
                    2001:a1fa:0:3::3(detnet)
                                             0    100      0 i
    UN=2001:a1fa:0:3::3 EC{64512:66} label=32 sid=2001:fade:0:3:8000:: sid_structure=[48,17,15,0] type=bgp, subtype=0

Displayed 5 routes and 5 total paths

Additional context

No response

Checklist

• I have searched the open issues for this bug.
• I have not included sensitive information in this report.