Bug#1021244: keepalived: track_script directive ignored when using vrrp_sync_group

[Daniele Palumbo]

Package: keepalived
Version: 1:2.1.5-0.2+deb11u1
Severity: important
Tags: patch upstream

Dear Maintainer,

Starting from Keepalived version 2.1.5, there is a bug which ignore the unweighted track_script, if a vrrp_sync_group is in use.

In example, with the following vrrp_instance (sample, among many)
```
vrrp_instance VI_eth0.1220 {
[...]
track_script {
chk_ping_eth0.1220
chk_bird
}
}
```

keepalived is able to properly run, but if the following snippet is added:
```
vrrp_sync_group link_instances {
group {
VI_eth0.1220
VI_eth0.1221
[...]
}
}
```

Then the following errors kicks in:
```
Warning - script chk_ping_eth0.1220 is not used
Warning - script chk_bird is not used
```

This has been acknowledge and resolved upstream:
https://github.com/acassen/keepalived/issues/1813
https://github.com/acassen/keepalived/commit/459fc2b97254f388a85fb4af41c2a020c19de657

The patch is appliacable nicely on the current debian sources, and i was able to build the package and test it out.
The regression is resolved with the above patch.

-- System Information:
Debian Release: 11.5
APT prefers stable-updates
APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'proposed-updates'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 5.10.0-8-amd64 (SMP w/1 CPU thread)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages keepalived depends on:
ii init-system-helpers 1.60
ii iproute2 5.10.0-4
ii libc6 2.31-13+deb11u4
ii libglib2.0-0 2.66.8-1
ii libmnl0 1.0.4-3
ii libnftnl11 1.1.9-1
ii libnl-3-200 3.4.0-1+b1
ii libnl-genl-3-200 3.4.0-1+b1
ii libpcre2-8-0 10.36-2+deb11u1
ii libsnmp40 5.9+dfsg-4+deb11u1
ii libssl1.1 1.1.1n-0+deb11u3

Versions of packages keepalived recommends:
ii ipvsadm 1:1.31-1+b1

keepalived suggests no packages.

-- no debconf information