selftests: net: check multicast group user count

Extend the RTM_GETMULTICAST dump test to verify IFA_MC_USERS for both
IPv4 and IPv6 multicast groups.

Run each protocol test in a fresh network namespace to avoid changing
host-network state or racing with unrelated multicast users. Join a
fixed multicast group twice using separate sockets and check that the
reported user count increases by two.

Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20260630110207.37841-4-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Yuyang Huang 2026-06-30 20:02:07 +09:00 • committed by Paolo Abeni
commit 3373cb099e