TI-RPC tests: rpc_clnt_broadcast times out all the time even with remote calls enabled

[pevik]

TI-RPC rpc_clnt_broadcast times out all the time even with remote calls enabled:

# rpc_test.sh -s rpc_svc_1 -c rpc_clnt_broadcast
rpc_test 1 TINFO: rpcbind 1.2.9
debug: yes, libset debug: yes, libwrap: yes, nss modules: files usrfiles, remote calls: yes, statedir: /run/rpcbind, systemd: yes, user: rpc, warm start: yes
rpc_test 1 TINFO: check registered RPC with rpcinfo
rpc_test 1 TINFO: registered RPC:
   program vers proto   port  service
    100000    4   tcp    111  portmapper
    100000    3   tcp    111  portmapper
    100000    2   tcp    111  portmapper
    100000    4   udp    111  portmapper
    100000    3   udp    111  portmapper
    100000    2   udp    111  portmapper
    100024    1   udp  57348  status
    100024    1   tcp  39535  status
    100005    1   udp  20048  mountd
    100005    1   tcp  20048  mountd
    100005    2   udp  20048  mountd
    100005    2   tcp  20048  mountd
    100005    3   udp  20048  mountd
    100005    3   tcp  20048  mountd
    100003    3   tcp   2049  nfs
    100003    4   tcp   2049  nfs
    100227    3   tcp   2049  nfs_acl
    100021    1   udp  40395  nlockmgr
    100021    3   udp  40395  nlockmgr
    100021    4   udp  40395  nlockmgr
    100021    1   tcp  40947  nlockmgr
    100021    3   tcp  40947  nlockmgr
    100021    4   tcp  40947  nlockmgr
rpc_test 1 TINFO: using libtirpc: yes
RPC: Timed out
rpc_test 1 TFAIL: rpc_clnt_broadcast 10.0.0.2 536875000 failed unexpectedly

Investigate the reason.

Mentioned upstream some time ago, no response:
https://lore.kernel.org/linux-nfs/20250804184850.313101-1-pvorel@suse.cz/

[pevik]

strace shows:

setsockopt(6, SOL_SOCKET, SO_BROADCAST, [1], 4) = 0
sendto(6, "jCK\10\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\3\0\0\0\5\0\0\0\1\0\0\0\34"..., 88, 0, {sa_family=AF_INET, sin_port=htons(111), sin_addr=inet_addr("10.0.0.1")}, 16) = 88
sendto(6, "jCK\t\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\2\0\0\0\5\0\0\0\1\0\0\0\34"..., 88, 0, {sa_family=AF_INET, sin_port=htons(111), sin_addr=inet_addr("10.0.0.1")}, 16) = 88
poll([{fd=6, events=POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND}], 1, 4000) = 0 (Timeout)
setsockopt(6, SOL_SOCKET, SO_BROADCAST, [1], 4) = 0
sendto(6, "jCK\10\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\3\0\0\0\5\0\0\0\1\0\0\0\34"..., 88, 0, {sa_family=AF_INET, sin_port=htons(111), sin_addr=inet_addr("10.0.0.1")}, 16) = 88
sendto(6, "jCK\t\0\0\0\0\0\0\0\2\0\1\206\240\0\0\0\2\0\0\0\5\0\0\0\1\0\0\0\34"..., 88, 0, {sa_family=AF_INET, sin_port=htons(111), sin_addr=inet_addr("10.0.0.1")}, 16) = 88
poll([{fd=6, events=POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND}], 1, 8000) = 0 (Timeout)
close(6)                                = 0
close(5)                                = 0
write(2, "RPC: Timed out\n", 15RPC: Timed out

Which points out to src/clnt_bcast.c

__rpc_broadenable(int af, int s, struct broadif *bip)
{
    if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &o, sizeof o) < 0)
        return -1;
    return 0;
}

I wonder when was the last time the code actually worked :).