Assert fd validity in start_udp_child()

load_balance_sockets is fixed at netmgr init, so dup(fd) runs only when
the caller supplied a valid descriptor.  Assert it to silence a
scan-build false positive:

    lib/isc/netmgr/udp.c:194:15: warning: The 1st argument to 'dup' is -1 but should be >= 0 [unix.StdCLibraryFunctions]

Assisted-by: Claude:claude-opus-4-8

diff --git a/lib/isc/netmgr/udp.c b/lib/isc/netmgr/udp.c
index 7922683bdc91f3b742be25e4fb675abe3893c066..fa79717fb7764a75d5e77cf0d66be13bccf04b39 100644 (file)
--- a/lib/isc/netmgr/udp.c
+++ b/lib/isc/netmgr/udp.c
@@ -191,6 +191,7 @@ start_udp_child(isc_sockaddr_t *iface, isc_nmsocket_t *sock, uv_os_sock_t fd,
        if (isc__netmgr->load_balance_sockets) {
                csock->fd = isc__nm_udp_lb_socket(iface->type.sa.sa_family);
        } else {
+               INSIST(fd >= 0);
                csock->fd = dup(fd);
        }
        INSIST(csock->fd >= 0);