[PATCH net-next 3/4] netconsole: reject enabling a target with no remote IP address

The command-line path already requires a remote address, but if a user
creates a dynamic target and enables it without setting a remote
address, we currently try sending netconsole traffic to "0.0.0.0".

Refuse to enable a target if the remote address is unset.

Signed-off-by: Gustavo Luiz Duarte <[email protected]>
---
 drivers/net/netconsole.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 070bae7b4fd7..a41b0a5ce64f 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -471,6 +471,12 @@ static int netcons_netpoll_setup(struct netconsole_target *nt)
 	int err;
 
 	rtnl_lock();
+	if (nt->remote_ip.family == AF_UNSPEC) {
+		np_err(np, "remote IP address not configured, aborting\n");
+		err = -EDESTADDRREQ;
+		goto unlock;
+	}
+
 	if (np->dev_name[0])
 		ndev = __dev_get_by_name(net, np->dev_name);
 	else if (is_valid_ether_addr(np->dev_mac))

-- 
2.55.0