[PATCH net-next v2 5/6] netconsole: show empty string for an unset IP address

[Gustavo Luiz Duarte]

An unset address (local_ip/remote_ip), now denoted by AF_UNSPEC,
currently shows "0.0.0.0" in configfs. Print an empty string instead,
which is more clear.

In netconsole_print_banner() we can be even more explicit about it, as
we don't have the risk of userspace trying to parse it.

Signed-off-by: Gustavo Luiz Duarte <gustavold@xxxxxxxxx>
---
 drivers/net/netconsole.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 054c39066043..0418031b6bc9 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -705,14 +705,18 @@ static void netconsole_print_banner(struct netconsole_target *nt)
 	struct netpoll *np = &nt->np;
 
 	np_info(np, "local port %d\n", nt->local_port);
-	if (nt->local_ip.family == AF_INET6)
+	if (nt->local_ip.family == AF_UNSPEC)
+		np_info(np, "local IP unset\n");
+	else if (nt->local_ip.family == AF_INET6)
 		np_info(np, "local IPv6 address %pI6c\n", &nt->local_ip.in6);
 	else
 		np_info(np, "local IPv4 address %pI4\n", &nt->local_ip.ip);
 	np_info(np, "interface name '%s'\n", np->dev_name);
 	np_info(np, "local ethernet address '%pM'\n", np->dev_mac);
 	np_info(np, "remote port %d\n", nt->remote_port);
-	if (nt->remote_ip.family == AF_INET6)
+	if (nt->remote_ip.family == AF_UNSPEC)
+		np_info(np, "remote IP unset\n");
+	else if (nt->remote_ip.family == AF_INET6)
 		np_info(np, "remote IPv6 address %pI6c\n", &nt->remote_ip.in6);
 	else
 		np_info(np, "remote IPv4 address %pI4\n", &nt->remote_ip.ip);
@@ -850,6 +854,8 @@ static ssize_t local_ip_show(struct config_item *item, char *buf)
 {
 	struct netconsole_target *nt = to_target(item);
 
+	if (nt->local_ip.family == AF_UNSPEC)
+		return sysfs_emit(buf, "\n");
 	if (nt->local_ip.family == AF_INET6)
 		return sysfs_emit(buf, "%pI6c\n", &nt->local_ip.in6);
 	else
@@ -860,6 +866,8 @@ static ssize_t remote_ip_show(struct config_item *item, char *buf)
 {
 	struct netconsole_target *nt = to_target(item);
 
+	if (nt->remote_ip.family == AF_UNSPEC)
+		return sysfs_emit(buf, "\n");
 	if (nt->remote_ip.family == AF_INET6)
 		return sysfs_emit(buf, "%pI6c\n", &nt->remote_ip.in6);
 	else

-- 
2.55.0