net: devlink: don't ignore errors during dumpit

Currently, some dumpit function may end-up with error which is not
-EMSGSIZE and this error is silently ignored. Use does not have clue
that something wrong happened. Instead of silent ignore, propagate
the error to user.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/devlink.c

@@ -1044,7 +1044,7 @@ static int devlink_nl_cmd_sb_pool_get_dumpit(struct sk_buff *msg,
 	struct devlink_sb *devlink_sb;
 	int start = cb->args[0];
 	int idx = 0;
-	int err;
+	int err = 0;
 
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
@@ -1067,6 +1067,9 @@ static int devlink_nl_cmd_sb_pool_get_dumpit(struct sk_buff *msg,
 out:
 	mutex_unlock(&devlink_mutex);
 
+	if (err != -EMSGSIZE)
+		return err;
+
 	cb->args[0] = idx;
 	return msg->len;
 }
@@ -1242,7 +1245,7 @@ static int devlink_nl_cmd_sb_port_pool_get_dumpit(struct sk_buff *msg,
 	struct devlink_sb *devlink_sb;
 	int start = cb->args[0];
 	int idx = 0;
-	int err;
+	int err = 0;
 
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
@@ -1265,6 +1268,9 @@ static int devlink_nl_cmd_sb_port_pool_get_dumpit(struct sk_buff *msg,
 out:
 	mutex_unlock(&devlink_mutex);
 
+	if (err != -EMSGSIZE)
+		return err;
+
 	cb->args[0] = idx;
 	return msg->len;
 }
@@ -1469,7 +1475,7 @@ devlink_nl_cmd_sb_tc_pool_bind_get_dumpit(struct sk_buff *msg,
 	struct devlink_sb *devlink_sb;
 	int start = cb->args[0];
 	int idx = 0;
-	int err;
+	int err = 0;
 
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
@@ -1494,6 +1500,9 @@ devlink_nl_cmd_sb_tc_pool_bind_get_dumpit(struct sk_buff *msg,
 out:
 	mutex_unlock(&devlink_mutex);
 
+	if (err != -EMSGSIZE)
+		return err;
+
 	cb->args[0] = idx;
 	return msg->len;
 }
@@ -3257,7 +3266,7 @@ static int devlink_nl_cmd_param_get_dumpit(struct sk_buff *msg,
 	struct devlink *devlink;
 	int start = cb->args[0];
 	int idx = 0;
-	int err;
+	int err = 0;
 
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
@@ -3285,6 +3294,9 @@ static int devlink_nl_cmd_param_get_dumpit(struct sk_buff *msg,
 out:
 	mutex_unlock(&devlink_mutex);
 
+	if (err != -EMSGSIZE)
+		return err;
+
 	cb->args[0] = idx;
 	return msg->len;
 }
@@ -3513,7 +3525,7 @@ static int devlink_nl_cmd_port_param_get_dumpit(struct sk_buff *msg,
 	struct devlink *devlink;
 	int start = cb->args[0];
 	int idx = 0;
-	int err;
+	int err = 0;
 
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
@@ -3546,6 +3558,9 @@ static int devlink_nl_cmd_port_param_get_dumpit(struct sk_buff *msg,
 out:
 	mutex_unlock(&devlink_mutex);
 
+	if (err != -EMSGSIZE)
+		return err;
+
 	cb->args[0] = idx;
 	return msg->len;
 }
@@ -4168,7 +4183,7 @@ static int devlink_nl_cmd_info_get_dumpit(struct sk_buff *msg,
 	struct devlink *devlink;
 	int start = cb->args[0];
 	int idx = 0;
-	int err;
+	int err = 0;
 
 	mutex_lock(&devlink_mutex);
 	list_for_each_entry(devlink, &devlink_list, list) {
@@ -4196,6 +4211,9 @@ static int devlink_nl_cmd_info_get_dumpit(struct sk_buff *msg,
 	}
 	mutex_unlock(&devlink_mutex);
 
+	if (err != -EMSGSIZE)
+		return err;
+
 	cb->args[0] = idx;
 	return msg->len;
 }