[PATCH v7 1/3] batman-adv: netlink: reduce duplicate code by returning interfaces

["Linus Lüssing" <linus.luessing@c0d3.blue>]

Reduce duplicate code by using netlink helpers which return the
soft/hard interface directly. Instead of returning an interface index
which we are typically not interested in.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
 net/batman-adv/bridge_loop_avoidance.c |  30 +----
 net/batman-adv/distributed-arp-table.c |  15 +--
 net/batman-adv/gateway_client.c        |  15 +--
 net/batman-adv/multicast.c             |  14 +--
 net/batman-adv/netlink.c               | 146 +++++++++++++++++--------
 net/batman-adv/netlink.h               |   5 +-
 net/batman-adv/originator.c            |  80 ++++----------
 net/batman-adv/translation-table.c     |  28 +----
 8 files changed, 150 insertions(+), 183 deletions(-)

diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 449faf5a5487..bdedcbde9e0e 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -2233,25 +2233,16 @@ int batadv_bla_claim_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
 	struct batadv_hard_iface *primary_if = NULL;
 	int portid = NETLINK_CB(cb->skb).portid;
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_hashtable *hash;
 	struct batadv_priv *bat_priv;
 	int bucket = cb->args[0];
 	int idx = cb->args[1];
-	int ifindex;
 	int ret = 0;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh,
-					     BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 	hash = bat_priv->bla.claim_hash;
@@ -2403,25 +2394,16 @@ int batadv_bla_backbone_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
 	struct batadv_hard_iface *primary_if = NULL;
 	int portid = NETLINK_CB(cb->skb).portid;
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_hashtable *hash;
 	struct batadv_priv *bat_priv;
 	int bucket = cb->args[0];
 	int idx = cb->args[1];
-	int ifindex;
 	int ret = 0;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh,
-					     BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 	hash = bat_priv->bla.backbone_hash;
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index 801eff8a40e5..3a257fe07433 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -937,25 +937,16 @@ int batadv_dat_cache_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
 	struct batadv_hard_iface *primary_if = NULL;
 	int portid = NETLINK_CB(cb->skb).portid;
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_hashtable *hash;
 	struct batadv_priv *bat_priv;
 	int bucket = cb->args[0];
 	int idx = cb->args[1];
-	int ifindex;
 	int ret = 0;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh,
-					     BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 	hash = bat_priv->dat.hash;
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index 0ddd8b4b3f4c..8fa82742295d 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -502,22 +502,13 @@ void batadv_gw_node_free(struct batadv_priv *bat_priv)
 int batadv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
 	struct batadv_hard_iface *primary_if = NULL;
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_priv *bat_priv;
-	int ifindex;
 	int ret;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh,
-					     BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
index 38fab5e46ae2..1fc4f244d58a 100644
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -2112,21 +2112,13 @@ batadv_mcast_netlink_get_primary(struct netlink_callback *cb,
 				 struct batadv_hard_iface **primary_if)
 {
 	struct batadv_hard_iface *hard_iface = NULL;
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_priv *bat_priv;
-	int ifindex;
 	int ret = 0;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 3f0003fc502c..ce8e02d082d0 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -158,8 +158,7 @@ static const struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
  *
  * Return: interface index, or 0.
  */
-int
-batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype)
+static int batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype)
 {
 	struct nlattr *attr = nlmsg_find_attr(nlh, GENL_HDRLEN, attrtype);
 
@@ -881,14 +880,14 @@ static int batadv_netlink_notify_hardif(struct batadv_priv *bat_priv,
 }
 
 /**
- * batadv_netlink_get_hardif() - Get hardif attributes
+ * batadv_netlink_cmd_get_hardif() - Get hardif attributes
  * @skb: Netlink message with request data
  * @info: receiver information
  *
  * Return: 0 on success or negative error number in case of failure
  */
-static int batadv_netlink_get_hardif(struct sk_buff *skb,
-				     struct genl_info *info)
+static int batadv_netlink_cmd_get_hardif(struct sk_buff *skb,
+					 struct genl_info *info)
 {
 	struct batadv_hard_iface *hard_iface = info->user_ptr[1];
 	struct batadv_priv *bat_priv = info->user_ptr[0];
@@ -964,28 +963,16 @@ static int batadv_netlink_set_hardif(struct sk_buff *skb,
 static int
 batadv_netlink_dump_hardif(struct sk_buff *msg, struct netlink_callback *cb)
 {
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_hard_iface *hard_iface;
 	struct batadv_priv *bat_priv;
-	int ifindex;
 	int portid = NETLINK_CB(cb->skb).portid;
 	int skip = cb->args[0];
 	int i = 0;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh,
-					     BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface)
-		return -ENODEV;
-
-	if (!batadv_softif_is_valid(soft_iface)) {
-		dev_put(soft_iface);
-		return -ENODEV;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
@@ -1150,23 +1137,17 @@ static int batadv_netlink_set_vlan(struct sk_buff *skb, struct genl_info *info)
 }
 
 /**
- * batadv_get_softif_from_info() - Retrieve soft interface from genl attributes
+ * batadv_netlink_get_softif_from_info() - Retrieve soft interface from ifindex
  * @net: the applicable net namespace
- * @info: receiver information
+ * @ifindex: index of the soft interface
  *
  * Return: Pointer to soft interface (with increased refcnt) on success, error
  *  pointer on error
  */
 static struct net_device *
-batadv_get_softif_from_info(struct net *net, struct genl_info *info)
+batadv_netlink_get_softif_from_ifindex(struct net *net, int ifindex)
 {
 	struct net_device *soft_iface;
-	int ifindex;
-
-	if (!info->attrs[BATADV_ATTR_MESH_IFINDEX])
-		return ERR_PTR(-EINVAL);
-
-	ifindex = nla_get_u32(info->attrs[BATADV_ATTR_MESH_IFINDEX]);
 
 	soft_iface = dev_get_by_index(net, ifindex);
 	if (!soft_iface)
@@ -1184,28 +1165,61 @@ batadv_get_softif_from_info(struct net *net, struct genl_info *info)
 }
 
 /**
- * batadv_get_hardif_from_info() - Retrieve hardif from genl attributes
- * @bat_priv: the bat priv with all the soft interface information
+ * batadv_get_softif_from_info() - Retrieve soft interface from genl attributes
  * @net: the applicable net namespace
  * @info: receiver information
  *
+ * Return: Pointer to soft interface (with increased refcnt) on success, error
+ *  pointer on error
+ */
+static struct net_device *
+batadv_netlink_get_softif_from_info(struct net *net, struct genl_info *info)
+{
+	int ifindex;
+
+	if (!info->attrs[BATADV_ATTR_MESH_IFINDEX])
+		return ERR_PTR(-EINVAL);
+
+	ifindex = nla_get_u32(info->attrs[BATADV_ATTR_MESH_IFINDEX]);
+
+	return batadv_netlink_get_softif_from_ifindex(net, ifindex);
+}
+
+/**
+ * batadv_netlink_get_softif() - Retrieve soft interface from netlink callback
+ * @cb: callback structure containing arguments
+ *
+ * Return: Pointer to soft interface (with increased refcnt) on success, error
+ *  pointer on error
+ */
+struct net_device *batadv_netlink_get_softif(struct netlink_callback *cb)
+{
+	int ifindex = batadv_netlink_get_ifindex(cb->nlh,
+						 BATADV_ATTR_MESH_IFINDEX);
+	if (!ifindex)
+		return ERR_PTR(-ENONET);
+
+	return batadv_netlink_get_softif_from_ifindex(sock_net(cb->skb->sk),
+						      ifindex);
+}
+
+/**
+ * batadv_netlink_get_hardif_from_info() - Retrieve hard interface from ifindex
+ * @bat_priv: the bat priv with all the soft interface information
+ * @net: the applicable net namespace
+ * @ifindex: index of the hard interface
+ *
  * Return: Pointer to hard interface (with increased refcnt) on success, error
  *  pointer on error
  */
 static struct batadv_hard_iface *
-batadv_get_hardif_from_info(struct batadv_priv *bat_priv, struct net *net,
-			    struct genl_info *info)
+batadv_netlink_get_hardif_from_ifindex(struct batadv_priv *bat_priv,
+				       struct net *net, int ifindex)
 {
 	struct batadv_hard_iface *hard_iface;
 	struct net_device *hard_dev;
-	unsigned int hardif_index;
 
-	if (!info->attrs[BATADV_ATTR_HARD_IFINDEX])
-		return ERR_PTR(-EINVAL);
-
-	hardif_index = nla_get_u32(info->attrs[BATADV_ATTR_HARD_IFINDEX]);
-
-	hard_dev = dev_get_by_index(net, hardif_index);
+	hard_dev = dev_get_by_index(net, ifindex);
 	if (!hard_dev)
 		return ERR_PTR(-ENODEV);
 
@@ -1229,6 +1243,51 @@ batadv_get_hardif_from_info(struct batadv_priv *bat_priv, struct net *net,
 	return ERR_PTR(-EINVAL);
 }
 
+/**
+ * batadv_get_hardif_from_info() - Retrieve hardif from genl attributes
+ * @bat_priv: the bat priv with all the soft interface information
+ * @net: the applicable net namespace
+ * @info: receiver information
+ *
+ * Return: Pointer to hard interface (with increased refcnt) on success, error
+ *  pointer on error
+ */
+static struct batadv_hard_iface *
+batadv_netlink_get_hardif_from_info(struct batadv_priv *bat_priv,
+				    struct net *net, struct genl_info *info)
+{
+	int ifindex;
+
+	if (!info->attrs[BATADV_ATTR_HARD_IFINDEX])
+		return ERR_PTR(-EINVAL);
+
+	ifindex = nla_get_u32(info->attrs[BATADV_ATTR_HARD_IFINDEX]);
+
+	return batadv_netlink_get_hardif_from_ifindex(bat_priv, net, ifindex);
+}
+
+/**
+ * batadv_netlink_get_hardif() - Retrieve hard interface from netlink callback
+ * @bat_priv: the bat priv with all the soft interface information
+ * @cb: callback structure containing arguments
+ *
+ * Return: Pointer to hard interface (with increased refcnt) on success, error
+ *  pointer on error
+ */
+struct batadv_hard_iface *
+batadv_netlink_get_hardif(struct batadv_priv *bat_priv,
+			  struct netlink_callback *cb)
+{
+	int ifindex = batadv_netlink_get_ifindex(cb->nlh,
+						 BATADV_ATTR_HARD_IFINDEX);
+	if (!ifindex)
+		return ERR_PTR(-ENONET);
+
+	return batadv_netlink_get_hardif_from_ifindex(bat_priv,
+						      sock_net(cb->skb->sk),
+						      ifindex);
+}
+
 /**
  * batadv_get_vlan_from_info() - Retrieve vlan from genl attributes
  * @bat_priv: the bat priv with all the soft interface information
@@ -1288,7 +1347,7 @@ static int batadv_pre_doit(const struct genl_split_ops *ops,
 		return -EINVAL;
 
 	if (ops->internal_flags & BATADV_FLAG_NEED_MESH) {
-		soft_iface = batadv_get_softif_from_info(net, info);
+		soft_iface = batadv_netlink_get_softif_from_info(net, info);
 		if (IS_ERR(soft_iface))
 			return PTR_ERR(soft_iface);
 
@@ -1297,7 +1356,8 @@ static int batadv_pre_doit(const struct genl_split_ops *ops,
 	}
 
 	if (ops->internal_flags & BATADV_FLAG_NEED_HARDIF) {
-		hard_iface = batadv_get_hardif_from_info(bat_priv, net, info);
+		hard_iface = batadv_netlink_get_hardif_from_info(bat_priv, net,
+								 info);
 		if (IS_ERR(hard_iface)) {
 			ret = PTR_ERR(hard_iface);
 			goto err_put_softif;
@@ -1390,7 +1450,7 @@ static const struct genl_small_ops batadv_netlink_ops[] = {
 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 		/* can be retrieved by unprivileged users */
 		.dumpit = batadv_netlink_dump_hardif,
-		.doit = batadv_netlink_get_hardif,
+		.doit = batadv_netlink_cmd_get_hardif,
 		.internal_flags = BATADV_FLAG_NEED_MESH |
 				  BATADV_FLAG_NEED_HARDIF,
 	},
diff --git a/net/batman-adv/netlink.h b/net/batman-adv/netlink.h
index 876d2806a67d..2097c2ae98f1 100644
--- a/net/batman-adv/netlink.h
+++ b/net/batman-adv/netlink.h
@@ -15,7 +15,10 @@
 
 void batadv_netlink_register(void);
 void batadv_netlink_unregister(void);
-int batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype);
+struct net_device *batadv_netlink_get_softif(struct netlink_callback *cb);
+struct batadv_hard_iface *
+batadv_netlink_get_hardif(struct batadv_priv *bat_priv,
+			  struct netlink_callback *cb);
 
 int batadv_netlink_tpmeter_notify(struct batadv_priv *bat_priv, const u8 *dst,
 				  u8 result, u32 test_time, u64 total_bytes,
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 8f6dd2c6ee41..9ee9655d9bea 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -755,24 +755,15 @@ batadv_neigh_node_get_or_create(struct batadv_orig_node *orig_node,
  */
 int batadv_hardif_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
-	struct net_device *hard_iface = NULL;
-	struct batadv_hard_iface *hardif = BATADV_IF_DEFAULT;
+	struct batadv_hard_iface *hard_iface;
 	struct batadv_priv *bat_priv;
 	struct batadv_hard_iface *primary_if = NULL;
 	int ret;
-	int ifindex, hard_ifindex;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
@@ -782,22 +773,14 @@ int batadv_hardif_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb)
 		goto out;
 	}
 
-	hard_ifindex = batadv_netlink_get_ifindex(cb->nlh,
-						  BATADV_ATTR_HARD_IFINDEX);
-	if (hard_ifindex) {
-		hard_iface = dev_get_by_index(net, hard_ifindex);
-		if (hard_iface)
-			hardif = batadv_hardif_get_by_netdev(hard_iface);
-
-		if (!hardif) {
-			ret = -ENODEV;
+	hard_iface = batadv_netlink_get_hardif(bat_priv, cb);
+	if (IS_ERR(hard_iface)) {
+		if (PTR_ERR(hard_iface) != -ENONET) {
+			ret = PTR_ERR(hard_iface);
 			goto out;
 		}
 
-		if (hardif->soft_iface != soft_iface) {
-			ret = -ENOENT;
-			goto out;
-		}
+		hard_iface = BATADV_IF_DEFAULT;
 	}
 
 	if (!bat_priv->algo_ops->neigh.dump) {
@@ -805,13 +788,12 @@ int batadv_hardif_neigh_dump(struct sk_buff *msg, struct netlink_callback *cb)
 		goto out;
 	}
 
-	bat_priv->algo_ops->neigh.dump(msg, cb, bat_priv, hardif);
+	bat_priv->algo_ops->neigh.dump(msg, cb, bat_priv, hard_iface);
 
 	ret = msg->len;
 
  out:
-	batadv_hardif_put(hardif);
-	dev_put(hard_iface);
+	batadv_hardif_put(hard_iface);
 	batadv_hardif_put(primary_if);
 	dev_put(soft_iface);
 
@@ -1342,24 +1324,15 @@ static void batadv_purge_orig(struct work_struct *work)
  */
 int batadv_orig_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
-	struct net_device *hard_iface = NULL;
-	struct batadv_hard_iface *hardif = BATADV_IF_DEFAULT;
+	struct batadv_hard_iface *hard_iface = BATADV_IF_DEFAULT;
 	struct batadv_priv *bat_priv;
 	struct batadv_hard_iface *primary_if = NULL;
 	int ret;
-	int ifindex, hard_ifindex;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
@@ -1369,22 +1342,14 @@ int batadv_orig_dump(struct sk_buff *msg, struct netlink_callback *cb)
 		goto out;
 	}
 
-	hard_ifindex = batadv_netlink_get_ifindex(cb->nlh,
-						  BATADV_ATTR_HARD_IFINDEX);
-	if (hard_ifindex) {
-		hard_iface = dev_get_by_index(net, hard_ifindex);
-		if (hard_iface)
-			hardif = batadv_hardif_get_by_netdev(hard_iface);
-
-		if (!hardif) {
-			ret = -ENODEV;
+	hard_iface = batadv_netlink_get_hardif(bat_priv, cb);
+	if (IS_ERR(hard_iface)) {
+		if (PTR_ERR(hard_iface) != -ENONET) {
+			ret = PTR_ERR(hard_iface);
 			goto out;
 		}
 
-		if (hardif->soft_iface != soft_iface) {
-			ret = -ENOENT;
-			goto out;
-		}
+		hard_iface = BATADV_IF_DEFAULT;
 	}
 
 	if (!bat_priv->algo_ops->orig.dump) {
@@ -1392,13 +1357,12 @@ int batadv_orig_dump(struct sk_buff *msg, struct netlink_callback *cb)
 		goto out;
 	}
 
-	bat_priv->algo_ops->orig.dump(msg, cb, bat_priv, hardif);
+	bat_priv->algo_ops->orig.dump(msg, cb, bat_priv, hard_iface);
 
 	ret = msg->len;
 
  out:
-	batadv_hardif_put(hardif);
-	dev_put(hard_iface);
+	batadv_hardif_put(hard_iface);
 	batadv_hardif_put(primary_if);
 	dev_put(soft_iface);
 
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index bc122c4de73d..a94734a9c3b1 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -1161,26 +1161,18 @@ batadv_tt_local_dump_bucket(struct sk_buff *msg, u32 portid,
  */
 int batadv_tt_local_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_priv *bat_priv;
 	struct batadv_hard_iface *primary_if = NULL;
 	struct batadv_hashtable *hash;
 	int ret;
-	int ifindex;
 	int bucket = cb->args[0];
 	int idx = cb->args[1];
 	int portid = NETLINK_CB(cb->skb).portid;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
@@ -1936,28 +1928,20 @@ batadv_tt_global_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
  */
 int batadv_tt_global_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_priv *bat_priv;
 	struct batadv_hard_iface *primary_if = NULL;
 	struct batadv_hashtable *hash;
 	struct hlist_head *head;
 	int ret;
-	int ifindex;
 	int bucket = cb->args[0];
 	int idx = cb->args[1];
 	int sub = cb->args[2];
 	int portid = NETLINK_CB(cb->skb).portid;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
-- 
2.45.2