From: Sven Eckelmann <sven@narfation.org>
Date: Tue, 27 Dec 2016 08:51:17 +0100
Subject: batman-adv: Decrease hardif refcnt on fragmentation send error

An error before the hardif is found has to free the skb. But every error
after that has to free the skb + put the hard interface.

Fixes: 8b4132b1447a ("batman-adv: Consume skb in batadv_frag_send_packet")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

Origin: upstream, https://git.open-mesh.org/batman-adv.git/commit/205dc8385dc863467f4f6ccec2e63254e6baf831

diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c
index 9c561e683f4b8b68642b626b51a0dcda30260e97..0854ebd8613e9bf9044b04099b11341325d6e194 100644
--- a/net/batman-adv/fragmentation.c
+++ b/net/batman-adv/fragmentation.c
@@ -474,7 +474,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
 	primary_if = batadv_primary_if_get_selected(bat_priv);
 	if (!primary_if) {
 		ret = -EINVAL;
-		goto put_primary_if;
+		goto free_skb;
 	}
 
 	/* Create one header to be copied to all fragments */
@@ -502,7 +502,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
 		skb_fragment = batadv_frag_create(skb, &frag_header, mtu);
 		if (!skb_fragment) {
 			ret = -ENOMEM;
-			goto free_skb;
+			goto put_primary_if;
 		}
 
 		batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_TX);
@@ -511,7 +511,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
 		ret = batadv_send_unicast_skb(skb_fragment, neigh_node);
 		if (ret != NET_XMIT_SUCCESS) {
 			ret = NET_XMIT_DROP;
-			goto free_skb;
+			goto put_primary_if;
 		}
 
 		frag_header.no++;
@@ -519,7 +519,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
 		/* The initial check in this function should cover this case */
 		if (frag_header.no == BATADV_FRAG_MAX_FRAGMENTS - 1) {
 			ret = -EINVAL;
-			goto free_skb;
+			goto put_primary_if;
 		}
 	}
 
@@ -527,7 +527,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
 	if (batadv_skb_head_push(skb, header_size) < 0 ||
 	    pskb_expand_head(skb, header_size + ETH_HLEN, 0, GFP_ATOMIC) < 0) {
 		ret = -ENOMEM;
-		goto free_skb;
+		goto put_primary_if;
 	}
 
 	memcpy(skb->data, &frag_header, header_size);