batman-adv: fix elp packet data reservation

commit 1e5d343b8f23770e8ac5d31f5c439826bdb35148 upstream.

The skb_reserve() call only reserved headroom for the mac header, but
not the elp packet header itself.

Fixing this by using skb_put()'ing towards the skb tail instead of
skb_push()'ing towards the skb head.

Fixes: d6f94d91f766 ("batman-adv: ELP - adding basic infrastructure")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index df42eb1365a0122ce08d1fe7657492745f4957a8..63762b3df7c78517cf21edf2603dfa39bed43e00 100644 (file)
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -334,7 +334,7 @@ int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface)
                goto out;
 
        skb_reserve(hard_iface->bat_v.elp_skb, ETH_HLEN + NET_IP_ALIGN);
-       elp_buff = skb_push(hard_iface->bat_v.elp_skb, BATADV_ELP_HLEN);
+       elp_buff = skb_put(hard_iface->bat_v.elp_skb, BATADV_ELP_HLEN);
        elp_packet = (struct batadv_elp_packet *)elp_buff;
        memset(elp_packet, 0, BATADV_ELP_HLEN);