diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index ead02c9e0848..c40c9e02391b 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -1066,6 +1066,9 @@ static u16 batadv_arp_get_type(struct batadv_priv *bat_priv, * @skb: the buffer containing the packet to extract the VID from * @hdr_size: the size of the batman-adv header encapsulating the packet * + * The caller must ensure that at least @hdr_size + ETH_HLEN bytes are + * accessible after skb->data. + * * Return: If the packet embedded in the skb is vlan tagged this function * returns the VID with the BATADV_VLAN_HAS_TAG flag. Otherwise BATADV_NO_FLAGS * is returned. @@ -1148,6 +1151,10 @@ bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv, if (!READ_ONCE(bat_priv->distributed_arp_table)) goto out; + /* first, find out the vid. */ + if (!pskb_may_pull(skb, hdr_size + ETH_HLEN)) + goto out; + vid = batadv_dat_get_vid(skb, &hdr_size); type = batadv_arp_get_type(bat_priv, skb, hdr_size); @@ -1243,6 +1250,10 @@ bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv, if (!READ_ONCE(bat_priv->distributed_arp_table)) goto out; + /* first, find out the vid. */ + if (!pskb_may_pull(skb, hdr_size + ETH_HLEN)) + goto out; + vid = batadv_dat_get_vid(skb, &hdr_size); type = batadv_arp_get_type(bat_priv, skb, hdr_size); @@ -1305,6 +1316,10 @@ void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv, if (!READ_ONCE(bat_priv->distributed_arp_table)) return; + /* first, find out the vid. */ + if (!pskb_may_pull(skb, hdr_size + ETH_HLEN)) + return; + vid = batadv_dat_get_vid(skb, &hdr_size); type = batadv_arp_get_type(bat_priv, skb, hdr_size); @@ -1353,6 +1368,10 @@ bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, if (!READ_ONCE(bat_priv->distributed_arp_table)) goto out; + /* first, find out the vid. */ + if (!pskb_may_pull(skb, hdr_size + ETH_HLEN)) + goto out; + vid = batadv_dat_get_vid(skb, &hdr_size); type = batadv_arp_get_type(bat_priv, skb, hdr_size); @@ -1807,6 +1826,10 @@ bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv, if (batadv_forw_packet_is_rebroadcast(forw_packet)) goto out; + /* first, find out the vid. */ + if (!pskb_may_pull(forw_packet->skb, hdr_size + ETH_HLEN)) + goto out; + vid = batadv_dat_get_vid(forw_packet->skb, &hdr_size); type = batadv_arp_get_type(bat_priv, forw_packet->skb, hdr_size); diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c index 3c4572284b53..4d3807a645b7 100644 --- a/net/batman-adv/main.c +++ b/net/batman-adv/main.c @@ -580,6 +580,9 @@ void batadv_recv_handler_unregister(u8 packet_type) * @skb: the buffer containing the packet * @header_len: length of the batman header preceding the ethernet header * + * The caller must ensure that at least @header_len + ETH_HLEN bytes are + * accessible after skb->data. + * * Return: VID with the BATADV_VLAN_HAS_TAG flag when the packet embedded in the * skb is vlan tagged. Otherwise BATADV_NO_FLAGS. */