Staging: batman-adv: Provide full headers and packets as linear skb

We must ensure that all interesting data is linear and not paged out to
access all information in a header or a full batman-adv related packet.
Otherwise we may drop packets which have non-linear headers but which
hold valid data.

This doesn't affect non-linear skbs which have all headers in a linear
head unless we must process the whole packet like in ogms or vis
packets.

Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Sven Eckelmann 2010-09-05 01:58:33 +02:00 committed by Greg Kroah-Hartman
parent aedbffc777
commit bf3264f6d1
2 changed files with 15 additions and 9 deletions

View File

@ -486,7 +486,7 @@ int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
goto err_free;
/* packet should hold at least type and version */
if (unlikely(skb_headlen(skb) < 2))
if (unlikely(!pskb_may_pull(skb, 2)))
goto err_free;
/* expect a valid ethernet header here. */

View File

@ -744,7 +744,7 @@ int recv_bat_packet(struct sk_buff *skb,
unsigned long flags;
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < sizeof(struct batman_packet))
if (unlikely(!pskb_may_pull(skb, sizeof(struct batman_packet))))
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
@ -761,6 +761,10 @@ int recv_bat_packet(struct sk_buff *skb,
if (skb_cow(skb, 0) < 0)
return NET_RX_DROP;
/* keep skb linear */
if (skb_linearize(skb) < 0)
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
spin_lock_irqsave(&orig_hash_lock, flags);
@ -914,11 +918,11 @@ int recv_icmp_packet(struct sk_buff *skb)
/**
* we truncate all incoming icmp packets if they don't match our size
*/
if (skb_headlen(skb) >= sizeof(struct icmp_packet_rr))
if (skb->len >= sizeof(struct icmp_packet_rr))
hdr_size = sizeof(struct icmp_packet_rr);
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < hdr_size)
if (unlikely(!pskb_may_pull(skb, hdr_size)))
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
@ -1087,7 +1091,7 @@ static int check_unicast_packet(struct sk_buff *skb, int hdr_size)
struct ethhdr *ethhdr;
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < hdr_size)
if (unlikely(!pskb_may_pull(skb, hdr_size)))
return -1;
ethhdr = (struct ethhdr *) skb_mac_header(skb);
@ -1247,7 +1251,7 @@ int recv_bcast_packet(struct sk_buff *skb)
unsigned long flags;
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < hdr_size)
if (unlikely(!pskb_may_pull(skb, hdr_size)))
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
@ -1320,7 +1324,11 @@ int recv_vis_packet(struct sk_buff *skb)
struct bat_priv *bat_priv;
int hdr_size = sizeof(struct vis_packet);
if (skb_headlen(skb) < hdr_size)
/* keep skb linear */
if (skb_linearize(skb) < 0)
return NET_RX_DROP;
if (unlikely(!pskb_may_pull(skb, hdr_size)))
return NET_RX_DROP;
vis_packet = (struct vis_packet *) skb->data;
@ -1342,13 +1350,11 @@ int recv_vis_packet(struct sk_buff *skb)
switch (vis_packet->vis_type) {
case VIS_TYPE_SERVER_SYNC:
/* TODO: handle fragmented skbs properly */
receive_server_sync_packet(bat_priv, vis_packet,
skb_headlen(skb));
break;
case VIS_TYPE_CLIENT_UPDATE:
/* TODO: handle fragmented skbs properly */
receive_client_update_packet(bat_priv, vis_packet,
skb_headlen(skb));
break;