From 9fbfca013176f9b90d186f3b446fd93e4d972b25 Mon Sep 17 00:00:00 2001
From: Allan Stephens <allan.stephens@windriver.com>
Date: Fri, 3 Sep 2010 08:33:40 +0000
Subject: [PATCH] tipc: Ensure outgoing messages on Ethernet have sufficient
headroom
Add code to expand the headroom of an outgoing TIPC message if the
sk_buff has insufficient room to hold the header for the associated
Ethernet device. This change is necessary to ensure that messages
TIPC does not create itself (eg. incoming messages that are being
routed to another node) do not cause problems, since TIPC has no
control over the amount of headroom available in such messages.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/tipc/eth_media.c | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)
diff --git a/net/tipc/eth_media.c b/net/tipc/eth_media.c
index 6230d16020c4..81253d0b24b9 100644
--- a/net/tipc/eth_media.c
+++ b/net/tipc/eth_media.c
@@ -72,17 +72,26 @@ static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
{
struct sk_buff *clone;
struct net_device *dev;
+ int delta;
clone = skb_clone(buf, GFP_ATOMIC);
- if (clone) {
- skb_reset_network_header(clone);
- dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev;
- clone->dev = dev;
- dev_hard_header(clone, dev, ETH_P_TIPC,
- &dest->dev_addr.eth_addr,
- dev->dev_addr, clone->len);
- dev_queue_xmit(clone);
+ if (!clone)
+ return 0;
+
+ dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev;
+ delta = dev->hard_header_len - skb_headroom(buf);
+
+ if ((delta > 0) &&
+ pskb_expand_head(clone, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) {
+ kfree_skb(clone);
+ return 0;
}
+
+ skb_reset_network_header(clone);
+ clone->dev = dev;
+ dev_hard_header(clone, dev, ETH_P_TIPC, &dest->dev_addr.eth_addr,
+ dev->dev_addr, clone->len);
+ dev_queue_xmit(clone);
return 0;
}