[v3] batman-adv: Directly prepare icmp packets in socket buffer
Commit Message
It is unnecessary to generate an icmp packet in an extra memory region
and than copying it to a new allocated skb.
This also resolved the problem that we do inform the user that we
couldn't send the packet because we couldn't allocate the socket buffer.
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
---
Return -ENOMEM when dev_alloc_skb fails.
batman-adv/icmp_socket.c | 60 +++++++++++++++++++++++++++++-----------------
1 files changed, 38 insertions(+), 22 deletions(-)
Comments
On Friday 23 July 2010 22:49:24 Sven Eckelmann wrote:
> It is unnecessary to generate an icmp packet in an extra memory region
> and than copying it to a new allocated skb.
>
> This also resolved the problem that we do inform the user that we
> couldn't send the packet because we couldn't allocate the socket buffer.
>
> Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Applied in revision 1745.
Thanks,
Marek
@@ -156,7 +156,8 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
/* FIXME: each orig_node->batman_if will be attached to a softif */
struct bat_priv *bat_priv = netdev_priv(soft_device);
struct socket_client *socket_client = file->private_data;
- struct icmp_packet_rr icmp_packet;
+ struct sk_buff *skb;
+ struct icmp_packet_rr *icmp_packet;
struct orig_node *orig_node;
struct batman_if *batman_if;
size_t packet_len = sizeof(struct icmp_packet);
@@ -173,40 +174,53 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
if (len >= sizeof(struct icmp_packet_rr))
packet_len = sizeof(struct icmp_packet_rr);
- if (!access_ok(VERIFY_READ, buff, packet_len))
- return -EFAULT;
+ skb = dev_alloc_skb(packet_len + sizeof(struct ethhdr));
+ if (!skb)
+ return -ENOMEM;
- if (__copy_from_user(&icmp_packet, buff, packet_len))
- return -EFAULT;
+ skb_reserve(skb, sizeof(struct ethhdr));
+ icmp_packet = (struct icmp_packet_rr *)skb_put(skb, packet_len);
- if (icmp_packet.packet_type != BAT_ICMP) {
+ if (!access_ok(VERIFY_READ, buff, packet_len)) {
+ len = -EFAULT;
+ goto free_skb;
+ }
+
+ if (__copy_from_user(icmp_packet, buff, packet_len)) {
+ len = -EFAULT;
+ goto free_skb;
+ }
+
+ if (icmp_packet->packet_type != BAT_ICMP) {
bat_dbg(DBG_BATMAN, bat_priv,
"Error - can't send packet from char device: "
"got bogus packet type (expected: BAT_ICMP)\n");
- return -EINVAL;
+ len = -EINVAL;
+ goto free_skb;
}
- if (icmp_packet.msg_type != ECHO_REQUEST) {
+ if (icmp_packet->msg_type != ECHO_REQUEST) {
bat_dbg(DBG_BATMAN, bat_priv,
"Error - can't send packet from char device: "
"got bogus message type (expected: ECHO_REQUEST)\n");
- return -EINVAL;
+ len = -EINVAL;
+ goto free_skb;
}
- icmp_packet.uid = socket_client->index;
+ icmp_packet->uid = socket_client->index;
- if (icmp_packet.version != COMPAT_VERSION) {
- icmp_packet.msg_type = PARAMETER_PROBLEM;
- icmp_packet.ttl = COMPAT_VERSION;
- bat_socket_add_packet(socket_client, &icmp_packet, packet_len);
- goto out;
+ if (icmp_packet->version != COMPAT_VERSION) {
+ icmp_packet->msg_type = PARAMETER_PROBLEM;
+ icmp_packet->ttl = COMPAT_VERSION;
+ bat_socket_add_packet(socket_client, icmp_packet, packet_len);
+ goto free_skb;
}
if (atomic_read(&module_state) != MODULE_ACTIVE)
goto dst_unreach;
spin_lock_irqsave(&orig_hash_lock, flags);
- orig_node = ((struct orig_node *)hash_find(orig_hash, icmp_packet.dst));
+ orig_node = (struct orig_node *)hash_find(orig_hash, icmp_packet->dst);
if (!orig_node)
goto unlock;
@@ -225,21 +239,23 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
if (batman_if->if_status != IF_ACTIVE)
goto dst_unreach;
- memcpy(icmp_packet.orig, batman_if->net_dev->dev_addr, ETH_ALEN);
+ memcpy(icmp_packet->orig, batman_if->net_dev->dev_addr, ETH_ALEN);
if (packet_len == sizeof(struct icmp_packet_rr))
- memcpy(icmp_packet.rr, batman_if->net_dev->dev_addr, ETH_ALEN);
+ memcpy(icmp_packet->rr, batman_if->net_dev->dev_addr, ETH_ALEN);
- send_raw_packet((unsigned char *)&icmp_packet,
- packet_len, batman_if, dstaddr);
+
+ send_skb_packet(skb, batman_if, dstaddr);
goto out;
unlock:
spin_unlock_irqrestore(&orig_hash_lock, flags);
dst_unreach:
- icmp_packet.msg_type = DESTINATION_UNREACHABLE;
- bat_socket_add_packet(socket_client, &icmp_packet, packet_len);
+ icmp_packet->msg_type = DESTINATION_UNREACHABLE;
+ bat_socket_add_packet(socket_client, icmp_packet, packet_len);
+free_skb:
+ kfree_skb(skb);
out:
return len;
}