[3/6] batman-adv: Consume skb in batadv_frag_send_packet
Commit Message
Sending functions in Linux consume the supplied skbuff. Doing the same in
batadv_frag_send_packet avoids the hack of returning -1 (-EPERM) to signal
the caller that he is responsible for cleaning up the skb.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
---
net/batman-adv/fragmentation.c | 50 ++++++++++++++++++++++++------------------
1 file changed, 29 insertions(+), 21 deletions(-)
@@ -20,6 +20,7 @@
#include <linux/atomic.h>
#include <linux/byteorder/generic.h>
+#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
@@ -441,8 +442,7 @@ err:
* @orig_node: final destination of the created fragments
* @neigh_node: next-hop of the created fragments
*
- * Return: the netdev tx status or -1 in case of error.
- * When -1 is returned the skb is not consumed.
+ * Return: the netdev tx status or a negative errno code on a failure
*/
int batadv_frag_send_packet(struct sk_buff *skb,
struct batadv_orig_node *orig_node,
@@ -455,7 +455,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
unsigned int mtu = neigh_node->if_incoming->net_dev->mtu;
unsigned int header_size = sizeof(frag_header);
unsigned int max_fragment_size, max_packet_size;
- int ret = -1;
+ int ret;
/* To avoid merge and refragmentation at next-hops we never send
* fragments larger than BATADV_FRAG_MAX_FRAG_SIZE
@@ -465,13 +465,17 @@ int batadv_frag_send_packet(struct sk_buff *skb,
max_packet_size = max_fragment_size * BATADV_FRAG_MAX_FRAGMENTS;
/* Don't even try to fragment, if we need more than 16 fragments */
- if (skb->len > max_packet_size)
- goto out;
+ if (skb->len > max_packet_size) {
+ ret = -EAGAIN;
+ goto free_skb;
+ }
bat_priv = orig_node->bat_priv;
primary_if = batadv_primary_if_get_selected(bat_priv);
- if (!primary_if)
- goto out;
+ if (!primary_if) {
+ ret = -EINVAL;
+ goto put_primary_if;
+ }
/* Create one header to be copied to all fragments */
frag_header.packet_type = BATADV_UNICAST_FRAG;
@@ -496,34 +500,35 @@ int batadv_frag_send_packet(struct sk_buff *skb,
/* Eat and send fragments from the tail of skb */
while (skb->len > max_fragment_size) {
skb_fragment = batadv_frag_create(skb, &frag_header, mtu);
- if (!skb_fragment)
- goto out;
+ if (!skb_fragment) {
+ ret = -ENOMEM;
+ goto free_skb;
+ }
batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_TX);
batadv_add_counter(bat_priv, BATADV_CNT_FRAG_TX_BYTES,
skb_fragment->len + ETH_HLEN);
ret = batadv_send_unicast_skb(skb_fragment, neigh_node);
if (ret != NET_XMIT_SUCCESS) {
- /* return -1 so that the caller can free the original
- * skb
- */
- ret = -1;
- goto out;
+ ret = NET_XMIT_DROP;
+ goto free_skb;
}
frag_header.no++;
/* The initial check in this function should cover this case */
if (frag_header.no == BATADV_FRAG_MAX_FRAGMENTS - 1) {
- ret = -1;
- goto out;
+ ret = -EINVAL;
+ goto free_skb;
}
}
/* Make room for the fragment header. */
if (batadv_skb_head_push(skb, header_size) < 0 ||
- pskb_expand_head(skb, header_size + ETH_HLEN, 0, GFP_ATOMIC) < 0)
- goto out;
+ pskb_expand_head(skb, header_size + ETH_HLEN, 0, GFP_ATOMIC) < 0) {
+ ret = -ENOMEM;
+ goto free_skb;
+ }
memcpy(skb->data, &frag_header, header_size);
@@ -532,10 +537,13 @@ int batadv_frag_send_packet(struct sk_buff *skb,
batadv_add_counter(bat_priv, BATADV_CNT_FRAG_TX_BYTES,
skb->len + ETH_HLEN);
ret = batadv_send_unicast_skb(skb, neigh_node);
+ /* skb was consumed */
+ skb = NULL;
-out:
- if (primary_if)
- batadv_hardif_put(primary_if);
+put_primary_if:
+ batadv_hardif_put(primary_if);
+free_skb:
+ kfree_skb(skb);
return ret;
}