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Diffstat (limited to 'net/batman-adv/fragmentation.c')
-rw-r--r--net/batman-adv/fragmentation.c82
1 files changed, 49 insertions, 33 deletions
diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c
index 0934730fb7ff..9c561e683f4b 100644
--- a/net/batman-adv/fragmentation.c
+++ b/net/batman-adv/fragmentation.c
@@ -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>
@@ -42,17 +43,23 @@
/**
* batadv_frag_clear_chain - delete entries in the fragment buffer chain
* @head: head of chain with entries.
+ * @dropped: whether the chain is cleared because all fragments are dropped
*
* Free fragments in the passed hlist. Should be called with appropriate lock.
*/
-static void batadv_frag_clear_chain(struct hlist_head *head)
+static void batadv_frag_clear_chain(struct hlist_head *head, bool dropped)
{
struct batadv_frag_list_entry *entry;
struct hlist_node *node;
hlist_for_each_entry_safe(entry, node, head, list) {
hlist_del(&entry->list);
- kfree_skb(entry->skb);
+
+ if (dropped)
+ kfree_skb(entry->skb);
+ else
+ consume_skb(entry->skb);
+
kfree(entry);
}
}
@@ -73,7 +80,7 @@ void batadv_frag_purge_orig(struct batadv_orig_node *orig_node,
spin_lock_bh(&chain->lock);
if (!check_cb || check_cb(chain)) {
- batadv_frag_clear_chain(&chain->head);
+ batadv_frag_clear_chain(&chain->fragment_list, true);
chain->size = 0;
}
@@ -117,8 +124,8 @@ static bool batadv_frag_init_chain(struct batadv_frag_table_entry *chain,
if (chain->seqno == seqno)
return false;
- if (!hlist_empty(&chain->head))
- batadv_frag_clear_chain(&chain->head);
+ if (!hlist_empty(&chain->fragment_list))
+ batadv_frag_clear_chain(&chain->fragment_list, true);
chain->size = 0;
chain->seqno = seqno;
@@ -176,7 +183,7 @@ static bool batadv_frag_insert_packet(struct batadv_orig_node *orig_node,
chain = &orig_node->fragments[bucket];
spin_lock_bh(&chain->lock);
if (batadv_frag_init_chain(chain, seqno)) {
- hlist_add_head(&frag_entry_new->list, &chain->head);
+ hlist_add_head(&frag_entry_new->list, &chain->fragment_list);
chain->size = skb->len - hdr_size;
chain->timestamp = jiffies;
chain->total_size = ntohs(frag_packet->total_size);
@@ -185,7 +192,7 @@ static bool batadv_frag_insert_packet(struct batadv_orig_node *orig_node,
}
/* Find the position for the new fragment. */
- hlist_for_each_entry(frag_entry_curr, &chain->head, list) {
+ hlist_for_each_entry(frag_entry_curr, &chain->fragment_list, list) {
/* Drop packet if fragment already exists. */
if (frag_entry_curr->no == frag_entry_new->no)
goto err_unlock;
@@ -220,11 +227,11 @@ out:
* exceeds the maximum size of one merged packet. Don't allow
* packets to have different total_size.
*/
- batadv_frag_clear_chain(&chain->head);
+ batadv_frag_clear_chain(&chain->fragment_list, true);
chain->size = 0;
} else if (ntohs(frag_packet->total_size) == chain->size) {
/* All fragments received. Hand over chain to caller. */
- hlist_move_list(&chain->head, chain_out);
+ hlist_move_list(&chain->fragment_list, chain_out);
chain->size = 0;
}
@@ -252,8 +259,9 @@ batadv_frag_merge_packets(struct hlist_head *chain)
{
struct batadv_frag_packet *packet;
struct batadv_frag_list_entry *entry;
- struct sk_buff *skb_out = NULL;
+ struct sk_buff *skb_out;
int size, hdr_size = sizeof(struct batadv_frag_packet);
+ bool dropped = false;
/* Remove first entry, as this is the destination for the rest of the
* fragments.
@@ -270,6 +278,7 @@ batadv_frag_merge_packets(struct hlist_head *chain)
if (pskb_expand_head(skb_out, 0, size - skb_out->len, GFP_ATOMIC) < 0) {
kfree_skb(skb_out);
skb_out = NULL;
+ dropped = true;
goto free;
}
@@ -291,7 +300,7 @@ batadv_frag_merge_packets(struct hlist_head *chain)
free:
/* Locking is not needed, because 'chain' is not part of any orig. */
- batadv_frag_clear_chain(chain);
+ batadv_frag_clear_chain(chain, dropped);
return skb_out;
}
@@ -352,7 +361,7 @@ bool batadv_frag_skb_fwd(struct sk_buff *skb,
struct batadv_orig_node *orig_node_src)
{
struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
- struct batadv_orig_node *orig_node_dst = NULL;
+ struct batadv_orig_node *orig_node_dst;
struct batadv_neigh_node *neigh_node = NULL;
struct batadv_frag_packet *packet;
u16 total_size;
@@ -433,8 +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,
@@ -447,7 +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
@@ -457,13 +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;
@@ -488,34 +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);
@@ -524,10 +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;
}