The maximum of hard_header_len and needed_headroom of all slave interfaces
of a batman-adv device must be used to define the batman-adv device
headroom/header_len. This is required to avoid too small headroom problems
when these slave devices try to send the encapsulated packet.
The batman-adv therefore uses:
needed_headroom = max(0, dev[0].needed_headroom, ...,
dev[n].needed_headroom)
hard_header_len = max(ETH_HLEN, dev[0].hard_header_len, ...,
dev[n].hard_header_len) + ETH_HLEN +
max(sizeof(batadv_*cast_packet))
Signed-off-by: Sven Eckelmann <[email protected]>
---
v2:
- based on patch "batman-adv: don't access unregistered net_device object"
- remove the function call from batadv_update_min_mtu
- instead use batadv_hardif_disable_interface + batadv_hardif_enable_interface
net/batman-adv/hard-interface.c | 36 ++++++++++++++++++++++++++++++++++--
net/batman-adv/soft-interface.c | 2 +-
2 files changed, 35 insertions(+), 3 deletions(-)
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index 0565b20bfa6d..4d253ebcd4bb 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -252,6 +252,33 @@ static void batadv_check_known_mac_addr(const struct
net_device *net_dev)
rcu_read_unlock();
}
+/**
+ * batadv_hardif_recalc_headroom() - Recalculate skbuff headroom parameters
+ * @soft_iface: netdev struct of the mesh interface
+ */
+static void batadv_hardif_recalc_headroom(struct net_device *soft_iface)
+{
+ const struct batadv_hard_iface *hard_iface;
+ unsigned short hard_header_len = ETH_HLEN;
+ unsigned short needed_headroom = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+ if (hard_iface->soft_iface != soft_iface)
+ continue;
+
+ hard_header_len = max_t(unsigned short, hard_header_len,
+ hard_iface->net_dev->hard_header_len);
+
+ needed_headroom = max_t(unsigned short, needed_headroom,
+ hard_iface->net_dev->needed_headroom);
+ }
+ rcu_read_unlock();
+
+ soft_iface->needed_headroom = needed_headroom;
+ soft_iface->hard_header_len = hard_header_len + batadv_max_header_len();
+}
+
int batadv_hardif_min_mtu(struct net_device *soft_iface)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
@@ -474,6 +501,8 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface
*hard_iface,
"Not using interface %s (retrying later): interface
not active\n",
hard_iface->net_dev->name);
+ batadv_hardif_recalc_headroom(soft_iface);
+
/* begin scheduling originator messages on that interface */
batadv_schedule_bat_ogm(hard_iface);
@@ -495,6 +524,7 @@ void batadv_hardif_disable_interface(struct
batadv_hard_iface *hard_iface,
{
struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
struct batadv_hard_iface *primary_if = NULL;
+ struct net_device *soft_iface;
if (hard_iface->if_status == BATADV_IF_ACTIVE)
batadv_hardif_deactivate_interface(hard_iface);
@@ -529,16 +559,18 @@ void batadv_hardif_disable_interface(struct
batadv_hard_iface *hard_iface,
dev_put(hard_iface->soft_iface);
netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
+ soft_iface = hard_iface->soft_iface;
+ hard_iface->soft_iface = NULL;
+ batadv_hardif_recalc_headroom(soft_iface);
/* nobody uses this interface anymore */
if (!bat_priv->num_ifaces) {
batadv_gw_check_client_stop(bat_priv);
if (autodel == BATADV_IF_CLEANUP_AUTO)
- batadv_softif_destroy_sysfs(hard_iface->soft_iface);
+ batadv_softif_destroy_sysfs(soft_iface);
}
- hard_iface->soft_iface = NULL;
batadv_hardif_free_ref(hard_iface);
out:
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 36b23f31df2a..b4c110791203 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -948,7 +948,7 @@ static void batadv_softif_init_early(struct net_device *dev)
*/
dev->mtu = ETH_DATA_LEN;
/* reserve more space in the skbuff for our header */
- dev->hard_header_len = batadv_max_header_len();
+ dev->hard_header_len = ETH_HLEN + batadv_max_header_len();
/* generate random address */
eth_hw_addr_random(dev);
--
2.5.0
