diff options
Diffstat (limited to 'net/batman-adv/routing.c')
| -rw-r--r-- | net/batman-adv/routing.c | 166 |
1 files changed, 97 insertions, 69 deletions
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index e4f2646d9246..6c2901a86230 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2007-2015 B.A.T.M.A.N. contributors: +/* Copyright (C) 2007-2016 B.A.T.M.A.N. contributors: * * Marek Lindner, Simon Wunderlich * @@ -25,6 +25,7 @@ #include <linux/etherdevice.h> #include <linux/if_ether.h> #include <linux/jiffies.h> +#include <linux/kref.h> #include <linux/netdevice.h> #include <linux/printk.h> #include <linux/rculist.h> @@ -72,7 +73,7 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, rcu_read_lock(); curr_router = rcu_dereference(orig_ifinfo->router); - if (curr_router && !atomic_inc_not_zero(&curr_router->refcount)) + if (curr_router && !kref_get_unless_zero(&curr_router->refcount)) curr_router = NULL; rcu_read_unlock(); @@ -97,20 +98,29 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, } if (curr_router) - batadv_neigh_node_free_ref(curr_router); + batadv_neigh_node_put(curr_router); + + spin_lock_bh(&orig_node->neigh_list_lock); + /* curr_router used earlier may not be the current orig_ifinfo->router + * anymore because it was dereferenced outside of the neigh_list_lock + * protected region. After the new best neighbor has replace the current + * best neighbor the reference counter needs to decrease. Consequently, + * the code needs to ensure the curr_router variable contains a pointer + * to the replaced best neighbor. + */ + curr_router = rcu_dereference_protected(orig_ifinfo->router, true); /* increase refcount of new best neighbor */ - if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount)) - neigh_node = NULL; + if (neigh_node) + kref_get(&neigh_node->refcount); - spin_lock_bh(&orig_node->neigh_list_lock); rcu_assign_pointer(orig_ifinfo->router, neigh_node); spin_unlock_bh(&orig_node->neigh_list_lock); - batadv_orig_ifinfo_free_ref(orig_ifinfo); + batadv_orig_ifinfo_put(orig_ifinfo); /* decrease refcount of previous best neighbor */ if (curr_router) - batadv_neigh_node_free_ref(curr_router); + batadv_neigh_node_put(curr_router); } /** @@ -137,29 +147,43 @@ void batadv_update_route(struct batadv_priv *bat_priv, out: if (router) - batadv_neigh_node_free_ref(router); + batadv_neigh_node_put(router); } -/* checks whether the host restarted and is in the protection time. - * returns: - * 0 if the packet is to be accepted - * 1 if the packet is to be ignored. +/** + * batadv_window_protected - checks whether the host restarted and is in the + * protection time. + * @bat_priv: the bat priv with all the soft interface information + * @seq_num_diff: difference between the current/received sequence number and + * the last sequence number + * @seq_old_max_diff: maximum age of sequence number not considered as restart + * @last_reset: jiffies timestamp of the last reset, will be updated when reset + * is detected + * @protection_started: is set to true if the protection window was started, + * doesn't change otherwise. + * + * Return: + * false if the packet is to be accepted. + * true if the packet is to be ignored. */ -int batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff, - unsigned long *last_reset) +bool batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff, + s32 seq_old_max_diff, unsigned long *last_reset, + bool *protection_started) { - if (seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE || + if (seq_num_diff <= -seq_old_max_diff || seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) { if (!batadv_has_timed_out(*last_reset, BATADV_RESET_PROTECTION_MS)) - return 1; + return true; *last_reset = jiffies; + if (protection_started) + *protection_started = true; batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "old packet received, start protection\n"); } - return 0; + return false; } bool batadv_check_management_packet(struct sk_buff *skb, @@ -198,7 +222,7 @@ bool batadv_check_management_packet(struct sk_buff *skb, * @bat_priv: the bat priv with all the soft interface information * @skb: icmp packet to process * - * Returns NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP + * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP * otherwise. */ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv, @@ -254,9 +278,9 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv, } out: if (primary_if) - batadv_hardif_free_ref(primary_if); + batadv_hardif_put(primary_if); if (orig_node) - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); return ret; } @@ -302,9 +326,9 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv, out: if (primary_if) - batadv_hardif_free_ref(primary_if); + batadv_hardif_put(primary_if); if (orig_node) - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); return ret; } @@ -350,6 +374,7 @@ int batadv_recv_icmp_packet(struct sk_buff *skb, if (skb_cow(skb, ETH_HLEN) < 0) goto out; + ethhdr = eth_hdr(skb); icmph = (struct batadv_icmp_header *)skb->data; icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmph; if (icmp_packet_rr->rr_cur >= BATADV_RR_LEN) @@ -388,7 +413,7 @@ int batadv_recv_icmp_packet(struct sk_buff *skb, out: if (orig_node) - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); return ret; } @@ -398,10 +423,11 @@ out: * @skb: packet to check * @hdr_size: size of header to pull * - * Check for short header and bad addresses in given packet. Returns negative - * value when check fails and 0 otherwise. The negative value depends on the - * reason: -ENODATA for bad header, -EBADR for broadcast destination or source, - * and -EREMOTE for non-local (other host) destination. + * Check for short header and bad addresses in given packet. + * + * Return: negative value when check fails and 0 otherwise. The negative value + * depends on the reason: -ENODATA for bad header, -EBADR for broadcast + * destination or source, and -EREMOTE for non-local (other host) destination. */ static int batadv_check_unicast_packet(struct batadv_priv *bat_priv, struct sk_buff *skb, int hdr_size) @@ -435,7 +461,7 @@ static int batadv_check_unicast_packet(struct batadv_priv *bat_priv, * @orig_node: the destination node * @recv_if: pointer to interface this packet was received on * - * Returns the router which should be used for this orig_node on + * Return: the router which should be used for this orig_node on * this interface, or NULL if not available. */ struct batadv_neigh_node * @@ -482,14 +508,14 @@ batadv_find_router(struct batadv_priv *bat_priv, hlist_for_each_entry_rcu(cand, &orig_node->ifinfo_list, list) { /* acquire some structures and references ... */ - if (!atomic_inc_not_zero(&cand->refcount)) + if (!kref_get_unless_zero(&cand->refcount)) continue; cand_router = rcu_dereference(cand->router); if (!cand_router) goto next; - if (!atomic_inc_not_zero(&cand_router->refcount)) { + if (!kref_get_unless_zero(&cand_router->refcount)) { cand_router = NULL; goto next; } @@ -508,8 +534,8 @@ batadv_find_router(struct batadv_priv *bat_priv, /* mark the first possible candidate */ if (!first_candidate) { - atomic_inc(&cand_router->refcount); - atomic_inc(&cand->refcount); + kref_get(&cand_router->refcount); + kref_get(&cand->refcount); first_candidate = cand; first_candidate_router = cand_router; } @@ -529,16 +555,16 @@ batadv_find_router(struct batadv_priv *bat_priv, next: /* free references */ if (cand_router) { - batadv_neigh_node_free_ref(cand_router); + batadv_neigh_node_put(cand_router); cand_router = NULL; } - batadv_orig_ifinfo_free_ref(cand); + batadv_orig_ifinfo_put(cand); } rcu_read_unlock(); /* last_bonding_candidate is reset below, remove the old reference. */ if (orig_node->last_bonding_candidate) - batadv_orig_ifinfo_free_ref(orig_node->last_bonding_candidate); + batadv_orig_ifinfo_put(orig_node->last_bonding_candidate); /* After finding candidates, handle the three cases: * 1) there is a next candidate, use that @@ -546,17 +572,17 @@ next: * 3) there is no candidate at all, return the default router */ if (next_candidate) { - batadv_neigh_node_free_ref(router); + batadv_neigh_node_put(router); /* remove references to first candidate, we don't need it. */ if (first_candidate) { - batadv_neigh_node_free_ref(first_candidate_router); - batadv_orig_ifinfo_free_ref(first_candidate); + batadv_neigh_node_put(first_candidate_router); + batadv_orig_ifinfo_put(first_candidate); } router = next_candidate_router; orig_node->last_bonding_candidate = next_candidate; } else if (first_candidate) { - batadv_neigh_node_free_ref(router); + batadv_neigh_node_put(router); /* refcounting has already been done in the loop above. */ router = first_candidate_router; @@ -576,6 +602,7 @@ static int batadv_route_unicast_packet(struct sk_buff *skb, struct batadv_unicast_packet *unicast_packet; struct ethhdr *ethhdr = eth_hdr(skb); int res, hdr_len, ret = NET_RX_DROP; + unsigned int len; unicast_packet = (struct batadv_unicast_packet *)skb->data; @@ -616,6 +643,7 @@ static int batadv_route_unicast_packet(struct sk_buff *skb, if (hdr_len > 0) batadv_skb_set_priority(skb, hdr_len); + len = skb->len; res = batadv_send_skb_to_orig(skb, orig_node, recv_if); /* translate transmit result into receive result */ @@ -623,7 +651,7 @@ static int batadv_route_unicast_packet(struct sk_buff *skb, /* skb was transmitted and consumed */ batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD); batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES, - skb->len + ETH_HLEN); + len + ETH_HLEN); ret = NET_RX_SUCCESS; } else if (res == NET_XMIT_POLICED) { @@ -633,7 +661,7 @@ static int batadv_route_unicast_packet(struct sk_buff *skb, out: if (orig_node) - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); return ret; } @@ -648,7 +676,7 @@ out: * the new corresponding information (originator address where the destination * client currently is and its known TTVN) * - * Returns true if the packet header has been updated, false otherwise + * Return: true if the packet header has been updated, false otherwise */ static bool batadv_reroute_unicast_packet(struct batadv_priv *bat_priv, @@ -686,15 +714,16 @@ batadv_reroute_unicast_packet(struct batadv_priv *bat_priv, ret = true; out: if (primary_if) - batadv_hardif_free_ref(primary_if); + batadv_hardif_put(primary_if); if (orig_node) - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); return ret; } -static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, - struct sk_buff *skb, int hdr_len) { +static bool batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, + struct sk_buff *skb, int hdr_len) +{ struct batadv_unicast_packet *unicast_packet; struct batadv_hard_iface *primary_if; struct batadv_orig_node *orig_node; @@ -705,11 +734,11 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, /* check if there is enough data before accessing it */ if (!pskb_may_pull(skb, hdr_len + ETH_HLEN)) - return 0; + return false; /* create a copy of the skb (in case of for re-routing) to modify it. */ if (skb_cow(skb, sizeof(*unicast_packet)) < 0) - return 0; + return false; unicast_packet = (struct batadv_unicast_packet *)skb->data; vid = batadv_get_vid(skb, hdr_len); @@ -733,7 +762,7 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, * table. If not, let the packet go untouched anyway because * there is nothing the node can do */ - return 1; + return true; } /* retrieve the TTVN known by this node for the packet destination. This @@ -749,10 +778,10 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, * not be possible to deliver it */ if (!orig_node) - return 0; + return false; curr_ttvn = (u8)atomic_read(&orig_node->last_ttvn); - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); } /* check if the TTVN contained in the packet is fresher than what the @@ -760,7 +789,7 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, */ is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn); if (!is_old_ttvn) - return 1; + return true; old_ttvn = unicast_packet->ttvn; /* the packet was forged based on outdated network information. Its @@ -773,7 +802,7 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n", unicast_packet->dest, ethhdr->h_dest, old_ttvn, curr_ttvn); - return 1; + return true; } /* the packet has not been re-routed: either the destination is @@ -781,22 +810,22 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, * it is possible to drop the packet */ if (!batadv_is_my_client(bat_priv, ethhdr->h_dest, vid)) - return 0; + return false; /* update the header in order to let the packet be delivered to this * node's soft interface */ primary_if = batadv_primary_if_get_selected(bat_priv); if (!primary_if) - return 0; + return false; ether_addr_copy(unicast_packet->dest, primary_if->net_dev->dev_addr); - batadv_hardif_free_ref(primary_if); + batadv_hardif_put(primary_if); unicast_packet->ttvn = curr_ttvn; - return 1; + return true; } /** @@ -805,7 +834,7 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, * @skb: unicast tvlv packet to process * @recv_if: pointer to interface this packet was received on * - * Returns NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP + * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP * otherwise. */ int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb, @@ -887,12 +916,12 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, hdr_size)) goto rx_success; - batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size, + batadv_interface_rx(recv_if->soft_iface, skb, hdr_size, orig_node); rx_success: if (orig_node) - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); return NET_RX_SUCCESS; } @@ -904,9 +933,8 @@ rx_success: * batadv_recv_unicast_tvlv - receive and process unicast tvlv packets * @skb: unicast tvlv packet to process * @recv_if: pointer to interface this packet was received on - * @dst_addr: the payload destination * - * Returns NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP + * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP * otherwise. */ int batadv_recv_unicast_tvlv(struct sk_buff *skb, @@ -960,7 +988,7 @@ int batadv_recv_unicast_tvlv(struct sk_buff *skb, * the assembled packet will exceed our MTU; 2) Buffer fragment, if we till * lack further fragments; 3) Merge fragments, if we have all needed parts. * - * Return NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS otherwise. + * Return: NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS otherwise. */ int batadv_recv_frag_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if) @@ -1004,7 +1032,7 @@ int batadv_recv_frag_packet(struct sk_buff *skb, out: if (orig_node_src) - batadv_orig_node_free_ref(orig_node_src); + batadv_orig_node_put(orig_node_src); return ret; } @@ -1065,7 +1093,8 @@ int batadv_recv_bcast_packet(struct sk_buff *skb, /* check whether the packet is old and the host just restarted. */ if (batadv_window_protected(bat_priv, seq_diff, - &orig_node->bcast_seqno_reset)) + BATADV_BCAST_MAX_AGE, + &orig_node->bcast_seqno_reset, NULL)) goto spin_unlock; /* mark broadcast in flood history, update window position @@ -1097,8 +1126,7 @@ int batadv_recv_bcast_packet(struct sk_buff *skb, goto rx_success; /* broadcast for me */ - batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size, - orig_node); + batadv_interface_rx(recv_if->soft_iface, skb, hdr_size, orig_node); rx_success: ret = NET_RX_SUCCESS; @@ -1108,6 +1136,6 @@ spin_unlock: spin_unlock_bh(&orig_node->bcast_seqno_lock); out: if (orig_node) - batadv_orig_node_free_ref(orig_node); + batadv_orig_node_put(orig_node); return ret; } |