[B.A.T.M.A.N.] [PATCH 4/8] batman-adv: Make orig_node->router an rcu protected pointer

From: Linus Lüssing linus.luessing@web.de

The rcu protected macros rcu_dereference() and rcu_assign_pointer() for the orig_node->router need to be used, as well as spin/rcu locking. Otherwise we might end up using a router pointer pointing to already freed memory.

Therefore this commit introduces the safe getter method orig_node_get_router().

Signed-off-by: Linus Lüssing linus.luessing@web.de Signed-off-by: Marek Lindner lindner_marek@yahoo.de Signed-off-by: Sven Eckelmann sven@narfation.org --- net/batman-adv/gateway_client.c | 80 ++++++++++------- net/batman-adv/icmp_socket.c | 18 +--- net/batman-adv/originator.c | 37 ++++++-- net/batman-adv/originator.h | 1 + net/batman-adv/routing.c | 194 +++++++++++++++++++-------------------- net/batman-adv/send.c | 19 +++-- net/batman-adv/types.h | 4 +- net/batman-adv/vis.c | 91 +++++++++--------- 8 files changed, 232 insertions(+), 212 deletions(-)

diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c index 879ac15..42a8a7b 100644 --- a/net/batman-adv/gateway_client.c +++ b/net/batman-adv/gateway_client.c @@ -98,6 +98,7 @@ void gw_election(struct bat_priv *bat_priv) { struct hlist_node *node; struct gw_node *gw_node, *curr_gw, *curr_gw_tmp = NULL; + struct neigh_node *router; uint8_t max_tq = 0; uint32_t max_gw_factor = 0, tmp_gw_factor = 0; int down, up; @@ -133,10 +134,11 @@ void gw_election(struct bat_priv *bat_priv) }

hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) { - if (!gw_node->orig_node->router) + if (gw_node->deleted) continue;

- if (gw_node->deleted) + router = orig_node_get_router(gw_node->orig_node); + if (!router) continue;

switch (atomic_read(&bat_priv->gw_sel_class)) { @@ -144,15 +146,14 @@ void gw_election(struct bat_priv *bat_priv) gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up);

- tmp_gw_factor = (gw_node->orig_node->router->tq_avg * - gw_node->orig_node->router->tq_avg * + tmp_gw_factor = (router->tq_avg * router->tq_avg * down * 100 * 100) / (TQ_LOCAL_WINDOW_SIZE * TQ_LOCAL_WINDOW_SIZE * 64);

if ((tmp_gw_factor > max_gw_factor) || ((tmp_gw_factor == max_gw_factor) && - (gw_node->orig_node->router->tq_avg > max_tq))) + (router->tq_avg > max_tq))) curr_gw_tmp = gw_node; break;

@@ -164,19 +165,25 @@ void gw_election(struct bat_priv *bat_priv) * soon as a better gateway appears which has * $routing_class more tq points) **/ - if (gw_node->orig_node->router->tq_avg > max_tq) + if (router->tq_avg > max_tq) curr_gw_tmp = gw_node; break; }

- if (gw_node->orig_node->router->tq_avg > max_tq) - max_tq = gw_node->orig_node->router->tq_avg; + if (router->tq_avg > max_tq) + max_tq = router->tq_avg;

if (tmp_gw_factor > max_gw_factor) max_gw_factor = tmp_gw_factor; + + neigh_node_free_ref(router); }

if (curr_gw != curr_gw_tmp) { + router = orig_node_get_router(curr_gw_tmp->orig_node); + if (!router) + goto out; + if ((curr_gw) && (!curr_gw_tmp)) bat_dbg(DBG_BATMAN, bat_priv, "Removing selected gateway - " @@ -187,45 +194,47 @@ void gw_election(struct bat_priv *bat_priv) "(gw_flags: %i, tq: %i)\n", curr_gw_tmp->orig_node->orig, curr_gw_tmp->orig_node->gw_flags, - curr_gw_tmp->orig_node->router->tq_avg); + router->tq_avg); else bat_dbg(DBG_BATMAN, bat_priv, "Changing route to gateway %pM " "(gw_flags: %i, tq: %i)\n", curr_gw_tmp->orig_node->orig, curr_gw_tmp->orig_node->gw_flags, - curr_gw_tmp->orig_node->router->tq_avg); + router->tq_avg);

+ neigh_node_free_ref(router); gw_select(bat_priv, curr_gw_tmp); }

+out: rcu_read_unlock(); }

void gw_check_election(struct bat_priv *bat_priv, struct orig_node *orig_node) { struct orig_node *curr_gw_orig; + struct neigh_node *router_gw = NULL, *router_orig = NULL; uint8_t gw_tq_avg, orig_tq_avg;

curr_gw_orig = gw_get_selected(bat_priv); if (!curr_gw_orig) goto deselect;

- rcu_read_lock(); - if (!curr_gw_orig->router) - goto deselect_rcu; + router_gw = orig_node_get_router(curr_gw_orig); + if (!router_gw) + goto deselect;

/* this node already is the gateway */ if (curr_gw_orig == orig_node) - goto out_rcu; + goto out;

- if (!orig_node->router) - goto out_rcu; + router_orig = orig_node_get_router(orig_node); + if (!router_orig) + goto out;

- gw_tq_avg = curr_gw_orig->router->tq_avg; - rcu_read_unlock(); - - orig_tq_avg = orig_node->router->tq_avg; + gw_tq_avg = router_gw->tq_avg; + orig_tq_avg = router_orig->tq_avg;

/* the TQ value has to be better */ if (orig_tq_avg < gw_tq_avg) @@ -243,18 +252,16 @@ void gw_check_election(struct bat_priv *bat_priv, struct orig_node *orig_node) "Restarting gateway selection: better gateway found (tq curr: " "%i, tq new: %i)\n", gw_tq_avg, orig_tq_avg); - goto deselect;

-out_rcu: - rcu_read_unlock(); - goto out; -deselect_rcu: - rcu_read_unlock(); deselect: gw_deselect(bat_priv); out: if (curr_gw_orig) orig_node_free_ref(curr_gw_orig); + if (router_gw) + neigh_node_free_ref(router_gw); + if (router_orig) + neigh_node_free_ref(router_orig);

return; } @@ -362,23 +369,30 @@ void gw_node_purge(struct bat_priv *bat_priv) spin_unlock_bh(&bat_priv->gw_list_lock); }

+/** + * fails if orig_node has no router + */ static int _write_buffer_text(struct bat_priv *bat_priv, struct seq_file *seq, struct gw_node *gw_node) { struct gw_node *curr_gw; - int down, up, ret; + struct neigh_node *router; + int down, up, ret = -1;

gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up);

+ router = orig_node_get_router(gw_node->orig_node); + if (!router) + goto out; + rcu_read_lock(); curr_gw = rcu_dereference(bat_priv->curr_gw);

ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n", (curr_gw == gw_node ? "=>" : " "), gw_node->orig_node->orig, - gw_node->orig_node->router->tq_avg, - gw_node->orig_node->router->addr, - gw_node->orig_node->router->if_incoming->net_dev->name, + router->tq_avg, router->addr, + router->if_incoming->net_dev->name, gw_node->orig_node->gw_flags, (down > 2048 ? down / 1024 : down), (down > 2048 ? "MBit" : "KBit"), @@ -386,6 +400,8 @@ static int _write_buffer_text(struct bat_priv *bat_priv, (up > 2048 ? "MBit" : "KBit"));

rcu_read_unlock(); + neigh_node_free_ref(router); +out: return ret; }

@@ -423,10 +439,10 @@ int gw_client_seq_print_text(struct seq_file *seq, void *offset) if (gw_node->deleted) continue;

- if (!gw_node->orig_node->router) + /* fails if orig_node has no router */ + if (_write_buffer_text(bat_priv, seq, gw_node) < 0) continue;

- _write_buffer_text(bat_priv, seq, gw_node); gw_count++; } rcu_read_unlock(); diff --git a/net/batman-adv/icmp_socket.c b/net/batman-adv/icmp_socket.c index 34ce56c..49079c2 100644 --- a/net/batman-adv/icmp_socket.c +++ b/net/batman-adv/icmp_socket.c @@ -218,23 +218,13 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff, if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE) goto dst_unreach;

- rcu_read_lock(); orig_node = orig_hash_find(bat_priv, icmp_packet->dst); - if (!orig_node) - goto unlock; - - neigh_node = orig_node->router; + goto dst_unreach;

+ neigh_node = orig_node_get_router(orig_node); if (!neigh_node) - goto unlock; - - if (!atomic_inc_not_zero(&neigh_node->refcount)) { - neigh_node = NULL; - goto unlock; - } - - rcu_read_unlock(); + goto dst_unreach;

if (!neigh_node->if_incoming) goto dst_unreach; @@ -252,8 +242,6 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff, send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); goto out;

-unlock: - rcu_read_unlock(); dst_unreach: icmp_packet->msg_type = DESTINATION_UNREACHABLE; bat_socket_add_packet(socket_client, icmp_packet, packet_len); diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 0b91330..b4cfe36 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -70,6 +70,21 @@ void neigh_node_free_ref(struct neigh_node *neigh_node) call_rcu(&neigh_node->rcu, neigh_node_free_rcu); }

+/* increases the refcounter of a found router */ +struct neigh_node *orig_node_get_router(struct orig_node *orig_node) +{ + struct neigh_node *router; + + rcu_read_lock(); + router = rcu_dereference(orig_node->router); + + if (router && !atomic_inc_not_zero(&router->refcount)) + router = NULL; + + rcu_read_unlock(); + return router; +} + struct neigh_node *create_neighbor(struct orig_node *orig_node, struct orig_node *orig_neigh_node, uint8_t *neigh, @@ -390,7 +405,7 @@ int orig_seq_print_text(struct seq_file *seq, void *offset) struct hlist_node *node, *node_tmp; struct hlist_head *head; struct orig_node *orig_node; - struct neigh_node *neigh_node; + struct neigh_node *neigh_node, *neigh_node_tmp; int batman_count = 0; int last_seen_secs; int last_seen_msecs; @@ -421,37 +436,41 @@ int orig_seq_print_text(struct seq_file *seq, void *offset)

rcu_read_lock(); hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) { - if (!orig_node->router) + neigh_node = orig_node_get_router(orig_node); + if (!neigh_node) continue;

- if (orig_node->router->tq_avg == 0) - continue; + if (neigh_node->tq_avg == 0) + goto next;

last_seen_secs = jiffies_to_msecs(jiffies - orig_node->last_valid) / 1000; last_seen_msecs = jiffies_to_msecs(jiffies - orig_node->last_valid) % 1000;

- neigh_node = orig_node->router; seq_printf(seq, "%pM %4i.%03is (%3i) %pM [%10s]:", orig_node->orig, last_seen_secs, last_seen_msecs, neigh_node->tq_avg, neigh_node->addr, neigh_node->if_incoming->net_dev->name);

- hlist_for_each_entry_rcu(neigh_node, node_tmp, + hlist_for_each_entry_rcu(neigh_node_tmp, node_tmp, &orig_node->neigh_list, list) { - seq_printf(seq, " %pM (%3i)", neigh_node->addr, - neigh_node->tq_avg); + seq_printf(seq, " %pM (%3i)", + neigh_node_tmp->addr, + neigh_node_tmp->tq_avg); }

seq_printf(seq, "\n"); batman_count++; + +next: + neigh_node_free_ref(neigh_node); } rcu_read_unlock(); }

- if ((batman_count == 0)) + if (batman_count == 0) seq_printf(seq, "No batman nodes in range ...\n");

return 0; diff --git a/net/batman-adv/originator.h b/net/batman-adv/originator.h index 5cc0110..e1d641f 100644 --- a/net/batman-adv/originator.h +++ b/net/batman-adv/originator.h @@ -34,6 +34,7 @@ struct neigh_node *create_neighbor(struct orig_node *orig_node, uint8_t *neigh, struct hard_iface *if_incoming); void neigh_node_free_ref(struct neigh_node *neigh_node); +struct neigh_node *orig_node_get_router(struct orig_node *orig_node); int orig_seq_print_text(struct seq_file *seq, void *offset); int orig_hash_add_if(struct hard_iface *hard_iface, int max_if_num); int orig_hash_del_if(struct hard_iface *hard_iface, int max_if_num); diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index f212abe..b7d43ca 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -87,18 +87,20 @@ static void update_route(struct bat_priv *bat_priv, struct neigh_node *neigh_node, unsigned char *hna_buff, int hna_buff_len) { - struct neigh_node *neigh_node_tmp; + struct neigh_node *curr_router; + + curr_router = orig_node_get_router(orig_node);

/* route deleted */ - if ((orig_node->router) && (!neigh_node)) { + if ((curr_router) && (!neigh_node)) {

bat_dbg(DBG_ROUTES, bat_priv, "Deleting route towards: %pM\n", orig_node->orig); hna_global_del_orig(bat_priv, orig_node, "originator timed out");

- /* route added */ - } else if ((!orig_node->router) && (neigh_node)) { + /* route added */ + } else if ((!curr_router) && (neigh_node)) {

bat_dbg(DBG_ROUTES, bat_priv, "Adding route towards: %pM (via %pM)\n", @@ -106,21 +108,29 @@ static void update_route(struct bat_priv *bat_priv, hna_global_add_orig(bat_priv, orig_node, hna_buff, hna_buff_len);

- /* route changed */ + /* route changed */ } else { bat_dbg(DBG_ROUTES, bat_priv, "Changing route towards: %pM " "(now via %pM - was via %pM)\n", orig_node->orig, neigh_node->addr, - orig_node->router->addr); + curr_router->addr); }

+ if (curr_router) + neigh_node_free_ref(curr_router); + + /* increase refcount of new best neighbor */ if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount)) neigh_node = NULL; - neigh_node_tmp = orig_node->router; - orig_node->router = neigh_node; - if (neigh_node_tmp) - neigh_node_free_ref(neigh_node_tmp); + + spin_lock_bh(&orig_node->neigh_list_lock); + rcu_assign_pointer(orig_node->router, neigh_node); + spin_unlock_bh(&orig_node->neigh_list_lock); + + /* decrease refcount of previous best neighbor */ + if (curr_router) + neigh_node_free_ref(curr_router); }

@@ -128,16 +138,23 @@ void update_routes(struct bat_priv *bat_priv, struct orig_node *orig_node, struct neigh_node *neigh_node, unsigned char *hna_buff, int hna_buff_len) { + struct neigh_node *router = NULL;

if (!orig_node) - return; + goto out;

- if (orig_node->router != neigh_node) + router = orig_node_get_router(orig_node); + + if (router != neigh_node) update_route(bat_priv, orig_node, neigh_node, hna_buff, hna_buff_len); /* may be just HNA changed */ else update_HNA(bat_priv, orig_node, hna_buff, hna_buff_len); + +out: + if (router) + neigh_node_free_ref(router); }

static int is_bidirectional_neigh(struct orig_node *orig_node, @@ -288,8 +305,8 @@ static void bonding_candidate_add(struct orig_node *orig_node, struct neigh_node *neigh_node) { struct hlist_node *node; - struct neigh_node *tmp_neigh_node; - uint8_t best_tq, interference_candidate = 0; + struct neigh_node *tmp_neigh_node, *router = NULL; + uint8_t interference_candidate = 0;

spin_lock_bh(&orig_node->neigh_list_lock);

@@ -298,13 +315,12 @@ static void bonding_candidate_add(struct orig_node *orig_node, neigh_node->orig_node->primary_addr)) goto candidate_del;

- if (!orig_node->router) + router = orig_node_get_router(orig_node); + if (!router) goto candidate_del;

- best_tq = orig_node->router->tq_avg; - /* ... and is good enough to be considered */ - if (neigh_node->tq_avg < best_tq - BONDING_TQ_THRESHOLD) + if (neigh_node->tq_avg < router->tq_avg - BONDING_TQ_THRESHOLD) goto candidate_del;

/** @@ -350,7 +366,9 @@ candidate_del:

out: spin_unlock_bh(&orig_node->neigh_list_lock); - return; + + if (router) + neigh_node_free_ref(router); }

/* copy primary address for bonding */ @@ -373,6 +391,7 @@ static void update_orig(struct bat_priv *bat_priv, char is_duplicate) { struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL; + struct neigh_node *router = NULL; struct orig_node *orig_node_tmp; struct hlist_node *node; int tmp_hna_buff_len; @@ -441,19 +460,18 @@ static void update_orig(struct bat_priv *bat_priv,

/* if this neighbor already is our next hop there is nothing * to change */ - if (orig_node->router == neigh_node) + router = orig_node_get_router(orig_node); + if (router == neigh_node) goto update_hna;

/* if this neighbor does not offer a better TQ we won't consider it */ - if ((orig_node->router) && - (orig_node->router->tq_avg > neigh_node->tq_avg)) + if (router && (router->tq_avg > neigh_node->tq_avg)) goto update_hna;

/* if the TQ is the same and the link not more symetric we * won't consider it either */ - if ((orig_node->router) && - (neigh_node->tq_avg == orig_node->router->tq_avg)) { - orig_node_tmp = orig_node->router->orig_node; + if (router && (neigh_node->tq_avg == router->tq_avg)) { + orig_node_tmp = router->orig_node; spin_lock_bh(&orig_node_tmp->ogm_cnt_lock); bcast_own_sum_orig = orig_node_tmp->bcast_own_sum[if_incoming->if_num]; @@ -474,7 +492,7 @@ static void update_orig(struct bat_priv *bat_priv, goto update_gw;

update_hna: - update_routes(bat_priv, orig_node, orig_node->router, + update_routes(bat_priv, orig_node, router, hna_buff, tmp_hna_buff_len);

update_gw: @@ -496,6 +514,8 @@ unlock: out: if (neigh_node) neigh_node_free_ref(neigh_node); + if (router) + neigh_node_free_ref(router); }

/* checks whether the host restarted and is in the protection time. @@ -603,6 +623,8 @@ void receive_bat_packet(struct ethhdr *ethhdr, struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface); struct hard_iface *hard_iface; struct orig_node *orig_neigh_node, *orig_node; + struct neigh_node *router = NULL, *router_router = NULL; + struct neigh_node *orig_neigh_router = NULL; char has_directlink_flag; char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0; char is_broadcast = 0, is_bidirectional, is_single_hop_neigh; @@ -747,14 +769,15 @@ void receive_bat_packet(struct ethhdr *ethhdr, goto out; }

+ router = orig_node_get_router(orig_node); + if (router) + router_router = orig_node_get_router(router->orig_node); + /* avoid temporary routing loops */ - if ((orig_node->router) && - (orig_node->router->orig_node->router) && - (compare_eth(orig_node->router->addr, - batman_packet->prev_sender)) && + if (router && router_router && + (compare_eth(router->addr, batman_packet->prev_sender)) && !(compare_eth(batman_packet->orig, batman_packet->prev_sender)) && - (compare_eth(orig_node->router->addr, - orig_node->router->orig_node->router->addr))) { + (compare_eth(router->addr, router_router->addr))) { bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: ignoring all rebroadcast packets that " "may make me loop (sender: %pM)\n", ethhdr->h_source); @@ -769,9 +792,11 @@ void receive_bat_packet(struct ethhdr *ethhdr, if (!orig_neigh_node) goto out;

+ orig_neigh_router = orig_node_get_router(orig_neigh_node); + /* drop packet if sender is not a direct neighbor and if we * don't route towards it */ - if (!is_single_hop_neigh && (!orig_neigh_node->router)) { + if (!is_single_hop_neigh && (!orig_neigh_router)) { bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: OGM via unknown neighbor!\n"); goto out_neigh; @@ -825,6 +850,13 @@ out_neigh: if ((orig_neigh_node) && (!is_single_hop_neigh)) orig_node_free_ref(orig_neigh_node); out: + if (router) + neigh_node_free_ref(router); + if (router_router) + neigh_node_free_ref(router_router); + if (orig_neigh_router) + neigh_node_free_ref(orig_neigh_router); + orig_node_free_ref(orig_node); }

@@ -869,7 +901,7 @@ static int recv_my_icmp_packet(struct bat_priv *bat_priv, struct sk_buff *skb, size_t icmp_len) { struct orig_node *orig_node = NULL; - struct neigh_node *neigh_node = NULL; + struct neigh_node *router = NULL; struct icmp_packet_rr *icmp_packet; int ret = NET_RX_DROP;

@@ -886,23 +918,13 @@ static int recv_my_icmp_packet(struct bat_priv *bat_priv,

/* answer echo request (ping) */ /* get routing information */ - rcu_read_lock(); orig_node = orig_hash_find(bat_priv, icmp_packet->orig); - if (!orig_node) - goto unlock; + goto out;

- neigh_node = orig_node->router; - - if (!neigh_node) - goto unlock; - - if (!atomic_inc_not_zero(&neigh_node->refcount)) { - neigh_node = NULL; - goto unlock; - } - - rcu_read_unlock(); + router = orig_node_get_router(orig_node); + if (!router) + goto out;

/* create a copy of the skb, if needed, to modify it. */ if (skb_cow(skb, sizeof(struct ethhdr)) < 0) @@ -916,15 +938,12 @@ static int recv_my_icmp_packet(struct bat_priv *bat_priv, icmp_packet->msg_type = ECHO_REPLY; icmp_packet->ttl = TTL;

- send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); + send_skb_packet(skb, router->if_incoming, router->addr); ret = NET_RX_SUCCESS; - goto out;

-unlock: - rcu_read_unlock(); out: - if (neigh_node) - neigh_node_free_ref(neigh_node); + if (router) + neigh_node_free_ref(router); if (orig_node) orig_node_free_ref(orig_node); return ret; @@ -934,7 +953,7 @@ static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv, struct sk_buff *skb) { struct orig_node *orig_node = NULL; - struct neigh_node *neigh_node = NULL; + struct neigh_node *router = NULL; struct icmp_packet *icmp_packet; int ret = NET_RX_DROP;

@@ -952,23 +971,13 @@ static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv, goto out;

/* get routing information */ - rcu_read_lock(); orig_node = orig_hash_find(bat_priv, icmp_packet->orig); - if (!orig_node) - goto unlock; + goto out;

- neigh_node = orig_node->router; - - if (!neigh_node) - goto unlock; - - if (!atomic_inc_not_zero(&neigh_node->refcount)) { - neigh_node = NULL; - goto unlock; - } - - rcu_read_unlock(); + router = orig_node_get_router(orig_node); + if (!router) + goto out;

/* create a copy of the skb, if needed, to modify it. */ if (skb_cow(skb, sizeof(struct ethhdr)) < 0) @@ -982,15 +991,12 @@ static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv, icmp_packet->msg_type = TTL_EXCEEDED; icmp_packet->ttl = TTL;

- send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); + send_skb_packet(skb, router->if_incoming, router->addr); ret = NET_RX_SUCCESS; - goto out;

-unlock: - rcu_read_unlock(); out: - if (neigh_node) - neigh_node_free_ref(neigh_node); + if (router) + neigh_node_free_ref(router); if (orig_node) orig_node_free_ref(orig_node); return ret; @@ -1003,7 +1009,7 @@ int recv_icmp_packet(struct sk_buff *skb, struct hard_iface *recv_if) struct icmp_packet_rr *icmp_packet; struct ethhdr *ethhdr; struct orig_node *orig_node = NULL; - struct neigh_node *neigh_node = NULL; + struct neigh_node *router = NULL; int hdr_size = sizeof(struct icmp_packet); int ret = NET_RX_DROP;

@@ -1050,23 +1056,13 @@ int recv_icmp_packet(struct sk_buff *skb, struct hard_iface *recv_if) return recv_icmp_ttl_exceeded(bat_priv, skb);

/* get routing information */ - rcu_read_lock(); orig_node = orig_hash_find(bat_priv, icmp_packet->dst); - if (!orig_node) - goto unlock; + goto out;

- neigh_node = orig_node->router; - - if (!neigh_node) - goto unlock; - - if (!atomic_inc_not_zero(&neigh_node->refcount)) { - neigh_node = NULL; - goto unlock; - } - - rcu_read_unlock(); + router = orig_node_get_router(orig_node); + if (!router) + goto out;

/* create a copy of the skb, if needed, to modify it. */ if (skb_cow(skb, sizeof(struct ethhdr)) < 0) @@ -1078,15 +1074,12 @@ int recv_icmp_packet(struct sk_buff *skb, struct hard_iface *recv_if) icmp_packet->ttl--;

/* route it */ - send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); + send_skb_packet(skb, router->if_incoming, router->addr); ret = NET_RX_SUCCESS; - goto out;

-unlock: - rcu_read_unlock(); out: - if (neigh_node) - neigh_node_free_ref(neigh_node); + if (router) + neigh_node_free_ref(router); if (orig_node) orig_node_free_ref(orig_node); return ret; @@ -1208,7 +1201,8 @@ struct neigh_node *find_router(struct bat_priv *bat_priv, if (!orig_node) return NULL;

- if (!orig_node->router) + router = orig_node_get_router(orig_node); + if (!router) return NULL;

/* without bonding, the first node should @@ -1217,9 +1211,8 @@ struct neigh_node *find_router(struct bat_priv *bat_priv,

rcu_read_lock(); /* select default router to output */ - router = orig_node->router; - router_orig = orig_node->router->orig_node; - if (!router_orig || !atomic_inc_not_zero(&router->refcount)) { + router_orig = router->orig_node; + if (!router_orig) { rcu_read_unlock(); return NULL; } @@ -1251,7 +1244,6 @@ struct neigh_node *find_router(struct bat_priv *bat_priv, if (atomic_read(&primary_orig_node->bond_candidates) < 2) goto return_router;

- /* all nodes between should choose a candidate which * is is not on the interface where the packet came * in. */ diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c index d49e54d..e78670c 100644 --- a/net/batman-adv/send.c +++ b/net/batman-adv/send.c @@ -308,6 +308,7 @@ void schedule_forward_packet(struct orig_node *orig_node, struct hard_iface *if_incoming) { struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface); + struct neigh_node *router; unsigned char in_tq, in_ttl, tq_avg = 0; unsigned long send_time;

@@ -316,6 +317,8 @@ void schedule_forward_packet(struct orig_node *orig_node, return; }

+ router = orig_node_get_router(orig_node); + in_tq = batman_packet->tq; in_ttl = batman_packet->ttl;

@@ -324,20 +327,22 @@ void schedule_forward_packet(struct orig_node *orig_node,

/* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast * of our best tq value */ - if ((orig_node->router) && (orig_node->router->tq_avg != 0)) { + if (router && router->tq_avg != 0) {

/* rebroadcast ogm of best ranking neighbor as is */ - if (!compare_eth(orig_node->router->addr, ethhdr->h_source)) { - batman_packet->tq = orig_node->router->tq_avg; + if (!compare_eth(router->addr, ethhdr->h_source)) { + batman_packet->tq = router->tq_avg;

- if (orig_node->router->last_ttl) - batman_packet->ttl = orig_node->router->last_ttl - - 1; + if (router->last_ttl) + batman_packet->ttl = router->last_ttl - 1; }

- tq_avg = orig_node->router->tq_avg; + tq_avg = router->tq_avg; }

+ if (router) + neigh_node_free_ref(router); + /* apply hop penalty */ batman_packet->tq = hop_penalty(batman_packet->tq, bat_priv);

diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 83445cf..1854cbb 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -67,7 +67,7 @@ struct hard_iface { struct orig_node { uint8_t orig[ETH_ALEN]; uint8_t primary_addr[ETH_ALEN]; - struct neigh_node *router; + struct neigh_node __rcu *router; /* rcu protected pointer */ unsigned long *bcast_own; uint8_t *bcast_own_sum; unsigned long last_valid; @@ -83,7 +83,7 @@ struct orig_node { uint32_t last_bcast_seqno; struct hlist_head neigh_list; struct list_head frag_list; - spinlock_t neigh_list_lock; /* protects neighbor list */ + spinlock_t neigh_list_lock; /* protects neigh_list and router */ atomic_t refcount; struct rcu_head rcu; struct hlist_node hash_entry; diff --git a/net/batman-adv/vis.c b/net/batman-adv/vis.c index f90212f..d4cc4f5 100644 --- a/net/batman-adv/vis.c +++ b/net/batman-adv/vis.c @@ -558,6 +558,7 @@ static int find_best_vis_server(struct bat_priv *bat_priv, struct vis_info *info) { struct hashtable_t *hash = bat_priv->orig_hash; + struct neigh_node *router; struct hlist_node *node; struct hlist_head *head; struct orig_node *orig_node; @@ -571,13 +572,17 @@ static int find_best_vis_server(struct bat_priv *bat_priv,

rcu_read_lock(); hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) { - if ((orig_node) && (orig_node->router) && - (orig_node->flags & VIS_SERVER) && - (orig_node->router->tq_avg > best_tq)) { - best_tq = orig_node->router->tq_avg; + router = orig_node_get_router(orig_node); + if (!router) + continue; + + if ((orig_node->flags & VIS_SERVER) && + (router->tq_avg > best_tq)) { + best_tq = router->tq_avg; memcpy(packet->target_orig, orig_node->orig, ETH_ALEN); } + neigh_node_free_ref(router); } rcu_read_unlock(); } @@ -605,7 +610,7 @@ static int generate_vis_packet(struct bat_priv *bat_priv) struct hlist_node *node; struct hlist_head *head; struct orig_node *orig_node; - struct neigh_node *neigh_node; + struct neigh_node *router; struct vis_info *info = (struct vis_info *)bat_priv->my_vis_info; struct vis_packet *packet = (struct vis_packet *)info->skb_packet->data; struct vis_info_entry *entry; @@ -633,30 +638,32 @@ static int generate_vis_packet(struct bat_priv *bat_priv)

rcu_read_lock(); hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) { - neigh_node = orig_node->router; - - if (!neigh_node) + router = orig_node_get_router(orig_node); + if (!router) continue;

- if (!compare_eth(neigh_node->addr, orig_node->orig)) - continue; + if (!compare_eth(router->addr, orig_node->orig)) + goto next;

- if (neigh_node->if_incoming->if_status != IF_ACTIVE) - continue; + if (router->if_incoming->if_status != IF_ACTIVE) + goto next;

- if (neigh_node->tq_avg < 1) - continue; + if (router->tq_avg < 1) + goto next;

/* fill one entry into buffer. */ entry = (struct vis_info_entry *) skb_put(info->skb_packet, sizeof(*entry)); memcpy(entry->src, - neigh_node->if_incoming->net_dev->dev_addr, + router->if_incoming->net_dev->dev_addr, ETH_ALEN); memcpy(entry->dest, orig_node->orig, ETH_ALEN); - entry->quality = neigh_node->tq_avg; + entry->quality = router->tq_avg; packet->entries++;

+next: + neigh_node_free_ref(router); + if (vis_packet_full(info)) goto unlock; } @@ -725,6 +732,7 @@ static void purge_vis_packets(struct bat_priv *bat_priv) static void broadcast_vis_packet(struct bat_priv *bat_priv, struct vis_info *info) { + struct neigh_node *router; struct hashtable_t *hash = bat_priv->orig_hash; struct hlist_node *node; struct hlist_head *head; @@ -745,19 +753,26 @@ static void broadcast_vis_packet(struct bat_priv *bat_priv, rcu_read_lock(); hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) { /* if it's a vis server and reachable, send it. */ - if ((!orig_node) || (!orig_node->router)) - continue; if (!(orig_node->flags & VIS_SERVER)) continue; + + router = orig_node_get_router(orig_node); + if (!router) + continue; + /* don't send it if we already received the packet from - * this node. */ + * this node. */ if (recv_list_is_in(bat_priv, &info->recv_list, - orig_node->orig)) + orig_node->orig)) { + neigh_node_free_ref(router); continue; + }

memcpy(packet->target_orig, orig_node->orig, ETH_ALEN); - hard_iface = orig_node->router->if_incoming; - memcpy(dstaddr, orig_node->router->addr, ETH_ALEN); + hard_iface = router->if_incoming; + memcpy(dstaddr, router->addr, ETH_ALEN); + + neigh_node_free_ref(router);

skb = skb_clone(info->skb_packet, GFP_ATOMIC); if (skb) @@ -772,45 +787,29 @@ static void unicast_vis_packet(struct bat_priv *bat_priv, struct vis_info *info) { struct orig_node *orig_node; - struct neigh_node *neigh_node = NULL; + struct neigh_node *router = NULL; struct sk_buff *skb; struct vis_packet *packet;

packet = (struct vis_packet *)info->skb_packet->data;

- rcu_read_lock(); orig_node = orig_hash_find(bat_priv, packet->target_orig); - if (!orig_node) - goto unlock; + goto out;

- neigh_node = orig_node->router; - - if (!neigh_node) - goto unlock; - - if (!atomic_inc_not_zero(&neigh_node->refcount)) { - neigh_node = NULL; - goto unlock; - } - - rcu_read_unlock(); + router = orig_node_get_router(orig_node); + if (!router) + goto out;

skb = skb_clone(info->skb_packet, GFP_ATOMIC); if (skb) - send_skb_packet(skb, neigh_node->if_incoming, - neigh_node->addr); + send_skb_packet(skb, router->if_incoming, router->addr);

- goto out; - -unlock: - rcu_read_unlock(); out: - if (neigh_node) - neigh_node_free_ref(neigh_node); + if (router) + neigh_node_free_ref(router); if (orig_node) orig_node_free_ref(orig_node); - return; }

/* only send one vis packet. called from send_vis_packets() */