From 0ede9f41b217d8982ab426e3c8c1b692a280a16f Mon Sep 17 00:00:00 2001 From: Marek Lindner Date: Tue, 25 Jan 2011 21:52:10 +0000 Subject: [PATCH] batman-adv: protect bit operations to count OGMs with spinlock MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Reported-by: Linus Lüssing Signed-off-by: Marek Lindner --- net/batman-adv/routing.c | 61 ++++++++++++++++++++-------------------- net/batman-adv/types.h | 6 ++-- 2 files changed, 33 insertions(+), 34 deletions(-) diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 9185666ab3e0..29a689ac5693 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -155,7 +155,8 @@ static int is_bidirectional_neigh(struct orig_node *orig_node, struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL; struct hlist_node *node; unsigned char total_count; - int ret = 0; + uint8_t orig_eq_count, neigh_rq_count, tq_own; + int tq_asym_penalty, ret = 0; if (orig_node == orig_neigh_node) { rcu_read_lock(); @@ -216,23 +217,25 @@ static int is_bidirectional_neigh(struct orig_node *orig_node, orig_node->last_valid = jiffies; + spin_lock_bh(&orig_node->ogm_cnt_lock); + orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num]; + neigh_rq_count = neigh_node->real_packet_count; + spin_unlock_bh(&orig_node->ogm_cnt_lock); + /* pay attention to not get a value bigger than 100 % */ - total_count = (orig_neigh_node->bcast_own_sum[if_incoming->if_num] > - neigh_node->real_packet_count ? - neigh_node->real_packet_count : - orig_neigh_node->bcast_own_sum[if_incoming->if_num]); + total_count = (orig_eq_count > neigh_rq_count ? + neigh_rq_count : orig_eq_count); /* if we have too few packets (too less data) we set tq_own to zero */ /* if we receive too few packets it is not considered bidirectional */ if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) || - (neigh_node->real_packet_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM)) - orig_neigh_node->tq_own = 0; + (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM)) + tq_own = 0; else /* neigh_node->real_packet_count is never zero as we * only purge old information when getting new * information */ - orig_neigh_node->tq_own = (TQ_MAX_VALUE * total_count) / - neigh_node->real_packet_count; + tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count; /* * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does @@ -240,20 +243,16 @@ static int is_bidirectional_neigh(struct orig_node *orig_node, * punishes asymmetric links more. This will give a value * between 0 and TQ_MAX_VALUE */ - orig_neigh_node->tq_asym_penalty = - TQ_MAX_VALUE - - (TQ_MAX_VALUE * - (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) * - (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) * - (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count)) / - (TQ_LOCAL_WINDOW_SIZE * - TQ_LOCAL_WINDOW_SIZE * - TQ_LOCAL_WINDOW_SIZE); - - batman_packet->tq = ((batman_packet->tq * - orig_neigh_node->tq_own * - orig_neigh_node->tq_asym_penalty) / - (TQ_MAX_VALUE * TQ_MAX_VALUE)); + tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE * + (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) * + (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) * + (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) / + (TQ_LOCAL_WINDOW_SIZE * + TQ_LOCAL_WINDOW_SIZE * + TQ_LOCAL_WINDOW_SIZE); + + batman_packet->tq = ((batman_packet->tq * tq_own * tq_asym_penalty) / + (TQ_MAX_VALUE * TQ_MAX_VALUE)); bat_dbg(DBG_BATMAN, bat_priv, "bidirectional: " @@ -261,8 +260,7 @@ static int is_bidirectional_neigh(struct orig_node *orig_node, "real recv = %2i, local tq: %3i, asym_penalty: %3i, " "total tq: %3i\n", orig_node->orig, orig_neigh_node->orig, total_count, - neigh_node->real_packet_count, orig_neigh_node->tq_own, - orig_neigh_node->tq_asym_penalty, batman_packet->tq); + neigh_rq_count, tq_own, tq_asym_penalty, batman_packet->tq); /* if link has the minimum required transmission quality * consider it bidirectional */ @@ -559,18 +557,19 @@ static char count_real_packets(struct ethhdr *ethhdr, char is_duplicate = 0; int32_t seq_diff; int need_update = 0; - int set_mark; + int set_mark, ret = -1; orig_node = get_orig_node(bat_priv, batman_packet->orig); if (!orig_node) return 0; + spin_lock_bh(&orig_node->ogm_cnt_lock); seq_diff = batman_packet->seqno - orig_node->last_real_seqno; /* signalize caller that the packet is to be dropped. */ if (window_protected(bat_priv, seq_diff, &orig_node->batman_seqno_reset)) - goto err; + goto out; rcu_read_lock(); hlist_for_each_entry_rcu(tmp_neigh_node, node, @@ -603,12 +602,12 @@ static char count_real_packets(struct ethhdr *ethhdr, orig_node->last_real_seqno = batman_packet->seqno; } - kref_put(&orig_node->refcount, orig_node_free_ref); - return is_duplicate; + ret = is_duplicate; -err: +out: + spin_unlock_bh(&orig_node->ogm_cnt_lock); kref_put(&orig_node->refcount, orig_node_free_ref); - return -1; + return ret; } void receive_bat_packet(struct ethhdr *ethhdr, diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index e0140c65d8f3..9a142760bd9c 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -70,8 +70,6 @@ struct orig_node { struct neigh_node *router; unsigned long *bcast_own; uint8_t *bcast_own_sum; - uint8_t tq_own; - int tq_asym_penalty; unsigned long last_valid; unsigned long bcast_seqno_reset; unsigned long batman_seqno_reset; @@ -89,7 +87,9 @@ struct orig_node { struct kref refcount; struct bat_priv *bat_priv; unsigned long last_frag_packet; - spinlock_t ogm_cnt_lock; /* protects ogm counter */ + spinlock_t ogm_cnt_lock; /* protects: bcast_own, bcast_own_sum, + * neigh_node->real_bits, + * neigh_node->real_packet_count */ atomic_t bond_candidates; struct list_head bond_list; }; -- 2.34.1