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    Subject[PATCH 3.2 027/140] batman-adv: Fix lock for ogm cnt access in batadv_iv_ogm_calc_tq
    3.2.100-rc1 review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Sven Eckelmann <sven@narfation.org>

    commit 5ba7dcfe77037b67016263ea597a8b431692ecab upstream.

    The originator node object orig_neigh_node is used to when accessing the
    bcast_own(_sum) and real_packet_count information. The access to them has
    to be protected with the spinlock in orig_neigh_node.

    But the function uses the lock in orig_node instead. This is incorrect
    because they could be two different originator node objects.

    Fixes: 0ede9f41b217 ("batman-adv: protect bit operations to count OGMs with spinlock")
    Signed-off-by: Sven Eckelmann <sven@narfation.org>
    Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
    [bwh: Backported to 3.2:
    - s/bat_iv\.ogm_cnt_lock/ogm_cnt_lock/
    - Adjust context]
    Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
    ---
    net/batman-adv/bat_iv_ogm.c | 4 ++--
    1 file changed, 2 insertions(+), 2 deletions(-)

    --- a/net/batman-adv/bat_iv_ogm.c
    +++ b/net/batman-adv/bat_iv_ogm.c
    @@ -760,10 +760,10 @@ static int bat_ogm_calc_tq(struct orig_n
    orig_node->last_valid = jiffies;

    /* find packet count of corresponding one hop neighbor */
    - spin_lock_bh(&orig_node->ogm_cnt_lock);
    + spin_lock_bh(&orig_neigh_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);
    + spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);

    /* pay attention to not get a value bigger than 100 % */
    total_count = (orig_eq_count > neigh_rq_count ?
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