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| author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-11-30 04:08:58 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-12-09 08:55:59 -0800 |
| commit | 5eb027bb82d1f9d4af0df73a3ce08945ffc1b481 (patch) | |
| tree | 257a6a0a1990650cfc233af7e4368fa2d05f45b8 | |
| parent | e03d2dc771361ff27ca042b793fa34b27bd6f115 (diff) | |
sch_teql: fix lockdep splat
[ Upstream commit f7e57044eeb1841847c24aa06766c8290c202583 ]
We need rcu_read_lock() protection before using dst_get_neighbour(), and
we must cache its value (pass it to __teql_resolve())
teql_master_xmit() is called under rcu_read_lock_bh() protection, its
not enough.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | net/sched/sch_teql.c | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/net/sched/sch_teql.c b/net/sched/sch_teql.c index a3b7120fcc7..4f4c52c0eeb 100644 --- a/net/sched/sch_teql.c +++ b/net/sched/sch_teql.c @@ -225,11 +225,11 @@ static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt) static int -__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res, struct net_device *dev) +__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res, + struct net_device *dev, struct netdev_queue *txq, + struct neighbour *mn) { - struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, 0); - struct teql_sched_data *q = qdisc_priv(dev_queue->qdisc); - struct neighbour *mn = dst_get_neighbour(skb_dst(skb)); + struct teql_sched_data *q = qdisc_priv(txq->qdisc); struct neighbour *n = q->ncache; if (mn->tbl == NULL) @@ -262,17 +262,26 @@ __teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res, struct net_device * } static inline int teql_resolve(struct sk_buff *skb, - struct sk_buff *skb_res, struct net_device *dev) + struct sk_buff *skb_res, + struct net_device *dev, + struct netdev_queue *txq) { - struct netdev_queue *txq = netdev_get_tx_queue(dev, 0); + struct dst_entry *dst = skb_dst(skb); + struct neighbour *mn; + int res; + if (txq->qdisc == &noop_qdisc) return -ENODEV; - if (dev->header_ops == NULL || - skb_dst(skb) == NULL || - dst_get_neighbour(skb_dst(skb)) == NULL) + if (!dev->header_ops || !dst) return 0; - return __teql_resolve(skb, skb_res, dev); + + rcu_read_lock(); + mn = dst_get_neighbour(dst); + res = mn ? __teql_resolve(skb, skb_res, dev, txq, mn) : 0; + rcu_read_unlock(); + + return res; } static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev) @@ -307,7 +316,7 @@ restart: continue; } - switch (teql_resolve(skb, skb_res, slave)) { + switch (teql_resolve(skb, skb_res, slave, slave_txq)) { case 0: if (__netif_tx_trylock(slave_txq)) { unsigned int length = qdisc_pkt_len(skb); |