path: root/include/net/sch_generic.h
diff options
authorVlad Buslov <vladbu@mellanox.com>2019-02-11 10:55:38 +0200
committerDavid S. Miller <davem@davemloft.net>2019-02-12 13:41:32 -0500
commited76f5edccc98fa66f2337f0b3b255d6e1a568b7 (patch)
tree408b13681d6f13914e70783a7d345a560242a219 /include/net/sch_generic.h
parentnet: sched: protect chain template accesses with block lock (diff)
net: sched: protect filter_chain list with filter_chain_lock mutex
Extend tcf_chain with new filter_chain_lock mutex. Always lock the chain when accessing filter_chain list, instead of relying on rtnl lock. Dereference filter_chain with tcf_chain_dereference() lockdep macro to verify that all users of chain_list have the lock taken. Rearrange tp insert/remove code in tc_new_tfilter/tc_del_tfilter to execute all necessary code while holding chain lock in order to prevent invalidation of chain_info structure by potential concurrent change. This also serializes calls to tcf_chain0_head_change(), which allows head change callbacks to rely on filter_chain_lock for synchronization instead of rtnl mutex. Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Acked-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/sch_generic.h')
1 files changed, 17 insertions, 0 deletions
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 31b8ea66a47d..85993d7efee6 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -341,6 +341,8 @@ struct qdisc_skb_cb {
typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv);
struct tcf_chain {
+ /* Protects filter_chain. */
+ struct mutex filter_chain_lock;
struct tcf_proto __rcu *filter_chain;
struct list_head list;
struct tcf_block *block;
@@ -374,6 +376,21 @@ struct tcf_block {
struct rcu_head rcu;
+static inline bool lockdep_tcf_chain_is_locked(struct tcf_chain *chain)
+ return lockdep_is_held(&chain->filter_chain_lock);
+static inline bool lockdep_tcf_chain_is_locked(struct tcf_block *chain)
+ return true;
+#endif /* #ifdef CONFIG_PROVE_LOCKING */
+#define tcf_chain_dereference(p, chain) \
+ rcu_dereference_protected(p, lockdep_tcf_chain_is_locked(chain))
static inline void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
if (*flags & TCA_CLS_FLAGS_IN_HW)