net: sched: lock action when translating it to flow_action infra
In order to remove dependency on rtnl lock, take action's tcfa_lock when
constructing its representation as flow_action_entry structure.
Refactor tcf_sample_get_group() to assume that caller holds tcf_lock and
don't take it manually. This callback is only called from flow_action infra
representation translator which now calls it with tcf_lock held, so this
refactoring is necessary to prevent deadlock.
Allocate memory with GFP_ATOMIC flag for ip_tunnel_info copy because
tcf_tunnel_info_copy() is only called from flow_action representation infra
code with tcf_lock spinlock taken.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index c2cdd0f..6105051 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -3435,7 +3435,7 @@ static void tcf_sample_get_group(struct flow_action_entry *entry,
int tc_setup_flow_action(struct flow_action *flow_action,
const struct tcf_exts *exts, bool rtnl_held)
{
- const struct tc_action *act;
+ struct tc_action *act;
int i, j, k, err = 0;
if (!exts)
@@ -3449,6 +3449,7 @@ int tc_setup_flow_action(struct flow_action *flow_action,
struct flow_action_entry *entry;
entry = &flow_action->entries[j];
+ spin_lock_bh(&act->tcfa_lock);
if (is_tcf_gact_ok(act)) {
entry->id = FLOW_ACTION_ACCEPT;
} else if (is_tcf_gact_shot(act)) {
@@ -3489,13 +3490,13 @@ int tc_setup_flow_action(struct flow_action *flow_action,
break;
default:
err = -EOPNOTSUPP;
- goto err_out;
+ goto err_out_locked;
}
} else if (is_tcf_tunnel_set(act)) {
entry->id = FLOW_ACTION_TUNNEL_ENCAP;
err = tcf_tunnel_encap_get_tunnel(entry, act);
if (err)
- goto err_out;
+ goto err_out_locked;
} else if (is_tcf_tunnel_release(act)) {
entry->id = FLOW_ACTION_TUNNEL_DECAP;
} else if (is_tcf_pedit(act)) {
@@ -3509,7 +3510,7 @@ int tc_setup_flow_action(struct flow_action *flow_action,
break;
default:
err = -EOPNOTSUPP;
- goto err_out;
+ goto err_out_locked;
}
entry->mangle.htype = tcf_pedit_htype(act, k);
entry->mangle.mask = tcf_pedit_mask(act, k);
@@ -3560,15 +3561,16 @@ int tc_setup_flow_action(struct flow_action *flow_action,
entry->mpls_mangle.ttl = tcf_mpls_ttl(act);
break;
default:
- goto err_out;
+ goto err_out_locked;
}
} else if (is_tcf_skbedit_ptype(act)) {
entry->id = FLOW_ACTION_PTYPE;
entry->ptype = tcf_skbedit_ptype(act);
} else {
err = -EOPNOTSUPP;
- goto err_out;
+ goto err_out_locked;
}
+ spin_unlock_bh(&act->tcfa_lock);
if (!is_tcf_pedit(act))
j++;
@@ -3582,6 +3584,9 @@ int tc_setup_flow_action(struct flow_action *flow_action,
tc_cleanup_flow_action(flow_action);
return err;
+err_out_locked:
+ spin_unlock_bh(&act->tcfa_lock);
+ goto err_out;
}
EXPORT_SYMBOL(tc_setup_flow_action);