Commit 1444c175 authored by Vlad Buslov's avatar Vlad Buslov Committed by David S. Miller
Browse files

net: sched: copy tunnel info when setting flow_action entry->tunnel 



In order to remove dependency on rtnl lock, modify tc_setup_flow_action()
to copy tunnel info, instead of just saving pointer to tunnel_key action
tunnel info. This is necessary to prevent concurrent action overwrite from
releasing tunnel info while it is being used by rtnl-unlocked driver.

Implement helper tcf_tunnel_info_copy() that is used to copy tunnel info
with all its options to dynamically allocated memory block. Modify
tc_cleanup_flow_action() to free dynamically allocated tunnel info.

Signed-off-by: default avatarVlad Buslov <vladbu@mellanox.com>
Acked-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5a6ff4b1

include/net/tc_act/tc_tunnel_key.h

+17 −0
Original line number Diff line number Diff line
@@ -59,4 +59,21 @@ static inline struct ip_tunnel_info *tcf_tunnel_info(const struct tc_action *a) 
	return NULL;

#endif

}



static inline struct ip_tunnel_info *

tcf_tunnel_info_copy(const struct tc_action *a)

{

#ifdef CONFIG_NET_CLS_ACT

	struct ip_tunnel_info *tun = tcf_tunnel_info(a);



	if (tun) {

		size_t tun_size = sizeof(*tun) + tun->options_len;

		struct ip_tunnel_info *tun_copy = kmemdup(tun, tun_size,

							  GFP_KERNEL);



		return tun_copy;

	}

#endif

	return NULL;

}

#endif /* __NET_TC_TUNNEL_KEY_H */

net/sched/cls_api.c

+8 −1
Original line number Diff line number Diff line
@@ -3279,6 +3279,9 @@ void tc_cleanup_flow_action(struct flow_action *flow_action) 
			if (entry->dev)

				dev_put(entry->dev);

			break;

		case FLOW_ACTION_TUNNEL_ENCAP:

			kfree(entry->tunnel);

			break;

		default:

			break;

		}
@@ -3355,7 +3358,11 @@ int tc_setup_flow_action(struct flow_action *flow_action, 
			}

		} else if (is_tcf_tunnel_set(act)) {

			entry->id = FLOW_ACTION_TUNNEL_ENCAP;

			entry->tunnel = tcf_tunnel_info(act);

			entry->tunnel = tcf_tunnel_info_copy(act);

			if (!entry->tunnel) {

				err = -ENOMEM;

				goto err_out;

			}

		} else if (is_tcf_tunnel_release(act)) {

			entry->id = FLOW_ACTION_TUNNEL_DECAP;

		} else if (is_tcf_pedit(act)) {