From: Vlad Buslov <vladbu@mellanox.com>
Date: Mon, 26 Aug 2019 16:45:05 +0300
Subject: net: sched: copy tunnel info when setting flow_action entry->tunnel
Patch-mainline: v5.4-rc1
Git-commit: 1444c175a37443d3f6d3db825df050741452c3c3
References: bsc#1154353
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: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/net/tc_act/tc_tunnel_key.h | 17 +++++++++++++++++
net/sched/cls_api.c | 9 ++++++++-
2 files changed, 25 insertions(+), 1 deletion(-)
--- a/include/net/tc_act/tc_tunnel_key.h
+++ b/include/net/tc_act/tc_tunnel_key.h
@@ -59,4 +59,21 @@ static inline struct ip_tunnel_info *tcf
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 */
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -3279,6 +3279,9 @@ void tc_cleanup_flow_action(struct flow_
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_act
}
} 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)) {