| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1400576408-2290-1-git-send-email-pshelar@nicira.com>
Date: Tue, 20 May 2014 02:00:08 -0700
From: Pravin B Shelar <pshelar@...ira.com>
To: davem@...emloft.net
Cc: dev@...nvswitch.org, netdev@...r.kernel.org,
Jarno Rajahalme <jrajahalme@...ira.com>,
Pravin B Shelar <pshelar@...ira.com>
Subject: [PATCH net-next 04/13] openvswitch: Build flow cmd netlink reply only if needed.
From: Jarno Rajahalme <jrajahalme@...ira.com>
Use netlink_has_listeners() and NLM_F_ECHO flag to determine if a
reply is needed or not for OVS_FLOW_CMD_NEW, OVS_FLOW_CMD_SET, or
OVS_FLOW_CMD_DEL. Currently, OVS userspace does not request a reply
for OVS_FLOW_CMD_NEW, but usually does for OVS_FLOW_CMD_DEL, as stats
may have changed.
Signed-off-by: Jarno Rajahalme <jrajahalme@...ira.com>
Signed-off-by: Pravin B Shelar <pshelar@...ira.com>
---
net/openvswitch/datapath.c | 70 +++++++++++++++++++++++++++++++---------------
1 file changed, 48 insertions(+), 22 deletions(-)
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 138ea0c..cb5d64a 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -62,6 +62,15 @@
int ovs_net_id __read_mostly;
+/* Check if need to build a reply message.
+ * OVS userspace sets the NLM_F_ECHO flag if it needs the reply. */
+static bool ovs_must_notify(struct genl_info *info,
+ const struct genl_multicast_group *grp)
+{
+ return info->nlhdr->nlmsg_flags & NLM_F_ECHO ||
+ netlink_has_listeners(genl_info_net(info)->genl_sock, 0);
+}
+
static void ovs_notify(struct genl_family *family,
struct sk_buff *skb, struct genl_info *info)
{
@@ -746,27 +755,36 @@ error:
/* Must be called with ovs_mutex. */
static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow,
- struct genl_info *info)
+ struct genl_info *info,
+ bool always)
{
+ struct sk_buff *skb;
size_t len;
+ if (!always && !ovs_must_notify(info, &ovs_dp_flow_multicast_group))
+ return NULL;
+
len = ovs_flow_cmd_msg_size(ovsl_dereference(flow->sf_acts));
- return genlmsg_new_unicast(len, info, GFP_KERNEL);
+ skb = genlmsg_new_unicast(len, info, GFP_KERNEL);
+ if (!skb)
+ return ERR_PTR(-ENOMEM);
+
+ return skb;
}
/* Must be called with ovs_mutex. */
static struct sk_buff *ovs_flow_cmd_build_info(struct sw_flow *flow,
struct datapath *dp,
struct genl_info *info,
- u8 cmd)
+ u8 cmd, bool always)
{
struct sk_buff *skb;
int retval;
- skb = ovs_flow_cmd_alloc_info(flow, info);
- if (!skb)
- return ERR_PTR(-ENOMEM);
+ skb = ovs_flow_cmd_alloc_info(flow, info, always);
+ if (!skb || IS_ERR(skb))
+ return skb;
retval = ovs_flow_cmd_fill_info(flow, dp, skb, info->snd_portid,
info->snd_seq, 0, cmd);
@@ -850,7 +868,8 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
goto err_flow_free;
}
- reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
+ reply = ovs_flow_cmd_build_info(flow, dp, info,
+ OVS_FLOW_CMD_NEW, false);
} else {
/* We found a matching flow. */
/* Bail out if we're not allowed to modify an existing flow.
@@ -876,7 +895,8 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
rcu_assign_pointer(flow->sf_acts, acts);
ovs_nla_free_flow_actions(old_acts);
}
- reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
+ reply = ovs_flow_cmd_build_info(flow, dp, info,
+ OVS_FLOW_CMD_NEW, false);
/* Clear stats. */
if (a[OVS_FLOW_ATTR_CLEAR])
@@ -884,11 +904,14 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
}
ovs_unlock();
- if (!IS_ERR(reply))
- ovs_notify(&dp_flow_genl_family, reply, info);
- else
- genl_set_err(&dp_flow_genl_family, sock_net(skb->sk), 0,
- 0, PTR_ERR(reply));
+ if (reply) {
+ if (!IS_ERR(reply))
+ ovs_notify(&dp_flow_genl_family, reply, info);
+ else
+ genl_set_err(&dp_flow_genl_family, sock_net(skb->sk), 0,
+ 0, PTR_ERR(reply));
+ }
+
return 0;
err_flow_free:
@@ -935,7 +958,7 @@ static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
goto unlock;
}
- reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
+ reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW, true);
if (IS_ERR(reply)) {
err = PTR_ERR(reply);
goto unlock;
@@ -982,22 +1005,25 @@ static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
goto unlock;
}
- reply = ovs_flow_cmd_alloc_info(flow, info);
- if (!reply) {
- err = -ENOMEM;
+ reply = ovs_flow_cmd_alloc_info(flow, info, false);
+ if (IS_ERR(reply)) {
+ err = PTR_ERR(reply);
goto unlock;
}
ovs_flow_tbl_remove(&dp->table, flow);
- err = ovs_flow_cmd_fill_info(flow, dp, reply, info->snd_portid,
- info->snd_seq, 0, OVS_FLOW_CMD_DEL);
- BUG_ON(err < 0);
-
+ if (reply) {
+ err = ovs_flow_cmd_fill_info(flow, dp, reply, info->snd_portid,
+ info->snd_seq, 0,
+ OVS_FLOW_CMD_DEL);
+ BUG_ON(err < 0);
+ }
ovs_flow_free(flow, true);
ovs_unlock();
- ovs_notify(&dp_flow_genl_family, reply, info);
+ if (reply)
+ ovs_notify(&dp_flow_genl_family, reply, info);
return 0;
unlock:
ovs_unlock();
--
1.9.0
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists