Upstream commit:
commit 9cc9a5cb176ccb4f2cda5ac34da5a659926f125f
Author: Tonghao Zhang <xiangxia.m....@gmail.com>
Date: Thu Jun 29 17:27:44 2017 -0700
datapath: Avoid using stack larger than 1024.
When compiling OvS-master on 4.4.0-81 kernel,
there is a warning:
CC [M] /root/ovs/datapath/linux/datapath.o
/root/ovs/datapath/linux/datapath.c: In function
'ovs_flow_cmd_set':
/root/ovs/datapath/linux/datapath.c:1221:1: warning:
the frame size of 1040 bytes is larger than 1024 bytes
[-Wframe-larger-than=]
This patch factors out match-init and action-copy to avoid
"Wframe-larger-than=1024" warning. Because mask is only
used to get actions, we new a function to save some
stack space.
Signed-off-by: Tonghao Zhang <xiangxia.m....@gmail.com>
Acked-by: Pravin B Shelar <pshe...@ovn.org>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Tonghao Zhang <xiangxia.m....@gmail.com>
---
datapath/datapath.c | 81 ++++++++++++++++++++++++++++++++++++++---------------
1 file changed, 58 insertions(+), 23 deletions(-)
diff --git a/datapath/datapath.c b/datapath/datapath.c
index c85029c..fb9f114 100644
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -1100,6 +1100,58 @@ static struct sw_flow_actions *get_flow_actions(struct
net *net,
return acts;
}
+/* Factor out match-init and action-copy to avoid
+ * "Wframe-larger-than=1024" warning. Because mask is only
+ * used to get actions, we new a function to save some
+ * stack space.
+ *
+ * If there are not key and action attrs, we return 0
+ * directly. In the case, the caller will also not use the
+ * match as before. If there is action attr, we try to get
+ * actions and save them to *acts. Before returning from
+ * the function, we reset the match->mask pointer. Because
+ * we should not to return match object with dangling reference
+ * to mask.
+ * */
+static int ovs_nla_init_match_and_action(struct net *net,
+ struct sw_flow_match *match,
+ struct sw_flow_key *key,
+ struct nlattr **a,
+ struct sw_flow_actions **acts,
+ bool log)
+{
+ struct sw_flow_mask mask;
+ int error = 0;
+
+ if (a[OVS_FLOW_ATTR_KEY]) {
+ ovs_match_init(match, key, true, &mask);
+ error = ovs_nla_get_match(net, match, a[OVS_FLOW_ATTR_KEY],
+ a[OVS_FLOW_ATTR_MASK], log);
+ if (error)
+ goto error;
+ }
+
+ if (a[OVS_FLOW_ATTR_ACTIONS]) {
+ if (!a[OVS_FLOW_ATTR_KEY]) {
+ OVS_NLERR(log,
+ "Flow key attribute not present in set
flow.");
+ return -EINVAL;
+ }
+
+ *acts = get_flow_actions(net, a[OVS_FLOW_ATTR_ACTIONS], key,
+ &mask, log);
+ if (IS_ERR(*acts)) {
+ error = PTR_ERR(*acts);
+ goto error;
+ }
+ }
+
+ /* On success, error is 0. */
+error:
+ match->mask = NULL;
+ return error;
+}
+
static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
{
struct net *net = sock_net(skb->sk);
@@ -1107,7 +1159,6 @@ static int ovs_flow_cmd_set(struct sk_buff *skb, struct
genl_info *info)
struct ovs_header *ovs_header = info->userhdr;
struct sw_flow_key key;
struct sw_flow *flow;
- struct sw_flow_mask mask;
struct sk_buff *reply = NULL;
struct datapath *dp;
struct sw_flow_actions *old_acts = NULL, *acts = NULL;
@@ -1119,34 +1170,18 @@ static int ovs_flow_cmd_set(struct sk_buff *skb, struct
genl_info *info)
bool ufid_present;
ufid_present = ovs_nla_get_ufid(&sfid, a[OVS_FLOW_ATTR_UFID], log);
- if (a[OVS_FLOW_ATTR_KEY]) {
- ovs_match_init(&match, &key, true, &mask);
- error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
- a[OVS_FLOW_ATTR_MASK], log);
- } else if (!ufid_present) {
+ if (!a[OVS_FLOW_ATTR_KEY] && !ufid_present) {
OVS_NLERR(log,
"Flow set message rejected, Key attribute missing.");
- error = -EINVAL;
+ return -EINVAL;
}
+
+ error = ovs_nla_init_match_and_action(net, &match, &key, a,
+ &acts, log);
if (error)
goto error;
- /* Validate actions. */
- if (a[OVS_FLOW_ATTR_ACTIONS]) {
- if (!a[OVS_FLOW_ATTR_KEY]) {
- OVS_NLERR(log,
- "Flow key attribute not present in set
flow.");
- error = -EINVAL;
- goto error;
- }
-
- acts = get_flow_actions(net, a[OVS_FLOW_ATTR_ACTIONS], &key,
- &mask, log);
- if (IS_ERR(acts)) {
- error = PTR_ERR(acts);
- goto error;
- }
-
+ if (acts) {
/* Can allocate before locking if have acts. */
reply = ovs_flow_cmd_alloc_info(acts, &sfid, info, false,
ufid_flags);
--
1.8.3.1
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