datapath: Check maximum netlink message size

In kernels < 4.9 the maximum netlink message size is 16KB.

See http://www.spinics.net/lists/netdev/msg431592.html

Signed-off-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

diff --git a/datapath/flow_netlink.c b/datapath/flow_netlink.c
index df9d88ee5b8b4ac689b747dc188495805dd654f1..b3b209269dcc8e563b8d6fa19261f6c93c615083 100644 (file)
--- a/datapath/flow_netlink.c
+++ b/datapath/flow_netlink.c
@@ -1902,7 +1902,11 @@ int ovs_nla_put_mask(const struct sw_flow *flow, struct sk_buff *skb)
                                OVS_FLOW_ATTR_MASK, true, skb);
 }
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4,9,0)
+#define MAX_ACTIONS_BUFSIZE    (16 * 1024)
+#else
 #define MAX_ACTIONS_BUFSIZE    (32 * 1024)
+#endif
 
 static struct sw_flow_actions *nla_alloc_flow_actions(int size, bool log)
 {