hsr: add restart routine into hsr_get_node_list()
The hsr_get_node_list() is to send node addresses to the userspace.
If there are so many nodes, it could fail because of buffer size.
In order to avoid this failure, the restart routine is added.
Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c
index d6760df..726bfe9 100644
--- a/net/hsr/hsr_netlink.c
+++ b/net/hsr/hsr_netlink.c
@@ -360,16 +360,14 @@
*/
static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
{
- /* For receiving */
- struct nlattr *na;
- struct net_device *hsr_dev;
-
- /* For sending */
- struct sk_buff *skb_out;
- void *msg_head;
- struct hsr_priv *hsr;
- void *pos;
unsigned char addr[ETH_ALEN];
+ struct net_device *hsr_dev;
+ struct sk_buff *skb_out;
+ struct hsr_priv *hsr;
+ bool restart = false;
+ struct nlattr *na;
+ void *pos = NULL;
+ void *msg_head;
int res;
if (!info)
@@ -387,8 +385,9 @@
if (!is_hsr_master(hsr_dev))
goto rcu_unlock;
+restart:
/* Send reply */
- skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+ skb_out = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_ATOMIC);
if (!skb_out) {
res = -ENOMEM;
goto fail;
@@ -402,17 +401,28 @@
goto nla_put_failure;
}
- res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex);
- if (res < 0)
- goto nla_put_failure;
+ if (!restart) {
+ res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex);
+ if (res < 0)
+ goto nla_put_failure;
+ }
hsr = netdev_priv(hsr_dev);
- pos = hsr_get_next_node(hsr, NULL, addr);
+ if (!pos)
+ pos = hsr_get_next_node(hsr, NULL, addr);
while (pos) {
res = nla_put(skb_out, HSR_A_NODE_ADDR, ETH_ALEN, addr);
- if (res < 0)
+ if (res < 0) {
+ if (res == -EMSGSIZE) {
+ genlmsg_end(skb_out, msg_head);
+ genlmsg_unicast(genl_info_net(info), skb_out,
+ info->snd_portid);
+ restart = true;
+ goto restart;
+ }
goto nla_put_failure;
+ }
pos = hsr_get_next_node(hsr, pos, addr);
}
rcu_read_unlock();
@@ -429,7 +439,7 @@
return 0;
nla_put_failure:
- kfree_skb(skb_out);
+ nlmsg_free(skb_out);
/* Fall through */
fail:
