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: f421436a59 ("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>
This commit is contained in:
Taehee Yoo 2020-03-13 06:50:24 +00:00 committed by David S. Miller
parent 173756b868
commit ca19c70f52

View File

@ -360,16 +360,14 @@ fail:
*/
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 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
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 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
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 @@ invalid:
return 0;
nla_put_failure:
kfree_skb(skb_out);
nlmsg_free(skb_out);
/* Fall through */
fail: