hsr: use rcu_read_lock() in hsr_get_node_{list/status}()

hsr_get_node_{list/status}() are not under rtnl_lock() because
they are callback functions of generic netlink.
But they use __dev_get_by_index() without rtnl_lock().
So, it would use unsafe data.
In order to fix it, rcu_read_lock() and dev_get_by_index_rcu()
are used instead of __dev_get_by_index().

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 06:50:14 +00:00 committed by David S. Miller
parent dcadaec224
commit 173756b868
2 changed files with 23 additions and 25 deletions

View File

@ -482,12 +482,9 @@ int hsr_get_node_data(struct hsr_priv *hsr,
struct hsr_port *port;
unsigned long tdiff;
rcu_read_lock();
node = find_node_by_addr_A(&hsr->node_db, addr);
if (!node) {
rcu_read_unlock();
return -ENOENT; /* No such entry */
}
if (!node)
return -ENOENT;
ether_addr_copy(addr_b, node->macaddress_B);
@ -522,7 +519,5 @@ int hsr_get_node_data(struct hsr_priv *hsr,
*addr_b_ifindex = -1;
}
rcu_read_unlock();
return 0;
}

View File

@ -251,15 +251,16 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
if (!na)
goto invalid;
hsr_dev = __dev_get_by_index(genl_info_net(info),
nla_get_u32(info->attrs[HSR_A_IFINDEX]));
rcu_read_lock();
hsr_dev = dev_get_by_index_rcu(genl_info_net(info),
nla_get_u32(info->attrs[HSR_A_IFINDEX]));
if (!hsr_dev)
goto invalid;
goto rcu_unlock;
if (!is_hsr_master(hsr_dev))
goto invalid;
goto rcu_unlock;
/* Send reply */
skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
if (!skb_out) {
res = -ENOMEM;
goto fail;
@ -313,12 +314,10 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
res = nla_put_u16(skb_out, HSR_A_IF1_SEQ, hsr_node_if1_seq);
if (res < 0)
goto nla_put_failure;
rcu_read_lock();
port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
if (port)
res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX,
port->dev->ifindex);
rcu_read_unlock();
if (res < 0)
goto nla_put_failure;
@ -328,20 +327,22 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
res = nla_put_u16(skb_out, HSR_A_IF2_SEQ, hsr_node_if2_seq);
if (res < 0)
goto nla_put_failure;
rcu_read_lock();
port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
if (port)
res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX,
port->dev->ifindex);
rcu_read_unlock();
if (res < 0)
goto nla_put_failure;
rcu_read_unlock();
genlmsg_end(skb_out, msg_head);
genlmsg_unicast(genl_info_net(info), skb_out, info->snd_portid);
return 0;
rcu_unlock:
rcu_read_unlock();
invalid:
netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
return 0;
@ -351,6 +352,7 @@ nla_put_failure:
/* Fall through */
fail:
rcu_read_unlock();
return res;
}
@ -377,15 +379,16 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
if (!na)
goto invalid;
hsr_dev = __dev_get_by_index(genl_info_net(info),
nla_get_u32(info->attrs[HSR_A_IFINDEX]));
rcu_read_lock();
hsr_dev = dev_get_by_index_rcu(genl_info_net(info),
nla_get_u32(info->attrs[HSR_A_IFINDEX]));
if (!hsr_dev)
goto invalid;
goto rcu_unlock;
if (!is_hsr_master(hsr_dev))
goto invalid;
goto rcu_unlock;
/* Send reply */
skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
if (!skb_out) {
res = -ENOMEM;
goto fail;
@ -405,14 +408,11 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
hsr = netdev_priv(hsr_dev);
rcu_read_lock();
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) {
rcu_read_unlock();
if (res < 0)
goto nla_put_failure;
}
pos = hsr_get_next_node(hsr, pos, addr);
}
rcu_read_unlock();
@ -422,6 +422,8 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
return 0;
rcu_unlock:
rcu_read_unlock();
invalid:
netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
return 0;
@ -431,6 +433,7 @@ nla_put_failure:
/* Fall through */
fail:
rcu_read_unlock();
return res;
}