mptcp: add needs_id for netlink appending addr

Just the same as userspace PM, a new parameter needs_id is added for
in-kernel PM mptcp_pm_nl_append_new_local_addr() too.

Add a new helper mptcp_pm_has_addr_attr_id() to check whether an address
ID is set from PM or not.

In mptcp_pm_nl_get_local_id(), needs_id is always true, but in
mptcp_pm_nl_add_addr_doit(), pass mptcp_pm_has_addr_attr_id() to
needs_it.

Fixes: efd5a4c04e18 ("mptcp: add the address ID assignment bitmap")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 287a60381eae6e39c68d49a65530ea5bdc8a6675..a24c9128dee9e72336280edf3cfbe3f1bca1136c 100644 (file)
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -901,7 +901,8 @@ static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry)
 }
 
 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
-                                            struct mptcp_pm_addr_entry *entry)
+                                            struct mptcp_pm_addr_entry *entry,
+                                            bool needs_id)
 {
        struct mptcp_pm_addr_entry *cur, *del_entry = NULL;
        unsigned int addr_max;
@@ -949,7 +950,7 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
                }
        }
 
-       if (!entry->addr.id) {
+       if (!entry->addr.id && needs_id) {
 find_next:
                entry->addr.id = find_next_zero_bit(pernet->id_bitmap,
                                                    MPTCP_PM_MAX_ADDR_ID + 1,
@@ -960,7 +961,7 @@ find_next:
                }
        }
 
-       if (!entry->addr.id)
+       if (!entry->addr.id && needs_id)
                goto out;
 
        __set_bit(entry->addr.id, pernet->id_bitmap);
@@ -1092,7 +1093,7 @@ int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc
        entry->ifindex = 0;
        entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
        entry->lsk = NULL;
-       ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
+       ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true);
        if (ret < 0)
                kfree(entry);
 
@@ -1285,6 +1286,18 @@ next:
        return 0;
 }
 
+static bool mptcp_pm_has_addr_attr_id(const struct nlattr *attr,
+                                     struct genl_info *info)
+{
+       struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1];
+
+       if (!nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr,
+                                        mptcp_pm_address_nl_policy, info->extack) &&
+           tb[MPTCP_PM_ADDR_ATTR_ID])
+               return true;
+       return false;
+}
+
 int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info)
 {
        struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
@@ -1326,7 +1339,8 @@ int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info)
                        goto out_free;
                }
        }
-       ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
+       ret = mptcp_pm_nl_append_new_local_addr(pernet, entry,
+                                               !mptcp_pm_has_addr_attr_id(attr, info));
        if (ret < 0) {
                GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret);
                goto out_free;