mptcp: add mptcp_userspace_pm_get_sock helper

Each userspace pm netlink function uses nla_get_u32() to get the msk
token value, then pass it to mptcp_token_get_sock() to get the msk.
Finally check whether userspace PM is selected on this msk. It makes
sense to wrap them into a helper, named mptcp_userspace_pm_get_sock(),
to do this.

This patch doesn't change the behaviour of the code, just refactoring.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20241213-net-next-mptcp-pm-misc-cleanup-v1-3-ddb6d00109a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index 6a27fab238f15b577e1e17225d4450e60ffd25d7..afb04343e74d2340cd77e298489b55340dda0899 100644 (file)
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -173,36 +173,50 @@ bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk,
        return backup;
 }
 
-int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info)
+static struct mptcp_sock *mptcp_userspace_pm_get_sock(const struct genl_info *info)
 {
        struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
+       struct mptcp_sock *msk;
+
+       if (!token) {
+               GENL_SET_ERR_MSG(info, "missing required token");
+               return NULL;
+       }
+
+       msk = mptcp_token_get_sock(genl_info_net(info), nla_get_u32(token));
+       if (!msk) {
+               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+               return NULL;
+       }
+
+       if (!mptcp_pm_is_userspace(msk)) {
+               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
+               sock_put((struct sock *)msk);
+               return NULL;
+       }
+
+       return msk;
+}
+
+int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info)
+{
        struct nlattr *addr = info->attrs[MPTCP_PM_ATTR_ADDR];
        struct mptcp_pm_addr_entry addr_val;
        struct mptcp_sock *msk;
        int err = -EINVAL;
        struct sock *sk;
-       u32 token_val;
 
-       if (!addr || !token) {
-               GENL_SET_ERR_MSG(info, "missing required inputs");
+       if (!addr) {
+               GENL_SET_ERR_MSG(info, "missing required address");
                return err;
        }
 
-       token_val = nla_get_u32(token);
-
-       msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
-       if (!msk) {
-               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+       msk = mptcp_userspace_pm_get_sock(info);
+       if (!msk)
                return err;
-       }
 
        sk = (struct sock *)msk;
 
-       if (!mptcp_pm_is_userspace(msk)) {
-               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
-               goto announce_err;
-       }
-
        err = mptcp_pm_parse_entry(addr, info, true, &addr_val);
        if (err < 0) {
                GENL_SET_ERR_MSG(info, "error parsing local address");
@@ -275,7 +289,6 @@ remove_err:
 
 int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
 {
-       struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
        struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID];
        struct mptcp_pm_addr_entry *match;
        struct mptcp_pm_addr_entry *entry;
@@ -283,30 +296,21 @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
        LIST_HEAD(free_list);
        int err = -EINVAL;
        struct sock *sk;
-       u32 token_val;
        u8 id_val;
 
-       if (!id || !token) {
-               GENL_SET_ERR_MSG(info, "missing required inputs");
+       if (!id) {
+               GENL_SET_ERR_MSG(info, "missing required ID");
                return err;
        }
 
        id_val = nla_get_u8(id);
-       token_val = nla_get_u32(token);
 
-       msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
-       if (!msk) {
-               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+       msk = mptcp_userspace_pm_get_sock(info);
+       if (!msk)
                return err;
-       }
 
        sk = (struct sock *)msk;
 
-       if (!mptcp_pm_is_userspace(msk)) {
-               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
-               goto out;
-       }
-
        if (id_val == 0) {
                err = mptcp_userspace_pm_remove_id_zero_address(msk, info);
                goto out;
@@ -343,7 +347,6 @@ out:
 int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info)
 {
        struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
-       struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
        struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
        struct mptcp_pm_addr_entry entry = { 0 };
        struct mptcp_addr_info addr_r;
@@ -351,28 +354,18 @@ int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info)
        struct mptcp_sock *msk;
        int err = -EINVAL;
        struct sock *sk;
-       u32 token_val;
 
-       if (!laddr || !raddr || !token) {
-               GENL_SET_ERR_MSG(info, "missing required inputs");
+       if (!laddr || !raddr) {
+               GENL_SET_ERR_MSG(info, "missing required address(es)");
                return err;
        }
 
-       token_val = nla_get_u32(token);
-
-       msk = mptcp_token_get_sock(genl_info_net(info), token_val);
-       if (!msk) {
-               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+       msk = mptcp_userspace_pm_get_sock(info);
+       if (!msk)
                return err;
-       }
 
        sk = (struct sock *)msk;
 
-       if (!mptcp_pm_is_userspace(msk)) {
-               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
-               goto create_err;
-       }
-
        err = mptcp_pm_parse_entry(laddr, info, true, &entry);
        if (err < 0) {
                NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
@@ -475,35 +468,24 @@ static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk,
 int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info)
 {
        struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
-       struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
        struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
        struct mptcp_addr_info addr_l;
        struct mptcp_addr_info addr_r;
        struct mptcp_sock *msk;
        struct sock *sk, *ssk;
        int err = -EINVAL;
-       u32 token_val;
 
-       if (!laddr || !raddr || !token) {
-               GENL_SET_ERR_MSG(info, "missing required inputs");
+       if (!laddr || !raddr) {
+               GENL_SET_ERR_MSG(info, "missing required address(es)");
                return err;
        }
 
-       token_val = nla_get_u32(token);
-
-       msk = mptcp_token_get_sock(genl_info_net(info), token_val);
-       if (!msk) {
-               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+       msk = mptcp_userspace_pm_get_sock(info);
+       if (!msk)
                return err;
-       }
 
        sk = (struct sock *)msk;
 
-       if (!mptcp_pm_is_userspace(msk)) {
-               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
-               goto destroy_err;
-       }
-
        err = mptcp_pm_parse_addr(laddr, info, &addr_l);
        if (err < 0) {
                NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
@@ -566,31 +548,19 @@ int mptcp_userspace_pm_set_flags(struct sk_buff *skb, struct genl_info *info)
        struct mptcp_pm_addr_entry loc = { .addr = { .family = AF_UNSPEC }, };
        struct mptcp_pm_addr_entry rem = { .addr = { .family = AF_UNSPEC }, };
        struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
-       struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
        struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
-       struct net *net = sock_net(skb->sk);
        struct mptcp_pm_addr_entry *entry;
        struct mptcp_sock *msk;
        int ret = -EINVAL;
        struct sock *sk;
-       u32 token_val;
        u8 bkup = 0;
 
-       token_val = nla_get_u32(token);
-
-       msk = mptcp_token_get_sock(net, token_val);
-       if (!msk) {
-               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+       msk = mptcp_userspace_pm_get_sock(info);
+       if (!msk)
                return ret;
-       }
 
        sk = (struct sock *)msk;
 
-       if (!mptcp_pm_is_userspace(msk)) {
-               GENL_SET_ERR_MSG(info, "userspace PM not selected");
-               goto set_flags_err;
-       }
-
        ret = mptcp_pm_parse_entry(attr, info, false, &loc);
        if (ret < 0)
                goto set_flags_err;
@@ -637,30 +607,20 @@ int mptcp_userspace_pm_dump_addr(struct sk_buff *msg,
                DECLARE_BITMAP(map, MPTCP_PM_MAX_ADDR_ID + 1);
        } *bitmap;
        const struct genl_info *info = genl_info_dump(cb);
-       struct net *net = sock_net(msg->sk);
        struct mptcp_pm_addr_entry *entry;
        struct mptcp_sock *msk;
-       struct nlattr *token;
        int ret = -EINVAL;
        struct sock *sk;
        void *hdr;
 
        bitmap = (struct id_bitmap *)cb->ctx;
-       token = info->attrs[MPTCP_PM_ATTR_TOKEN];
 
-       msk = mptcp_token_get_sock(net, nla_get_u32(token));
-       if (!msk) {
-               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+       msk = mptcp_userspace_pm_get_sock(info);
+       if (!msk)
                return ret;
-       }
 
        sk = (struct sock *)msk;
 
-       if (!mptcp_pm_is_userspace(msk)) {
-               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
-               goto out;
-       }
-
        lock_sock(sk);
        spin_lock_bh(&msk->pm.lock);
        mptcp_for_each_userspace_pm_addr(msk, entry) {
@@ -685,7 +645,6 @@ int mptcp_userspace_pm_dump_addr(struct sk_buff *msg,
        release_sock(sk);
        ret = msg->len;
 
-out:
        sock_put(sk);
        return ret;
 }
@@ -694,28 +653,19 @@ int mptcp_userspace_pm_get_addr(struct sk_buff *skb,
                                struct genl_info *info)
 {
        struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
-       struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
        struct mptcp_pm_addr_entry addr, *entry;
-       struct net *net = sock_net(skb->sk);
        struct mptcp_sock *msk;
        struct sk_buff *msg;
        int ret = -EINVAL;
        struct sock *sk;
        void *reply;
 
-       msk = mptcp_token_get_sock(net, nla_get_u32(token));
-       if (!msk) {
-               NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
+       msk = mptcp_userspace_pm_get_sock(info);
+       if (!msk)
                return ret;
-       }
 
        sk = (struct sock *)msk;
 
-       if (!mptcp_pm_is_userspace(msk)) {
-               GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
-               goto out;
-       }
-
        ret = mptcp_pm_parse_entry(attr, info, false, &addr);
        if (ret < 0)
                goto out;