mptcp: pm: avoid calling PM specific code from core

When destroying an MPTCP socket, some userspace PM specific code was
called from mptcp_destroy_common() in protocol.c. That feels wrong, and
it is the only case.

Instead, the core now calls mptcp_pm_destroy() from pm.c which is now in
charge of cleaning the announced addresses list, and ask the different
PMs to do extra cleaning if needed, e.g. the userspace PM, if used, will
clean the local addresses list.

While at it, the userspace PM specific helper has been prefixed with
'mptcp_userspace_pm_' like the other ones.

No behavioural changes intended.

Signed-off-by: Matthieu Baerts (NGI0) <[email protected]>

Author: matttbe

net/mptcp/pm.c

@@ -599,6 +599,14 @@ bool mptcp_pm_addr_families_match(const struct sock *sk,
 #endif
 }
 
+void mptcp_pm_destroy(struct mptcp_sock *msk)
+{
+	mptcp_pm_free_anno_list(msk);
+
+	if (mptcp_pm_is_userspace(msk))
+		mptcp_userspace_pm_free_local_addr_list(msk);
+}
+
 void mptcp_pm_data_reset(struct mptcp_sock *msk)
 {
 	u8 pm_type = mptcp_get_pm_type(sock_net((struct sock *)msk));

net/mptcp/pm_userspace.c

@@ -12,15 +12,12 @@
 	list_for_each_entry(__entry,						\
 			    &((__msk)->pm.userspace_pm_local_addr_list), list)
 
-void mptcp_free_local_addr_list(struct mptcp_sock *msk)
+void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk)
 {
 	struct mptcp_pm_addr_entry *entry, *tmp;
 	struct sock *sk = (struct sock *)msk;
 	LIST_HEAD(free_list);
 
-	if (!mptcp_pm_is_userspace(msk))
-		return;
-
 	spin_lock_bh(&msk->pm.lock);
 	list_splice_init(&msk->pm.userspace_pm_local_addr_list, &free_list);
 	spin_unlock_bh(&msk->pm.lock);

net/mptcp/protocol.c

@@ -3305,8 +3305,7 @@ void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags)
 	 * inet_sock_destruct() will dispose it
 	 */
 	mptcp_token_destroy(msk);
-	mptcp_pm_free_anno_list(msk);
-	mptcp_free_local_addr_list(msk);
+	mptcp_pm_destroy(msk);
 }
 
 static void mptcp_destroy(struct sock *sk)

net/mptcp/protocol.h

@@ -988,6 +988,7 @@ __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum su
 void __init mptcp_pm_init(void);
 void mptcp_pm_data_init(struct mptcp_sock *msk);
 void mptcp_pm_data_reset(struct mptcp_sock *msk);
+void mptcp_pm_destroy(struct mptcp_sock *msk);
 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
 			struct mptcp_addr_info *addr);
 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info,
@@ -1047,7 +1048,7 @@ int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_
 void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
 				struct mptcp_pm_addr_entry *entry);
 
-void mptcp_free_local_addr_list(struct mptcp_sock *msk);
+void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk);
 
 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
 		 const struct sock *ssk, gfp_t gfp);