mptcp: pm: Return local variable instead of freed pointer

JIRA: https://issues.redhat.com/browse/RHEL-115576
Upstream Status: net-next.git commit def9d09

commit def9d09
Author: Thorsten Blum <thorsten.blum@linux.dev>
Date:   Sun Apr 13 11:34:34 2025 +0200

    mptcp: pm: Return local variable instead of freed pointer

    Commit e4c28e3 ("mptcp: pm: move generic PM helpers to pm.c")
    removed an unnecessary if-check, which resulted in returning a freed
    pointer.

    This still works due to the implicit boolean conversion when returning
    the freed pointer from mptcp_remove_anno_list_by_saddr(), but it can be
    confusing and potentially error-prone. To improve clarity, add a local
    variable to explicitly return a boolean value instead.

    Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
    Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
    Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
    Link: https://patch.msgid.link/20250413-net-next-mptcp-sched-mib-sft-misc-v2-3-0f83a4350150@kernel.org
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Signed-off-by: Davide Caratti <dcaratti@redhat.com>

Author: dcaratti

net/mptcp/pm.c

@@ -146,10 +146,13 @@ bool mptcp_remove_anno_list_by_saddr(struct mptcp_sock *msk,
 				     const struct mptcp_addr_info *addr)
 {
 	struct mptcp_pm_add_entry *entry;
+	bool ret;
 
 	entry = mptcp_pm_del_add_timer(msk, addr, false);
+	ret = entry;
 	kfree(entry);
-	return entry;
+
+	return ret;
 }
 
 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk)