From e0266319413d5d687ba7b6df7ca99e4b9724a4f2 Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Tue, 12 Nov 2024 20:18:33 +0100 Subject: [PATCH 1/3] mptcp: update local address flags when setting it Just like in-kernel pm, when userspace pm does set_flags, it needs to send out MP_PRIO signal, and also modify the flags of the corresponding address entry in the local address list. This patch implements the missing logic. Traverse all address entries on userspace_pm_local_addr_list to find the local address entry, if bkup is true, set the flags of this entry with FLAG_BACKUP, otherwise, clear FLAG_BACKUP. Fixes: 892f396c8e68 ("mptcp: netlink: issue MP_PRIO signals from userspace PMs") Cc: stable@vger.kernel.org Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20241112-net-mptcp-misc-6-12-pm-v1-1-b835580cefa8@kernel.org Signed-off-by: Jakub Kicinski --- net/mptcp/pm_userspace.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c index 56dfea9862b7..3f888bfe1462 100644 --- a/net/mptcp/pm_userspace.c +++ b/net/mptcp/pm_userspace.c @@ -560,6 +560,7 @@ int mptcp_userspace_pm_set_flags(struct sk_buff *skb, struct genl_info *info) 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; @@ -601,6 +602,17 @@ int mptcp_userspace_pm_set_flags(struct sk_buff *skb, struct genl_info *info) if (loc.flags & MPTCP_PM_ADDR_FLAG_BACKUP) bkup = 1; + spin_lock_bh(&msk->pm.lock); + list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { + if (mptcp_addresses_equal(&entry->addr, &loc.addr, false)) { + if (bkup) + entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP; + else + entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP; + } + } + spin_unlock_bh(&msk->pm.lock); + lock_sock(sk); ret = mptcp_pm_nl_mp_prio_send_ack(msk, &loc.addr, &rem.addr, bkup); release_sock(sk); From f642c5c4d528d11bd78b6c6f84f541cd3c0bea86 Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Tue, 12 Nov 2024 20:18:34 +0100 Subject: [PATCH 2/3] mptcp: hold pm lock when deleting entry When traversing userspace_pm_local_addr_list and deleting an entry from it in mptcp_pm_nl_remove_doit(), msk->pm.lock should be held. This patch holds this lock before mptcp_userspace_pm_lookup_addr_by_id() and releases it after list_move() in mptcp_pm_nl_remove_doit(). Fixes: d9a4594edabf ("mptcp: netlink: Add MPTCP_PM_CMD_REMOVE") Cc: stable@vger.kernel.org Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20241112-net-mptcp-misc-6-12-pm-v1-2-b835580cefa8@kernel.org Signed-off-by: Jakub Kicinski --- net/mptcp/pm_userspace.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c index 3f888bfe1462..e35178f5205f 100644 --- a/net/mptcp/pm_userspace.c +++ b/net/mptcp/pm_userspace.c @@ -308,14 +308,17 @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info) lock_sock(sk); + spin_lock_bh(&msk->pm.lock); match = mptcp_userspace_pm_lookup_addr_by_id(msk, id_val); if (!match) { GENL_SET_ERR_MSG(info, "address with specified id not found"); + spin_unlock_bh(&msk->pm.lock); release_sock(sk); goto out; } list_move(&match->list, &free_list); + spin_unlock_bh(&msk->pm.lock); mptcp_pm_remove_addrs(msk, &free_list); From db3eab8110bc0520416101b6a5b52f44a43fb4cf Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" Date: Tue, 12 Nov 2024 20:18:35 +0100 Subject: [PATCH 3/3] mptcp: pm: use _rcu variant under rcu_read_lock In mptcp_pm_create_subflow_or_signal_addr(), rcu_read_(un)lock() are used as expected to iterate over the list of local addresses, but list_for_each_entry() was used instead of list_for_each_entry_rcu() in __lookup_addr(). It is important to use this variant which adds the required READ_ONCE() (and diagnostic checks if enabled). Because __lookup_addr() is also used in mptcp_pm_nl_set_flags() where it is called under the pernet->lock and not rcu_read_lock(), an extra condition is then passed to help the diagnostic checks making sure either the associated spin lock or the RCU lock is held. Fixes: 86e39e04482b ("mptcp: keep track of local endpoint still available for each msk") Cc: stable@vger.kernel.org Reviewed-by: Geliang Tang Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20241112-net-mptcp-misc-6-12-pm-v1-3-b835580cefa8@kernel.org Signed-off-by: Jakub Kicinski --- net/mptcp/pm_netlink.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index db586a5b3866..45a2b5f05d38 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -524,7 +524,8 @@ __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info) { struct mptcp_pm_addr_entry *entry; - list_for_each_entry(entry, &pernet->local_addr_list, list) { + list_for_each_entry_rcu(entry, &pernet->local_addr_list, list, + lockdep_is_held(&pernet->lock)) { if (mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) return entry; }