From patchwork Thu Mar 17 23:04:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishen Maloor X-Patchwork-Id: 12784645 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8108D4C64 for ; Thu, 17 Mar 2022 23:04:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1647558298; x=1679094298; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=/pBLACmcmwsc2zcau6Nts7S9fI0mNb4ija9uEq6QE2g=; b=E2V9/4/NBH5LPqa7ExApVsS5azSPJVG9uxocsWl6Wc5agZSuAqZ3HH1r MSBSVyqjF020oxUONPpMtCMVXkG0JyRmiRqZje6eC7oLagiRdGbddGy2i KtgDwowQ6kByzbVZjFkBtjLXfXOYjeUjdrlORFA4Z+3J21+kLoO8/V0Ay KS5lgQKl5wX28M7rOi/wC2ByZSA+Tmxkx7N/pDUtz/IrBA2H4dsOhQVL5 cFgtzv1yyaJvednrdM7qWQBGIV4xgBaLz4X0AXf1AmyG8nANwzNGOaOIo 914wT8Rc8i1QlNjyDGyj7L8sxJBE3wlQFR7gAKZ93OlHOJQTFsYzOwkrS g==; X-IronPort-AV: E=McAfee;i="6200,9189,10289"; a="257189950" X-IronPort-AV: E=Sophos;i="5.90,190,1643702400"; d="scan'208";a="257189950" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Mar 2022 16:04:56 -0700 X-IronPort-AV: E=Sophos;i="5.90,190,1643702400"; d="scan'208";a="499015054" Received: from otc-tsn-4.jf.intel.com ([10.23.153.135]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Mar 2022 16:04:55 -0700 From: Kishen Maloor To: kishen.maloor@intel.com, mptcp@lists.linux.dev Subject: [PATCH mptcp-next v8 2/6] mptcp: bypass in-kernel PM restrictions for non-kernel PMs Date: Thu, 17 Mar 2022 19:04:45 -0400 Message-Id: <20220317230449.763778-3-kishen.maloor@intel.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220317230449.763778-1-kishen.maloor@intel.com> References: <20220317230449.763778-1-kishen.maloor@intel.com> Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Current limits on the # of addresses/subflows must apply only to in-kernel PM managed sockets. Thus this change removes such restrictions on connections overseen by non-kernel (e.g. userspace) PMs. This change also ensures that the kernel does not record stats inside struct mptcp_pm_data updated along kernel code paths when exercised via non-kernel PMs. Additionally, address announcements are acknolwedged and subflow requests are honored only when it's deemed that a userspace path manager is active at the time. Signed-off-by: Kishen Maloor --- net/mptcp/pm.c | 15 +++++++++++++-- net/mptcp/pm_netlink.c | 10 ++++++++++ net/mptcp/protocol.h | 6 ++++++ net/mptcp/subflow.c | 4 +++- 4 files changed, 32 insertions(+), 3 deletions(-) diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index d0d31d5c198a..f9a12e6f4b4e 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -87,6 +87,9 @@ bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk) unsigned int subflows_max; int ret = 0; + if (mptcp_pm_is_userspace(msk)) + return mptcp_userspace_pm_active(msk); + subflows_max = mptcp_pm_get_subflows_max(msk); pr_debug("msk=%p subflows=%d max=%d allow=%d", msk, pm->subflows, @@ -179,7 +182,8 @@ void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, bool update_subflows; update_subflows = (ssk->sk_state == TCP_CLOSE) && - (subflow->request_join || subflow->mp_join); + (subflow->request_join || subflow->mp_join) && + mptcp_pm_is_kernel(msk); if (!READ_ONCE(pm->work_pending) && !update_subflows) return; @@ -208,7 +212,14 @@ void mptcp_pm_add_addr_received(struct mptcp_sock *msk, spin_lock_bh(&pm->lock); - if (!READ_ONCE(pm->accept_addr) || mptcp_pm_is_userspace(msk)) { + if (mptcp_pm_is_userspace(msk)) { + if (mptcp_userspace_pm_active(msk)) { + mptcp_pm_announce_addr(msk, addr, true); + mptcp_pm_add_addr_send_ack(msk); + } else { + __MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_ADDADDRDROP); + } + } else if (!READ_ONCE(pm->accept_addr)) { mptcp_pm_announce_addr(msk, addr, true); mptcp_pm_add_addr_send_ack(msk); } else if (mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_RECEIVED)) { diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index c1f4befb1e45..94d2bbb14eba 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -796,6 +796,9 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, if (!removed) continue; + if (!mptcp_pm_is_kernel(msk)) + continue; + if (rm_type == MPTCP_MIB_RMADDR) { msk->pm.add_addr_accepted--; WRITE_ONCE(msk->pm.accept_addr, true); @@ -1846,6 +1849,13 @@ static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gf nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); } +bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) +{ + return genl_has_listeners(&mptcp_genl_family, + sock_net((const struct sock *)msk), + MPTCP_PM_EV_GRP_OFFSET); +} + static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) { const struct inet_sock *issk = inet_sk(ssk); diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 3ef5bee66bcd..37ea34f9b599 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -781,6 +781,7 @@ void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp); void mptcp_event_addr_announced(const struct mptcp_sock *msk, const struct mptcp_addr_info *info); void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); +bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) { @@ -808,6 +809,11 @@ static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; } +static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) +{ + return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; +} + static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) { u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 30ffb00661bb..e10a1cc916d6 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -62,7 +62,9 @@ static void subflow_generate_hmac(u64 key1, u64 key2, u32 nonce1, u32 nonce2, static bool mptcp_can_accept_new_subflow(const struct mptcp_sock *msk) { return mptcp_is_fully_established((void *)msk) && - READ_ONCE(msk->pm.accept_subflow); + ((mptcp_pm_is_userspace(msk) && + mptcp_userspace_pm_active(msk)) || + READ_ONCE(msk->pm.accept_subflow)); } /* validate received token and create truncated hmac and nonce for SYN-ACK */