From patchwork Fri Jan 21 00:35:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mat Martineau X-Patchwork-Id: 12719189 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B537C433EF for ; Fri, 21 Jan 2022 00:35:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378422AbiAUAfi (ORCPT ); Thu, 20 Jan 2022 19:35:38 -0500 Received: from mga17.intel.com ([192.55.52.151]:65249 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378419AbiAUAfh (ORCPT ); Thu, 20 Jan 2022 19:35:37 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1642725337; x=1674261337; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0BGbOTx/lurssaXCoUHuwmVPIkh6j2wbdvVsR1sRXc0=; b=CBRdvi/AfzJN1HgdkrEZw4Ro/VvGBGCTh0oMor6x9LFxwHaX4Fdh1A8p 437U+E1Wakk+w+6bMpiRb94x5Z1uGT2t3brLg5oVaOZgbT+s9pljmupW1 JNW3DfY9cY6cGJalFK+s9Ix1t+TtljXM2h0bADSNwIbiNnKQXwTO3TRvf 0G75LM6M+QHGnITMCFRKCMMZN3n00TOhJKV+SBeU9E9UXK0YGduT16AEE ShoUkrkcHCmHvLmLrQQ5EXDjw7w1092zuyu/7UJco73EC3m2xh7nDoJe8 cQqtZ8FteM0EiStrl8PXFfzocbNi89209E/uW07s/ZALJ3CdT1ovMSwuF w==; X-IronPort-AV: E=McAfee;i="6200,9189,10233"; a="226200818" X-IronPort-AV: E=Sophos;i="5.88,303,1635231600"; d="scan'208";a="226200818" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jan 2022 16:35:37 -0800 X-IronPort-AV: E=Sophos;i="5.88,303,1635231600"; d="scan'208";a="531215215" Received: from mjmartin-desk2.amr.corp.intel.com (HELO mjmartin-desk2.intel.com) ([10.212.220.167]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Jan 2022 16:35:37 -0800 From: Mat Martineau To: netdev@vger.kernel.org Cc: Paolo Abeni , davem@davemloft.net, kuba@kernel.org, matthieu.baerts@tessares.net, geliang.tang@suse.com, mptcp@lists.linux.dev, Mat Martineau Subject: [PATCH net 1/3] mptcp: fix msk traversal in mptcp_nl_cmd_set_flags() Date: Thu, 20 Jan 2022 16:35:27 -0800 Message-Id: <20220121003529.54930-2-mathew.j.martineau@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220121003529.54930-1-mathew.j.martineau@linux.intel.com> References: <20220121003529.54930-1-mathew.j.martineau@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Paolo Abeni The MPTCP endpoint list is under RCU protection, guarded by the pernet spinlock. mptcp_nl_cmd_set_flags() traverses the list without acquiring the spin-lock nor under the RCU critical section. This change addresses the issue performing the lookup and the endpoint update under the pernet spinlock. Fixes: 0f9f696a502e ("mptcp: add set_flags command in PM netlink") Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau --- net/mptcp/pm_netlink.c | 37 +++++++++++++++++++++++++++---------- 1 file changed, 27 insertions(+), 10 deletions(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 75af1f701e1d..f17a09f7fbf9 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -478,6 +478,20 @@ __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) return NULL; } +static struct mptcp_pm_addr_entry * +__lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info, + bool lookup_by_id) +{ + struct mptcp_pm_addr_entry *entry; + + list_for_each_entry(entry, &pernet->local_addr_list, list) { + if ((!lookup_by_id && addresses_equal(&entry->addr, info, true)) || + (lookup_by_id && entry->addr.id == info->id)) + return entry; + } + return NULL; +} + static int lookup_id_by_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *addr) { @@ -1763,18 +1777,21 @@ static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info) return -EOPNOTSUPP; } - list_for_each_entry(entry, &pernet->local_addr_list, list) { - if ((!lookup_by_id && addresses_equal(&entry->addr, &addr.addr, true)) || - (lookup_by_id && entry->addr.id == addr.addr.id)) { - mptcp_nl_addr_backup(net, &entry->addr, bkup); - - if (bkup) - entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP; - else - entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP; - } + spin_lock_bh(&pernet->lock); + entry = __lookup_addr(pernet, &addr.addr, lookup_by_id); + if (!entry) { + spin_unlock_bh(&pernet->lock); + return -EINVAL; } + if (bkup) + entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP; + else + entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP; + addr = *entry; + spin_unlock_bh(&pernet->lock); + + mptcp_nl_addr_backup(net, &addr.addr, bkup); return 0; }