From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3704313-1519414471-2-6343606321055309237 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1519414470; b=J+SGeTFzaNY2U2LzVHN0SRyCaaR16iQp03AxarBB/ILJ0NR YoVXmlOQ+i1Zc+ayD9cLmDWbtAVY2sNWa/7GjzZpFlBGm+FBmnZt/zdzbfuSkKYE tAfJUEKZq7kJIM5zsHjXefIru/GcGgolAQ6Z+3WxoRap3hSu4oINOtR2WoO+BZtf +zYNJDR1Wyglf4ciyPRa005gGHAU9s3EhrrXBMVhlNmtoC1PFHU2+kBojcyWH1RD 9v86qZ7mLbmWtgkiNwGXaYyVRlXr9ugBUba9TOKA4CbqtUsTLPW9yX9ubKDGLfs+ G077QmYBLkmiFnAQVldR7pAYzv3NOrPcr27kl8A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1519414470; bh=jq314Kj8KOZsuwbluaoJjdfloS WHBRqHDu/Lz+6ECdU=; b=S22UNixedS49oLyb3ULZJomYq/qFIuh0MziGjxQOBt NrdCZN4oCljdHmoSfxseaO7l4E3pyuHl2CRmr2IHnv6mjmAxrRoMqM8S6PVk5TOF JCnN7sfa1QWUzpy01L+iOxmONNboJoP/uPOY6gy9zPFvb9Ny6xleFkCdAsjKEN6i YKGGNJ5y+RNXE3qSHn81Y0X//6wAKjfF6XKtqZQTnHib2wc/ibKK2KO5tVkuH2Rn AOBJYOiYCikXAev5wVbSgcxRR7FWrj1nl1e/eewONW0Mjs7RWAmG9RR8hVbt817T 78WjCI4UT7KcN8bUvbl74MqZbeq9z9IVHdt+MMlcxO5g== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934862AbeBWSvB (ORCPT ); Fri, 23 Feb 2018 13:51:01 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:45896 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934306AbeBWSu6 (ORCPT ); Fri, 23 Feb 2018 13:50:58 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot , Sowmini Varadhan , Santosh Shilimkar , "David S. Miller" Subject: [PATCH 4.14 042/159] rds: tcp: atomically purge entries from rds_tcp_conn_list during netns delete Date: Fri, 23 Feb 2018 19:25:50 +0100 Message-Id: <20180223170748.490604442@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180223170743.086611315@linuxfoundation.org> References: <20180223170743.086611315@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sowmini Varadhan commit f10b4cff98c6977668434fbf5dd58695eeca2897 upstream. The rds_tcp_kill_sock() function parses the rds_tcp_conn_list to find the rds_connection entries marked for deletion as part of the netns deletion under the protection of the rds_tcp_conn_lock. Since the rds_tcp_conn_list tracks rds_tcp_connections (which have a 1:1 mapping with rds_conn_path), multiple tc entries in the rds_tcp_conn_list will map to a single rds_connection, and will be deleted as part of the rds_conn_destroy() operation that is done outside the rds_tcp_conn_lock. The rds_tcp_conn_list traversal done under the protection of rds_tcp_conn_lock should not leave any doomed tc entries in the list after the rds_tcp_conn_lock is released, else another concurrently executiong netns delete (for a differnt netns) thread may trip on these entries. Reported-by: syzbot Signed-off-by: Sowmini Varadhan Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/rds/tcp.c | 9 +++++++-- net/rds/tcp.h | 1 + 2 files changed, 8 insertions(+), 2 deletions(-) --- a/net/rds/tcp.c +++ b/net/rds/tcp.c @@ -306,7 +306,8 @@ static void rds_tcp_conn_free(void *arg) rdsdebug("freeing tc %p\n", tc); spin_lock_irqsave(&rds_tcp_conn_lock, flags); - list_del(&tc->t_tcp_node); + if (!tc->t_tcp_node_detached) + list_del(&tc->t_tcp_node); spin_unlock_irqrestore(&rds_tcp_conn_lock, flags); kmem_cache_free(rds_tcp_conn_slab, tc); @@ -531,8 +532,12 @@ static void rds_tcp_kill_sock(struct net if (net != c_net || !tc->t_sock) continue; - if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn)) + if (!list_has_conn(&tmp_list, tc->t_cpath->cp_conn)) { list_move_tail(&tc->t_tcp_node, &tmp_list); + } else { + list_del(&tc->t_tcp_node); + tc->t_tcp_node_detached = true; + } } spin_unlock_irq(&rds_tcp_conn_lock); list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) { --- a/net/rds/tcp.h +++ b/net/rds/tcp.h @@ -12,6 +12,7 @@ struct rds_tcp_incoming { struct rds_tcp_connection { struct list_head t_tcp_node; + bool t_tcp_node_detached; struct rds_conn_path *t_cpath; /* t_conn_path_lock synchronizes the connection establishment between * rds_tcp_accept_one and rds_tcp_conn_path_connect