From mboxrd@z Thu Jan 1 00:00:00 1970 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 A8949E95A96 for ; Mon, 9 Oct 2023 13:13:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376947AbjJINNO (ORCPT ); Mon, 9 Oct 2023 09:13:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376943AbjJINNB (ORCPT ); Mon, 9 Oct 2023 09:13:01 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA1B310F2 for ; Mon, 9 Oct 2023 06:11:59 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 021E8C43391; Mon, 9 Oct 2023 13:11:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696857119; bh=TeTV9nkuaN906CaqNvWreNtgtfVz6qU3ihuNVr/LhwY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LVQ1hjsAGWjf5Z5I3CYiHVwqMF6HnfX6b+LqbfkW04heQ+w7l8mdtrKWXFxhM7eNz A/WpfxnzyyRiGU0kR3SoiYQVnlptJIyIC3Net3xFkWzfHsVJiIwG3nlEZL08ayB8O3 J92u5qF0TuRzomzl6/VMYtkIiTSyPYqUDHtrsq/U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , David Ahern , "David S. Miller" , Sasha Levin Subject: [PATCH 6.5 103/163] neighbour: fix data-races around n->output Date: Mon, 9 Oct 2023 15:01:07 +0200 Message-ID: <20231009130126.873256885@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231009130124.021290599@linuxfoundation.org> References: <20231009130124.021290599@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 5baa0433a15eadd729625004c37463acb982eca7 ] n->output field can be read locklessly, while a writer might change the pointer concurrently. Add missing annotations to prevent load-store tearing. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/net/neighbour.h | 2 +- net/bridge/br_netfilter_hooks.c | 2 +- net/core/neighbour.c | 10 +++++----- 3 files changed, 7 insertions(+), 7 deletions(-) diff --git a/include/net/neighbour.h b/include/net/neighbour.h index f6a8ecc6b1fa7..ccc4a0f8b4ad8 100644 --- a/include/net/neighbour.h +++ b/include/net/neighbour.h @@ -541,7 +541,7 @@ static inline int neigh_output(struct neighbour *n, struct sk_buff *skb, READ_ONCE(hh->hh_len)) return neigh_hh_output(hh, skb); - return n->output(n, skb); + return READ_ONCE(n->output)(n, skb); } static inline struct neighbour * diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c index 1a801fab9543e..0be889905c2b6 100644 --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -294,7 +294,7 @@ int br_nf_pre_routing_finish_bridge(struct net *net, struct sock *sk, struct sk_ /* tell br_dev_xmit to continue with forwarding */ nf_bridge->bridged_dnat = 1; /* FIXME Need to refragment */ - ret = neigh->output(neigh, skb); + ret = READ_ONCE(neigh->output)(neigh, skb); } neigh_release(neigh); return ret; diff --git a/net/core/neighbour.c b/net/core/neighbour.c index b57d3ea3ccc9e..f16ec0e8a0348 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -410,7 +410,7 @@ static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev, */ __skb_queue_purge(&n->arp_queue); n->arp_queue_len_bytes = 0; - n->output = neigh_blackhole; + WRITE_ONCE(n->output, neigh_blackhole); if (n->nud_state & NUD_VALID) n->nud_state = NUD_NOARP; else @@ -920,7 +920,7 @@ static void neigh_suspect(struct neighbour *neigh) { neigh_dbg(2, "neigh %p is suspected\n", neigh); - neigh->output = neigh->ops->output; + WRITE_ONCE(neigh->output, neigh->ops->output); } /* Neighbour state is OK; @@ -932,7 +932,7 @@ static void neigh_connect(struct neighbour *neigh) { neigh_dbg(2, "neigh %p is connected\n", neigh); - neigh->output = neigh->ops->connected_output; + WRITE_ONCE(neigh->output, neigh->ops->connected_output); } static void neigh_periodic_work(struct work_struct *work) @@ -1449,7 +1449,7 @@ static int __neigh_update(struct neighbour *neigh, const u8 *lladdr, if (n2) n1 = n2; } - n1->output(n1, skb); + READ_ONCE(n1->output)(n1, skb); if (n2) neigh_release(n2); rcu_read_unlock(); @@ -3155,7 +3155,7 @@ int neigh_xmit(int index, struct net_device *dev, rcu_read_unlock(); goto out_kfree_skb; } - err = neigh->output(neigh, skb); + err = READ_ONCE(neigh->output)(neigh, skb); rcu_read_unlock(); } else if (index == NEIGH_LINK_TABLE) { -- 2.40.1