From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 4D50D1875 for ; Wed, 28 Dec 2022 15:54:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A069AC433EF; Wed, 28 Dec 2022 15:54:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672242884; bh=Qs8z/eMb9zZap8vuy7TCJ7fXrIA0nWBv7Nf/yamGJUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LuX/XJfwJipEEy7hsWdda/0mcQ9TsUt+2fTbwSB3xJRl7yDECIYMU+4Cp72uFKqxe 3tgpyYqQQK5WRl+ACoLW1TU712Sm5q3FMeM2pHicvVNC4LJsJIL3vCBSUBOuB6ww+f ozF6XmNQcu6roKUfDf3p+4nS7OtG2IT0ncJRVDFQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot , Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 5.15 657/731] ipv6/sit: use DEV_STATS_INC() to avoid data-races Date: Wed, 28 Dec 2022 15:42:44 +0100 Message-Id: <20221228144315.539101661@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144256.536395940@linuxfoundation.org> References: <20221228144256.536395940@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit cb34b7cf17ecf33499c9298943f85af247abc1e9 ] syzbot/KCSAN reported that multiple cpus are updating dev->stats.tx_error concurrently. This is because sit tunnels are NETIF_F_LLTX, meaning their ndo_start_xmit() is not protected by a spinlock. While original KCSAN report was about tx path, rx path has the same issue. Reported-by: syzbot Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv6/sit.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 946871741f12..d4cdc2b1b468 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -696,7 +696,7 @@ static int ipip6_rcv(struct sk_buff *skb) skb->dev = tunnel->dev; if (packet_is_spoofed(skb, iph, tunnel)) { - tunnel->dev->stats.rx_errors++; + DEV_STATS_INC(tunnel->dev, rx_errors); goto out; } @@ -716,8 +716,8 @@ static int ipip6_rcv(struct sk_buff *skb) net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", &iph->saddr, iph->tos); if (err > 1) { - ++tunnel->dev->stats.rx_frame_errors; - ++tunnel->dev->stats.rx_errors; + DEV_STATS_INC(tunnel->dev, rx_frame_errors); + DEV_STATS_INC(tunnel->dev, rx_errors); goto out; } } @@ -948,7 +948,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, if (!rt) { rt = ip_route_output_flow(tunnel->net, &fl4, NULL); if (IS_ERR(rt)) { - dev->stats.tx_carrier_errors++; + DEV_STATS_INC(dev, tx_carrier_errors); goto tx_error_icmp; } dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, fl4.saddr); @@ -956,14 +956,14 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, if (rt->rt_type != RTN_UNICAST) { ip_rt_put(rt); - dev->stats.tx_carrier_errors++; + DEV_STATS_INC(dev, tx_carrier_errors); goto tx_error_icmp; } tdev = rt->dst.dev; if (tdev == dev) { ip_rt_put(rt); - dev->stats.collisions++; + DEV_STATS_INC(dev, collisions); goto tx_error; } @@ -976,7 +976,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, mtu = dst_mtu(&rt->dst) - t_hlen; if (mtu < IPV4_MIN_MTU) { - dev->stats.collisions++; + DEV_STATS_INC(dev, collisions); ip_rt_put(rt); goto tx_error; } @@ -1015,7 +1015,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); if (!new_skb) { ip_rt_put(rt); - dev->stats.tx_dropped++; + DEV_STATS_INC(dev, tx_dropped); kfree_skb(skb); return NETDEV_TX_OK; } @@ -1045,7 +1045,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, dst_link_failure(skb); tx_error: kfree_skb(skb); - dev->stats.tx_errors++; + DEV_STATS_INC(dev, tx_errors); return NETDEV_TX_OK; } @@ -1064,7 +1064,7 @@ static netdev_tx_t sit_tunnel_xmit__(struct sk_buff *skb, return NETDEV_TX_OK; tx_error: kfree_skb(skb); - dev->stats.tx_errors++; + DEV_STATS_INC(dev, tx_errors); return NETDEV_TX_OK; } @@ -1093,7 +1093,7 @@ static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb, return NETDEV_TX_OK; tx_err: - dev->stats.tx_errors++; + DEV_STATS_INC(dev, tx_errors); kfree_skb(skb); return NETDEV_TX_OK; -- 2.35.1