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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B08CFC4360F for ; Thu, 4 Apr 2019 12:45:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 75490206B7 for ; Thu, 4 Apr 2019 12:45:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="F9mckCSK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729194AbfDDMpj (ORCPT ); Thu, 4 Apr 2019 08:45:39 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:40142 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729279AbfDDMpj (ORCPT ); Thu, 4 Apr 2019 08:45:39 -0400 Received: by mail-pg1-f196.google.com with SMTP id u9so1191716pgo.7 for ; Thu, 04 Apr 2019 05:45:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=E15nqD0zgawgmCxkvj8E4iZUQ77y20cNhhtnDaI4VFQ=; b=F9mckCSKbroYCsp8/VDbMOYXBKsFICOsvoYGOYIE7YXaMTIOwkJOUka8JzOAYtPIqv 7/ZtyjIiTocEhpBLCdnXIyo/mFSl0xJSnN1B3Dt5hWZk0jFYmAR+ZO2Fd0ZhN11cFp7u aDbRWPuFb8Py/w3ObHH2ZvoLsflhCbGdR8hZ1I/V6dKW3oM9uOOSa70vQ/C52bDrrCvo xqCIMHhncLTGZ6Ejx0hOVW/zqcfq8Wp69VFgaMe3jsfWEeZWUOyIhXPnqdS2r5ilF3XL h9EzMqTn2GkXZjR17yzGj5tLascHz6WwWZkkCrqEwB6jD0SY+//SGdFZxUo/mnotA+sK 1QcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=E15nqD0zgawgmCxkvj8E4iZUQ77y20cNhhtnDaI4VFQ=; b=OwJuP/ixXwn/NEeG1uwlpu1TIwl1xdCZ9Bo7E6WtczrMxdnqPpm503xQWwtYx8OwJs koQ6QhW5yuMMYTHROORpxm8PrDWWsdjLNUDBXLmL2kJVCgAZrnhh5kENBc0vBjsdaKhv DUEQ7uO/s97qxANVSefIfAf0S5tMdhFTc2Gd8e8b7NOED+S3Y3vhG5XABhujXH8AmglK KXMMsZkMRq9igCshOL7B8+3W1x0GftQ97xSqYanCM41p82eru/SAEA+Q/o80+LPR8g/E IV0doXMRaPvFiYUypoc26Gb2oZ/7B+c5yz4RGiQZxojgwcwG1SfSlMf5O1qcsWgIXYKn U3Qg== X-Gm-Message-State: APjAAAWyZEa5uS3AcRxZ/FiKp5txa0NXY3A010OY4zeFD6RQQT3ZqbIh QCMZIkZasqh3GRR/6fReER+dIKG+MMM= X-Google-Smtp-Source: APXvYqwsx0v2svIuZIc1TWiosxWrXiOcNrkwuMrtPNWvQH8/DPx3leIrkUsqs3A7iE1xZM0Js/pjHA== X-Received: by 2002:aa7:8b12:: with SMTP id f18mr5709258pfd.89.1554381937452; Thu, 04 Apr 2019 05:45:37 -0700 (PDT) Received: from dhcp-12-139.nay.redhat.com ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id i31sm36652323pgi.36.2019.04.04.05.45.34 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 04 Apr 2019 05:45:36 -0700 (PDT) From: Hangbin Liu To: netdev@vger.kernel.org Cc: Wang Chen , David Miller , Stefano Brivio , Hangbin Liu Subject: [PATCH net] netdevice: Fix promiscuity and allmulti negative overflow Date: Thu, 4 Apr 2019 20:45:18 +0800 Message-Id: <20190404124518.16794-1-liuhangbin@gmail.com> X-Mailer: git-send-email 2.19.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Similarly to dad9b335c694 ("netdevice: Fix promiscuity and allmulti overflow"), we should not decrease promiscuity if it is already 0. An example is after adding a team interface to bridge, the team interface will enter promisc mode. Then if we add a slave to team0, the slave will keep promisc off. If we remove team from bridge, both team0 and slave will decrease the promiscuity, which will cause a negative overflow on the slave. The team's issue will be fixed in a separate patch. Reviewed-by: Stefano Brivio Signed-off-by: Hangbin Liu --- net/core/dev.c | 54 ++++++++++++++++++++++---------------------------- 1 file changed, 24 insertions(+), 30 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 2b67f2aa59dd..9744e9f696ba 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7338,22 +7338,19 @@ static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) ASSERT_RTNL(); - dev->flags |= IFF_PROMISC; - dev->promiscuity += inc; - if (dev->promiscuity == 0) { - /* - * Avoid overflow. - * If inc causes overflow, untouch promisc and return error. - */ - if (inc < 0) - dev->flags &= ~IFF_PROMISC; - else { - dev->promiscuity -= inc; - pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n", - dev->name); - return -EOVERFLOW; - } + if ((inc < 0 && dev->promiscuity + inc > dev->promiscuity) || + (inc > 0 && dev->promiscuity + inc < dev->promiscuity)) { + pr_warn("%s: increase promiscuity %u by %d failed, promiscuity feature of device might be broken.\n", + dev->name, dev->promiscuity, inc); + return -EOVERFLOW; } + + dev->promiscuity += inc; + if (dev->promiscuity) + dev->flags |= IFF_PROMISC; + else + dev->flags &= ~IFF_PROMISC; + if (dev->flags != old_flags) { pr_info("device %s %s promiscuous mode\n", dev->name, @@ -7409,22 +7406,19 @@ static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) ASSERT_RTNL(); - dev->flags |= IFF_ALLMULTI; - dev->allmulti += inc; - if (dev->allmulti == 0) { - /* - * Avoid overflow. - * If inc causes overflow, untouch allmulti and return error. - */ - if (inc < 0) - dev->flags &= ~IFF_ALLMULTI; - else { - dev->allmulti -= inc; - pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n", - dev->name); - return -EOVERFLOW; - } + if ((inc < 0 && dev->allmulti + inc > dev->allmulti) || + (inc > 0 && dev->allmulti + inc < dev->allmulti)) { + pr_warn("%s: increase allmulti %u by %d failed, allmulti feature of device might be broken.\n", + dev->name, dev->allmulti, inc); + return -EOVERFLOW; } + + dev->allmulti += inc; + if (dev->allmulti) + dev->flags |= IFF_ALLMULTI; + else + dev->flags &= ~IFF_ALLMULTI; + if (dev->flags ^ old_flags) { dev_change_rx_flags(dev, IFF_ALLMULTI); dev_set_rx_mode(dev); -- 2.19.2