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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 0F1D5C4332D for ; Wed, 18 Mar 2020 21:06:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD3B320409 for ; Wed, 18 Mar 2020 21:06:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584565584; bh=jNGLwEqLEg/bq/n3ga/hFjU9k5nHiKPvDv1e07tAKiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NgV1yDTtadSiQlmhg6uUcAYVZtRJ4C35P3z0r5bhck7VrFSCRk7PG0STyXjMDLJjO 93p/9sSsORYwDJpfmW7ZVHGOEzjkZgcxRoTi4cBXb2FPFg8qrb1MIf2m/1yWz4Pbt4 Xb2RrSvS0N18KY5nRjc3Y20WK96Nl3ONbY38RprQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727909AbgCRUyi (ORCPT ); Wed, 18 Mar 2020 16:54:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:54250 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727884AbgCRUyg (ORCPT ); Wed, 18 Mar 2020 16:54:36 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B52442098B; Wed, 18 Mar 2020 20:54:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584564875; bh=jNGLwEqLEg/bq/n3ga/hFjU9k5nHiKPvDv1e07tAKiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wTCJyagWmOnn+FqVCfQXGOlSKY8mNip8pCdeIr8vWH//pvwSpF4gggUxNryEBtcln 48A79nbUgse/ksfo5q31OW4kb9vhCopgJ3rxTSGH7+QlKRFz9AUUAbn8jevVa34aw2 pSuzELz7ULKbMLlpnwfYvEKo6Pv6pfrM4A6fOcxY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mahesh Bandewar , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 46/73] macvlan: add cond_resched() during multicast processing Date: Wed, 18 Mar 2020 16:53:10 -0400 Message-Id: <20200318205337.16279-46-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200318205337.16279-1-sashal@kernel.org> References: <20200318205337.16279-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Mahesh Bandewar [ Upstream commit ce9a4186f9ac475c415ffd20348176a4ea366670 ] The Rx bound multicast packets are deferred to a workqueue and macvlan can also suffer from the same attack that was discovered by Syzbot for IPvlan. This solution is not as effective as in IPvlan. IPvlan defers all (Tx and Rx) multicast packet processing to a workqueue while macvlan does this way only for the Rx. This fix should address the Rx codition to certain extent. Tx is still suseptible. Tx multicast processing happens when .ndo_start_xmit is called, hence we cannot add cond_resched(). However, it's not that severe since the user which is generating / flooding will be affected the most. Fixes: 412ca1550cbe ("macvlan: Move broadcasts into a work queue") Signed-off-by: Mahesh Bandewar Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/macvlan.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index c5bf61565726b..26f6be4796c75 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -334,6 +334,8 @@ static void macvlan_process_broadcast(struct work_struct *w) if (src) dev_put(src->dev); consume_skb(skb); + + cond_resched(); } } -- 2.20.1