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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,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 AA6FBC43381 for ; Mon, 1 Apr 2019 17:52:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 79E2920830 for ; Mon, 1 Apr 2019 17:52:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554141169; bh=SQdnGG2kIIjgpQLcM8gFqaAM4kojXkiOuzzGaJDzmrg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RSeYyQ5zG7XhrW2wYHu1CKaYyUGAS2aGd7HOZBxE81rPxwdeUbFnFawRxdDHGMTk4 EFNOAESmxvewIfDKEfVqOiMsXm3cVF71zY8EzRGVebKdQHbN9E4xG+pBwDwRw4KC7d inIIgtO7Q6oLVVu2dq5PnPLj9Wn7tquJvxW6jN2Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732284AbfDARwm (ORCPT ); Mon, 1 Apr 2019 13:52:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:58576 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732545AbfDAR01 (ORCPT ); Mon, 1 Apr 2019 13:26:27 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 10DA821852; Mon, 1 Apr 2019 17:26:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554139586; bh=SQdnGG2kIIjgpQLcM8gFqaAM4kojXkiOuzzGaJDzmrg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iVVYP4GtvPNl9meGIWSPKasQzhuv6ViBgam1qe25lmXLb7+I7gFS+OFpCQc9w7Off LP9M223iz4/Gy/a6coXTRnpLcJOxI9jVZFxg1139nkirJwegAMGk0noP2XxwiBeedm YDOsyH0g5tG2TNOhrfyH5CaEcGJCZwNLxsv994es= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Suanming.Mou" , Eric Dumazet , Stefano Brivio , Zhiqiang Liu , "David S. Miller" Subject: [PATCH 4.9 12/56] vxlan: Dont call gro_cells_destroy() before device is unregistered Date: Mon, 1 Apr 2019 19:02:28 +0200 Message-Id: <20190401170104.595904744@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401170103.398401360@linuxfoundation.org> References: <20190401170103.398401360@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zhiqiang Liu [ Upstream commit cc4807bb609230d8959fd732b0bf3bd4c2de8eac ] Commit ad6c9986bcb62 ("vxlan: Fix GRO cells race condition between receive and link delete") fixed a race condition for the typical case a vxlan device is dismantled from the current netns. But if a netns is dismantled, vxlan_destroy_tunnels() is called to schedule a unregister_netdevice_queue() of all the vxlan tunnels that are related to this netns. In vxlan_destroy_tunnels(), gro_cells_destroy() is called and finished before unregister_netdevice_queue(). This means that the gro_cells_destroy() call is done too soon, for the same reasons explained in above commit. So we need to fully respect the RCU rules, and thus must remove the gro_cells_destroy() call or risk use after-free. Fixes: 58ce31cca1ff ("vxlan: GRO support at tunnel layer") Signed-off-by: Suanming.Mou Suggested-by: Eric Dumazet Reviewed-by: Stefano Brivio Reviewed-by: Zhiqiang Liu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/vxlan.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -3375,10 +3375,8 @@ static void __net_exit vxlan_exit_net(st /* If vxlan->dev is in the same netns, it has already been added * to the list by the previous loop. */ - if (!net_eq(dev_net(vxlan->dev), net)) { - gro_cells_destroy(&vxlan->gro_cells); + if (!net_eq(dev_net(vxlan->dev), net)) unregister_netdevice_queue(vxlan->dev, &list); - } } unregister_netdevice_many(&list);