From patchwork Sun Jun 6 20:05:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aleksander Jan Bajkowski X-Patchwork-Id: 12302263 X-Patchwork-Delegate: kuba@kernel.org 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 A72F4C4743D for ; Sun, 6 Jun 2021 20:06:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8714661156 for ; Sun, 6 Jun 2021 20:06:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230081AbhFFUIc (ORCPT ); Sun, 6 Jun 2021 16:08:32 -0400 Received: from mx3.wp.pl ([212.77.101.10]:42238 "EHLO mx3.wp.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229723AbhFFUIa (ORCPT ); Sun, 6 Jun 2021 16:08:30 -0400 Received: (wp-smtpd smtp.wp.pl 19935 invoked from network); 6 Jun 2021 22:06:38 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wp.pl; s=1024a; t=1623009998; bh=hQhPaaBVb++b0UTU9Rraa6ZhDCCVr/iAER3n3txOb2w=; h=From:To:Cc:Subject; b=bc32+VPrlLz28hAoAr/gDwfWa4O+1iRtdkAtsLo9EyCqbQcEiNlE4wvHNC2SbCtdy hFFRhn14TlwEdgw3uKokTspXfJiVr3laIEunnvCcpbBpJ7Y8Uch6dZpWjKWCj1byBl czWq7tJsJ/7ZK7CFT2W6H/pPGoSXJ7udqmJV5Dwc= Received: from riviera.nat.ds.pw.edu.pl (HELO LAPTOP-OLEK.lan) (olek2@wp.pl@[194.29.137.1]) (envelope-sender ) by smtp.wp.pl (WP-SMTPD) with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP for ; 6 Jun 2021 22:06:38 +0200 From: Aleksander Jan Bajkowski To: hauke@hauke-m.de, davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Aleksander Jan Bajkowski Subject: [PATCH net] lantiq: net: fix duplicated skb in rx descriptor ring Date: Sun, 6 Jun 2021 22:05:51 +0200 Message-Id: <20210606200551.1609521-1-olek2@wp.pl> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-WP-DKIM-Status: good (id: wp.pl) X-WP-MailID: 8a3beb05101d63dc280b56f4a59e28da X-WP-AV: skaner antywirusowy Poczty Wirtualnej Polski X-WP-SPAM: NO 0000000 [QYOk] Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The previous commit didn't fix the bug properly. By mistake, it replaces the pointer of the next skb in the descriptor ring instead of the current one. As a result, the two descriptors are assigned the same SKB. The error is seen during the iperf test when skb_put tries to insert a second packet and exceeds the available buffer. Fixes: c7718ee96dbc ("net: lantiq: fix memory corruption in RX ring ") Signed-off-by: Aleksander Jan Bajkowski --- drivers/net/ethernet/lantiq_xrx200.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index 36dc3e5f6218..e710f83b3700 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -193,17 +193,18 @@ static int xrx200_hw_receive(struct xrx200_chan *ch) int ret; ret = xrx200_alloc_skb(ch); - - ch->dma.desc++; - ch->dma.desc %= LTQ_DESC_NUM; - if (ret) { ch->skb[ch->dma.desc] = skb; net_dev->stats.rx_dropped++; + ch->dma.desc++; + ch->dma.desc %= LTQ_DESC_NUM; netdev_err(net_dev, "failed to allocate new rx buffer\n"); return ret; } + ch->dma.desc++; + ch->dma.desc %= LTQ_DESC_NUM; + skb_put(skb, len); skb->protocol = eth_type_trans(skb, net_dev); netif_receive_skb(skb);