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=-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,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 1FAD5C433ED for ; Thu, 20 May 2021 18:41:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E8BFC6135C for ; Thu, 20 May 2021 18:41:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235656AbhETSml (ORCPT ); Thu, 20 May 2021 14:42:41 -0400 Received: from mx4.wp.pl ([212.77.101.12]:31689 "EHLO mx4.wp.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232681AbhETSmk (ORCPT ); Thu, 20 May 2021 14:42:40 -0400 Received: (wp-smtpd smtp.wp.pl 17612 invoked from network); 20 May 2021 20:41:11 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wp.pl; s=1024a; t=1621536071; bh=fY5+omcrJznCtWB0A7TnS3SUznVJFzPnJ8BdRvY4bI4=; h=From:To:Cc:Subject; b=FiQb62MERkmGuBpgdlk+wBtKomPT2ou75/JX9K9CIAfpaT0NYv0/fGX+yz5/I1XlU i9qRCHnYhKsyfQRimdAYHotHWILMdxv8eIN9zwfii7UFo7+UT/oxdovRUUZao9fJJN f7i6bgxPhvu50PYea+M6PJktrFCRjBFnQAUAyn24= 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 ; 20 May 2021 20:41:11 +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] net: lantiq: fix memory corruption in RX ring Date: Thu, 20 May 2021 20:40:54 +0200 Message-Id: <20210520184054.38477-1-olek2@wp.pl> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-WP-DKIM-Status: good (id: wp.pl) X-WP-MailID: 41c3d39c9522285ac9aafd1fc8d36e5f X-WP-AV: skaner antywirusowy Poczty Wirtualnej Polski X-WP-SPAM: NO 0000000 [IUP0] Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In a situation where memory allocation or dma mapping fails, an invalid address is programmed into the descriptor. This can lead to memory corruption. If the memory allocation fails, DMA should reuse the previous skb and mapping and drop the packet. This patch also increments rx drop counter. Signed-off-by: Aleksander Jan Bajkowski --- drivers/net/ethernet/lantiq_xrx200.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index 41c2ad210bc9..36dc3e5f6218 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -154,6 +154,7 @@ static int xrx200_close(struct net_device *net_dev) static int xrx200_alloc_skb(struct xrx200_chan *ch) { + dma_addr_t mapping; int ret = 0; ch->skb[ch->dma.desc] = netdev_alloc_skb_ip_align(ch->priv->net_dev, @@ -163,16 +164,17 @@ static int xrx200_alloc_skb(struct xrx200_chan *ch) goto skip; } - ch->dma.desc_base[ch->dma.desc].addr = dma_map_single(ch->priv->dev, - ch->skb[ch->dma.desc]->data, XRX200_DMA_DATA_LEN, - DMA_FROM_DEVICE); - if (unlikely(dma_mapping_error(ch->priv->dev, - ch->dma.desc_base[ch->dma.desc].addr))) { + mapping = dma_map_single(ch->priv->dev, ch->skb[ch->dma.desc]->data, + XRX200_DMA_DATA_LEN, DMA_FROM_DEVICE); + if (unlikely(dma_mapping_error(ch->priv->dev, mapping))) { dev_kfree_skb_any(ch->skb[ch->dma.desc]); ret = -ENOMEM; goto skip; } + ch->dma.desc_base[ch->dma.desc].addr = mapping; + /* Make sure the address is written before we give it to HW */ + wmb(); skip: ch->dma.desc_base[ch->dma.desc].ctl = LTQ_DMA_OWN | LTQ_DMA_RX_OFFSET(NET_IP_ALIGN) | @@ -196,6 +198,8 @@ static int xrx200_hw_receive(struct xrx200_chan *ch) ch->dma.desc %= LTQ_DESC_NUM; if (ret) { + ch->skb[ch->dma.desc] = skb; + net_dev->stats.rx_dropped++; netdev_err(net_dev, "failed to allocate new rx buffer\n"); return ret; } -- 2.30.2