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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 D96A8C6377B for ; Thu, 15 Jul 2021 19:12:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8DDB613E6 for ; Thu, 15 Jul 2021 19:12:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244484AbhGOTOv (ORCPT ); Thu, 15 Jul 2021 15:14:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:34984 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240997AbhGOS6t (ORCPT ); Thu, 15 Jul 2021 14:58:49 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A2ADA613D4; Thu, 15 Jul 2021 18:55:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626375343; bh=X0bu4H7WOFKLkbG4+PvRP5lJ23vKTpaLCOAkkv0fX30=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zK2w+NLRL88ER8JupN/fp18vOgW2SZ583ZoNr8nLA75qngFiGPZ9FeRBYdG/7uMKa 1W+9eeUlqnXzMAo9sdpBDwBwv7+U1VCH53akz1oHISLqlzwJfoAimdKDtF7JIOKnQe kz7mynOcJ1DlA+Fx9SOTBKHOLE3q8xuSbfY84RKU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xie Yongji , Jason Wang , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.12 046/242] virtio-net: Add validation for used length Date: Thu, 15 Jul 2021 20:36:48 +0200 Message-Id: <20210715182600.275545240@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210715182551.731989182@linuxfoundation.org> References: <20210715182551.731989182@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xie Yongji [ Upstream commit ad993a95c508417acdeb15244109e009e50d8758 ] This adds validation for used length (might come from an untrusted device) to avoid data corruption or loss. Signed-off-by: Xie Yongji Acked-by: Jason Wang Link: https://lore.kernel.org/r/20210531135852.113-1-xieyongji@bytedance.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/virtio_net.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 0824e6999e49..447582fa20a5 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -660,6 +660,12 @@ static struct sk_buff *receive_small(struct net_device *dev, len -= vi->hdr_len; stats->bytes += len; + if (unlikely(len > GOOD_PACKET_LEN)) { + pr_debug("%s: rx error: len %u exceeds max size %d\n", + dev->name, len, GOOD_PACKET_LEN); + dev->stats.rx_length_errors++; + goto err_len; + } rcu_read_lock(); xdp_prog = rcu_dereference(rq->xdp_prog); if (xdp_prog) { @@ -761,6 +767,7 @@ err: err_xdp: rcu_read_unlock(); stats->xdp_drops++; +err_len: stats->drops++; put_page(page); xdp_xmit: @@ -814,6 +821,12 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, head_skb = NULL; stats->bytes += len - vi->hdr_len; + if (unlikely(len > truesize)) { + pr_debug("%s: rx error: len %u exceeds truesize %lu\n", + dev->name, len, (unsigned long)ctx); + dev->stats.rx_length_errors++; + goto err_skb; + } rcu_read_lock(); xdp_prog = rcu_dereference(rq->xdp_prog); if (xdp_prog) { @@ -938,13 +951,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, } rcu_read_unlock(); - if (unlikely(len > truesize)) { - pr_debug("%s: rx error: len %u exceeds truesize %lu\n", - dev->name, len, (unsigned long)ctx); - dev->stats.rx_length_errors++; - goto err_skb; - } - head_skb = page_to_skb(vi, rq, page, offset, len, truesize, !xdp_prog, metasize); curr_skb = head_skb; -- 2.30.2