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=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=no 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 CA734C432C0 for ; Thu, 21 Nov 2019 23:04:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9935B20692 for ; Thu, 21 Nov 2019 23:04:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=netronome-com.20150623.gappssmtp.com header.i=@netronome-com.20150623.gappssmtp.com header.b="Nc6/mbo0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726408AbfKUXE4 (ORCPT ); Thu, 21 Nov 2019 18:04:56 -0500 Received: from mail-lj1-f195.google.com ([209.85.208.195]:47086 "EHLO mail-lj1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725956AbfKUXE4 (ORCPT ); Thu, 21 Nov 2019 18:04:56 -0500 Received: by mail-lj1-f195.google.com with SMTP id e9so5072030ljp.13 for ; Thu, 21 Nov 2019 15:04:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netronome-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :organization:mime-version:content-transfer-encoding; bh=ujSnirx0MMYk1nWbIfrsLRgvcTHBcDKnqPSTu0uZhPM=; b=Nc6/mbo0NU7TqyfZ0KlcWiAFlSVLQv17ZroqrY0RRWkOLd+EX3M0YN/8CWH1eoWDxm 2XpNdcx5yss6p7g5w7yowMTkhd7PhLgYbpaqA/BdiMguJHL7uZ8TFq9ct50g3xAb9MKi uhYApgEyRVoNYA0UGHawQt2+EmxOwKrQGWpeHVB9t/hau3ZCsCa2P8QRC9000TmAfAaU 8WzEu4NDMYH1F3s30mvOmIRvbIfbo2uSIU29VSXlubGOa3SYWiqK5xXIvi3A7I0iz9Ix VUVSNyhYKiy8s/u9kOjcbbaUoswVrPIZdGtdLvMJVR6nLYyPFZUKK98OIX58Vf1LFTdr 8P8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:organization:mime-version:content-transfer-encoding; bh=ujSnirx0MMYk1nWbIfrsLRgvcTHBcDKnqPSTu0uZhPM=; b=rox7N/QTtepYMmAJyApcvF2v2pbUmy0J3bG832FefPF0Fnavg4jhu+oZVwiRN60bCK SQcOJMrLhUxgiJbo/Om+KtoZv/jr8ZDub/R93KHkVK7WbRL0xQmA4SJ/R8JIHH7YukQo AqtX+Rkm4ddLS/TxopwEdf6wIj7EFO7et7HGE7WFSdvFuAUCUOn+7QkFWnPwrbvoDhhZ /0kSCPennGXHuOMupzseq7aQkKCTYEP1HK4dRYn+NlfdJnLUhtZNvPgLaNf2krlrBi6n wRrw+B8OXOM6yWEWLXqRsTm2ksp8bIf5ZXoVsfEv+hB0uRSHPUyx9NEOKq+YYYSn1C/+ 30mg== X-Gm-Message-State: APjAAAVNRPL/Msh+RJlSdGBcFL0leJqWgDLOpninVe8olNjmjTP0jmVU 6qHnnXAjJBzCQ/TrBXPDUScQLw== X-Google-Smtp-Source: APXvYqz0mplj+GIU5C+xgkex6FnLpZY91dYMJ1RaB5pMlahZp9Gr58LPzTcEQ5ePObyFharZ/pSU9g== X-Received: by 2002:a2e:8857:: with SMTP id z23mr10180706ljj.50.1574377493540; Thu, 21 Nov 2019 15:04:53 -0800 (PST) Received: from cakuba.netronome.com ([66.60.152.14]) by smtp.gmail.com with ESMTPSA id i6sm2129075lfo.12.2019.11.21.15.04.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Nov 2019 15:04:53 -0800 (PST) Date: Thu, 21 Nov 2019 15:04:45 -0800 From: Jakub Kicinski To: Haiyang Zhang Cc: sashal@kernel.org, linux-hyperv@vger.kernel.org, netdev@vger.kernel.org, kys@microsoft.com, sthemmin@microsoft.com, olaf@aepfle.de, vkuznets@redhat.com, davem@davemloft.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH net,v2 1/2] hv_netvsc: Fix offset usage in netvsc_send_table() Message-ID: <20191121150445.47fc3358@cakuba.netronome.com> In-Reply-To: <1574372021-29439-2-git-send-email-haiyangz@microsoft.com> References: <1574372021-29439-1-git-send-email-haiyangz@microsoft.com> <1574372021-29439-2-git-send-email-haiyangz@microsoft.com> Organization: Netronome Systems, Ltd. MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On Thu, 21 Nov 2019 13:33:40 -0800, Haiyang Zhang wrote: > To reach the data region, the existing code adds offset in struct > nvsp_5_send_indirect_table on the beginning of this struct. But the > offset should be based on the beginning of its container, > struct nvsp_message. This bug causes the first table entry missing, > and adds an extra zero from the zero pad after the data region. > This can put extra burden on the channel 0. > > So, correct the offset usage. Also add a boundary check to ensure > not reading beyond data region. Please provide a change log at the end of the commit message when posting new version in the future. > Fixes: 5b54dac856cb ("hyperv: Add support for virtual Receive Side Scaling (vRSS)") > Signed-off-by: Haiyang Zhang > > - tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table + > - nvmsg->msg.v5_msg.send_table.offset); > + if (offset > msglen - count * sizeof(u32)) { Can't this underflow now? What if msglen is small? > + netdev_err(ndev, "Received send-table offset too big:%u\n", > + offset); > + return; > + } > + > + tab = (void *)nvmsg + offset; > > for (i = 0; i < count; i++) > net_device_ctx->tx_table[i] = tab[i];