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=-13.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 95B0FC433DF for ; Wed, 8 Jul 2020 09:21:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6892C20658 for ; Wed, 8 Jul 2020 09:21:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594200072; bh=VScd6SOtf3GWYrNh+gwwO+ZPM/b0ryaPhtaMfG++Rtg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=o0R//z18ArsmMS+M3D1AVvDkVzrLhD3vQDzpA9styJqKlS59JPy0VwC+c8xAPD0Mg Tha7GOzUiT3r4vYmdwfXKYnX425592z5LMdDuLMDqaIb82bX2uye9LrfNIBVuSCTnm LbrUhI3nV9WBsFyvJOLrmo1WARfC1+YuycXOeMZ0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726184AbgGHJVM (ORCPT ); Wed, 8 Jul 2020 05:21:12 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:38624 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726144AbgGHJVL (ORCPT ); Wed, 8 Jul 2020 05:21:11 -0400 Received: by mail-wr1-f66.google.com with SMTP id z13so48074321wrw.5; Wed, 08 Jul 2020 02:21:08 -0700 (PDT) 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:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Rb/DISg/IR/8ZOl/IE2H8Q9xJVvB/ooWq5NRbEkO++k=; b=cUduO+oiodiARdM2km/qE0t+NAYN0Df8S8aEwRfqoV56V2RqmSWZ8Pq66S6/5lwkmg ogwX9EFWiVboL93iQtKZR5hSyU0Nkbg1i2a8zdX+oLQWLdgsMEJt9IdN0+VzYfD1oSjv nLSXkODFyYnOCvMsOB1h8POIkd6t9foSAT9/VAGYfTD6HAOMnBeXyvLFvVBtJ/oDHWmE Os1k3eh3PM1MKNJDA0n6Fxj+0MU2YlAbrWt2J02WUzvbv4myNNMIYV+dxBv1tqKQyLpC qWtyV8ALQwLK8E0mtRylVUM7bk6LIsB0NSGrQL7TwPgb2MgYLyKqC5FNsfPXqk/lElew n0hg== X-Gm-Message-State: AOAM532CfVKgc/O03G0YXuM5gEb1JAlEVLSVEcB+PxusrjsbnIo/i8kp g+bX/2uycnIbUOx2WBmmRjY= X-Google-Smtp-Source: ABdhPJynLqDiqZcVUZmnTnK/VIflWX22q4P6W+N+0piDUj3pr5Ba4Saaj5PIoCpujsjnALWMbmobjg== X-Received: by 2002:adf:edc6:: with SMTP id v6mr58130575wro.413.1594200068120; Wed, 08 Jul 2020 02:21:08 -0700 (PDT) Received: from liuwe-devbox-debian-v2 ([51.145.34.42]) by smtp.gmail.com with ESMTPSA id g145sm6530197wmg.23.2020.07.08.02.21.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Jul 2020 02:21:07 -0700 (PDT) Date: Wed, 8 Jul 2020 09:21:05 +0000 From: Wei Liu To: Nathan Chancellor Cc: t-mabelt@microsoft.com, kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, wei.liu@kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, mikelley@microsoft.com, parri.andrea@gmail.com, Andres Beltran , "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi@vger.kernel.org Subject: Re: [PATCH v4 2/3] scsi: storvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening Message-ID: <20200708092105.7af7sf2olpaysh33@liuwe-devbox-debian-v2> References: <20200701001221.2540-1-lkmlabelt@gmail.com> <20200701001221.2540-3-lkmlabelt@gmail.com> <20200707234700.GA218@Ryzen-9-3900X.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200707234700.GA218@Ryzen-9-3900X.localdomain> User-Agent: NeoMutt/20180716 Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On Tue, Jul 07, 2020 at 04:47:00PM -0700, Nathan Chancellor wrote: > Hi Andres, > > On Tue, Jun 30, 2020 at 08:12:20PM -0400, Andres Beltran wrote: > > Currently, pointers to guest memory are passed to Hyper-V as > > transaction IDs in storvsc. In the face of errors or malicious > > behavior in Hyper-V, storvsc should not expose or trust the transaction > > IDs returned by Hyper-V to be valid guest memory addresses. Instead, > > use small integers generated by vmbus_requestor as requests > > (transaction) IDs. > > > > Cc: "James E.J. Bottomley" > > Cc: "Martin K. Petersen" > > Cc: linux-scsi@vger.kernel.org > > Signed-off-by: Andres Beltran > > Reviewed-by: Michael Kelley > > --- > > Changes in v2: > > - Add casts to unsigned long to fix warnings on 32bit. > > > > drivers/scsi/storvsc_drv.c | 85 +++++++++++++++++++++++++++++++++----- > > 1 file changed, 74 insertions(+), 11 deletions(-) > > > > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c > > index 624467e2590a..6d2df1f0fe6d 100644 > > --- a/drivers/scsi/storvsc_drv.c > > +++ b/drivers/scsi/storvsc_drv.c > > @@ -399,6 +399,7 @@ static int storvsc_timeout = 180; > > static struct scsi_transport_template *fc_transport_template; > > #endif > > > > +static struct scsi_host_template scsi_driver; > > static void storvsc_on_channel_callback(void *context); > > > > #define STORVSC_MAX_LUNS_PER_TARGET 255 > > @@ -698,6 +699,12 @@ static void handle_sc_creation(struct vmbus_channel *new_sc) > > > > memset(&props, 0, sizeof(struct vmstorage_channel_properties)); > > > > + /* > > + * The size of vmbus_requestor is an upper bound on the number of requests > > + * that can be in-progress at any one time across all channels. > > + */ > > + new_sc->rqstor_size = scsi_driver.can_queue; > > + > > ret = vmbus_open(new_sc, > > storvsc_ringbuffer_size, > > storvsc_ringbuffer_size, > > @@ -726,6 +733,7 @@ static void handle_multichannel_storage(struct hv_device *device, int max_chns) > > struct storvsc_cmd_request *request; > > struct vstor_packet *vstor_packet; > > int ret, t; > > + u64 rqst_id; > > > > /* > > * If the number of CPUs is artificially restricted, such as > > @@ -760,14 +768,23 @@ static void handle_multichannel_storage(struct hv_device *device, int max_chns) > > vstor_packet->flags = REQUEST_COMPLETION_FLAG; > > vstor_packet->sub_channel_count = num_sc; > > > > + rqst_id = vmbus_next_request_id(&device->channel->requestor, > > + (unsigned long)request); > > + if (rqst_id == VMBUS_RQST_ERROR) { > > + dev_err(dev, "No request id available\n"); > > + return; > > + } > > + > > ret = vmbus_sendpacket(device->channel, vstor_packet, > > (sizeof(struct vstor_packet) - > > vmscsi_size_delta), > > - (unsigned long)request, > > + rqst_id, > > VM_PKT_DATA_INBAND, > > VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); > > > > if (ret != 0) { > > + /* Reclaim request ID to avoid leak of IDs */ > > + vmbus_request_addr(&device->channel->requestor, rqst_id); > > dev_err(dev, "Failed to create sub-channel: err=%d\n", ret); > > return; > > } > > @@ -818,20 +835,31 @@ static int storvsc_execute_vstor_op(struct hv_device *device, > > { > > struct vstor_packet *vstor_packet; > > int ret, t; > > + u64 rqst_id; > > > > vstor_packet = &request->vstor_packet; > > > > init_completion(&request->wait_event); > > vstor_packet->flags = REQUEST_COMPLETION_FLAG; > > > > + rqst_id = vmbus_next_request_id(&device->channel->requestor, > > + (unsigned long)request); > > + if (rqst_id == VMBUS_RQST_ERROR) { > > + dev_err(&device->device, "No request id available\n"); > > + return -EAGAIN; > > + } > > + > > ret = vmbus_sendpacket(device->channel, vstor_packet, > > (sizeof(struct vstor_packet) - > > vmscsi_size_delta), > > - (unsigned long)request, > > + rqst_id, > > VM_PKT_DATA_INBAND, > > VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); > > - if (ret != 0) > > + if (ret != 0) { > > + /* Reclaim request ID to avoid leak of IDs */ > > + vmbus_request_addr(&device->channel->requestor, rqst_id); > > return ret; > > + } > > > > t = wait_for_completion_timeout(&request->wait_event, 5*HZ); > > if (t == 0) > > @@ -1233,9 +1261,17 @@ static void storvsc_on_channel_callback(void *context) > > foreach_vmbus_pkt(desc, channel) { > > void *packet = hv_pkt_data(desc); > > struct storvsc_cmd_request *request; > > + u64 cmd_rqst; > > > > - request = (struct storvsc_cmd_request *) > > - ((unsigned long)desc->trans_id); > > + cmd_rqst = vmbus_request_addr(&channel->requestor, > > + desc->trans_id); > > + if (cmd_rqst == VMBUS_RQST_ERROR) { > > + dev_err(&device->device, > > + "Incorrect transaction id\n"); > > + continue; > > + } > > + > > + request = (struct storvsc_cmd_request *)(unsigned long)cmd_rqst; > > > > if (request == &stor_device->init_request || > > request == &stor_device->reset_request) { > > @@ -1256,6 +1292,12 @@ static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size, > > > > memset(&props, 0, sizeof(struct vmstorage_channel_properties)); > > > > + /* > > + * The size of vmbus_requestor is an upper bound on the number of requests > > + * that can be in-progress at any one time across all channels. > > + */ > > + device->channel->rqstor_size = scsi_driver.can_queue; > > + > > ret = vmbus_open(device->channel, > > ring_size, > > ring_size, > > @@ -1369,6 +1411,7 @@ static int storvsc_do_io(struct hv_device *device, > > int ret = 0; > > const struct cpumask *node_mask; > > int tgt_cpu; > > + u64 rqst_id; > > > > vstor_packet = &request->vstor_packet; > > stor_device = get_out_stor_device(device); > > @@ -1463,6 +1506,13 @@ static int storvsc_do_io(struct hv_device *device, > > > > vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB; > > > > + rqst_id = vmbus_next_request_id(&outgoing_channel->requestor, > > + (unsigned long)request); > > + if (rqst_id == VMBUS_RQST_ERROR) { > > + dev_err(&device->device, "No request id available\n"); > > + return -EAGAIN; > > + } > > + > > if (request->payload->range.len) { > > > > ret = vmbus_sendpacket_mpb_desc(outgoing_channel, > > @@ -1470,18 +1520,21 @@ static int storvsc_do_io(struct hv_device *device, > > vstor_packet, > > (sizeof(struct vstor_packet) - > > vmscsi_size_delta), > > - (unsigned long)request); > > + rqst_id); > > } else { > > ret = vmbus_sendpacket(outgoing_channel, vstor_packet, > > (sizeof(struct vstor_packet) - > > vmscsi_size_delta), > > - (unsigned long)request, > > + rqst_id, > > VM_PKT_DATA_INBAND, > > VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); > > } > > > > - if (ret != 0) > > + if (ret != 0) { > > + /* Reclaim request ID to avoid leak of IDs */ > > + vmbus_request_addr(&outgoing_channel->requestor, rqst_id); > > return ret; > > + } > > > > atomic_inc(&stor_device->num_outstanding_req); > > > > @@ -1562,7 +1615,7 @@ static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd) > > struct storvsc_cmd_request *request; > > struct vstor_packet *vstor_packet; > > int ret, t; > > - > > + u64 rqst_id; > > > > stor_device = get_out_stor_device(device); > > if (!stor_device) > > @@ -1577,14 +1630,24 @@ static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd) > > vstor_packet->flags = REQUEST_COMPLETION_FLAG; > > vstor_packet->vm_srb.path_id = stor_device->path_id; > > > > + rqst_id = vmbus_next_request_id(&device->channel->requestor, > > + (unsigned long)&stor_device->reset_request); > > + if (rqst_id == VMBUS_RQST_ERROR) { > > + dev_err(&device->device, "No request id available\n"); > > + return FAILED; > > + } > > + > > ret = vmbus_sendpacket(device->channel, vstor_packet, > > (sizeof(struct vstor_packet) - > > vmscsi_size_delta), > > - (unsigned long)&stor_device->reset_request, > > + rqst_id, > > VM_PKT_DATA_INBAND, > > VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); > > - if (ret != 0) > > + if (ret != 0) { > > + /* Reclaim request ID to avoid leak of IDs */ > > + vmbus_request_addr(&device->channel->requestor, rqst_id); > > return FAILED; > > + } > > > > t = wait_for_completion_timeout(&request->wait_event, 5*HZ); > > if (t == 0) > > -- > > 2.25.1 > > > > This patch has landed in linux-next as of next-20200707 and now I can no > longer boot the WSL2 lightweight VM. > > PS C:\Users\natec> wsl -d ubuntu > The virtual machine or container was forcefully exited. > > $ git bisect log > # bad: [5b2a702f85b3285fcde0309aadacc13a36c70fc7] Add linux-next specific files for 20200707 > # good: [bfe91da29bfad9941d5d703d45e29f0812a20724] Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm > git bisect start 'origin/master' 'origin/stable' > # good: [885913a4d03f7f5fbd2c75121ea8c42f58185cc5] Merge remote-tracking branch 'crypto/master' > git bisect good 885913a4d03f7f5fbd2c75121ea8c42f58185cc5 > # good: [4a902a00a463f60b1630577a32e142800707c576] Merge remote-tracking branch 'regulator/for-next' > git bisect good 4a902a00a463f60b1630577a32e142800707c576 > # good: [e48c950eb83e19d532ea49112211b01c6210377a] Merge remote-tracking branch 'thunderbolt/next' > git bisect good e48c950eb83e19d532ea49112211b01c6210377a > # good: [0a299abc3a2127d9711517904a1e5c751985b5a5] Merge remote-tracking branch 'rtc/rtc-next' > git bisect good 0a299abc3a2127d9711517904a1e5c751985b5a5 > # good: [6de62f5629875029fbd8d79d7fa9c45e8dbea966] kcov: make some symbols static > git bisect good 6de62f5629875029fbd8d79d7fa9c45e8dbea966 > # bad: [9103b615924bf7594a7651a9777e0cf177201dbd] Merge remote-tracking branch 'auxdisplay/auxdisplay' > git bisect bad 9103b615924bf7594a7651a9777e0cf177201dbd > # good: [ed0e825a5c0f00aec12f79e8aef4b37dbb5a94f1] Merge remote-tracking branch 'kspp/for-next/kspp' > git bisect good ed0e825a5c0f00aec12f79e8aef4b37dbb5a94f1 > # good: [563bebf9d7625b579a13b79a4981fdd3097d9bce] Merge remote-tracking branch 'nvmem/for-next' > git bisect good 563bebf9d7625b579a13b79a4981fdd3097d9bce > # good: [efd8e353a542e79995681d98a4849eeeb1ce3809] Drivers: hv: vmbus: Add vmbus_requestor data structure for VMBus hardening > git bisect good efd8e353a542e79995681d98a4849eeeb1ce3809 > # good: [27586ca786a729cda6c807621a1494900a56e7bc] XArray: Handle retry entries within xas_find_marked > git bisect good 27586ca786a729cda6c807621a1494900a56e7bc > # bad: [11478f56f20e3be6d11043b501f3090375af4492] hv_netvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening > git bisect bad 11478f56f20e3be6d11043b501f3090375af4492 > # bad: [8e569d774e1e73afabf1fbf40d11fcb8462ddffa] scsi: storvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardeninggit bisect bad 8e569d774e1e73afabf1fbf40d11fcb8462ddffa > # first bad commit: [8e569d774e1e73afabf1fbf40d11fcb8462ddffa] scsi: storvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening > > If I revert this commit, everything works fine: > > PS C:\Users\natec> wsl --shutdown > PS C:\Users\natec> wsl -d ubuntu -- /bin/bash > nathan@Ryzen-9-3900X:/mnt/c/Users/natec$ cat /proc/version > Linux version 5.8.0-rc4-next-20200707-microsoft-standard+ (nathan@Ryzen-9-3900X) (gcc (Ubuntu 9.3.0-10ubuntu2) 9.3.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #1 SMP Tue Jul 7 16:35:06 MST 2020 > nathan@Ryzen-9-3900X:/mnt/c/Users/natec$ git -C ~/src/linux-next lo -2 > 0ff017dff922 (HEAD -> master) Revert "scsi: storvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening" > 5b2a702f85b3 (tag: next-20200707, origin/master, origin/HEAD) Add linux-next specific files for 20200707 > nathan@Ryzen-9-3900X:/mnt/c/Users/natec$ > > The kernel was built using the following commands: > > $ mkdir -p out/x86_64 > > $ curl -LSso out/x86_64/.config https://github.com/microsoft/WSL2-Linux-Kernel/raw/linux-msft-wsl-4.19.y/Microsoft/config-wsl > > $ scripts/config --file out/x86_64/.config -d RAID6_PQ_BENCHMARK -e NET_9P_VIRTIO > > $ make -skj"$(nproc)" O=out/x86_64 olddefconfig bzImage > > I don't really know how to get more information than this as WSL seems > rather opaque but I am happy to provide any information. Linux kernel uses Hyper-V's crash reporting facility to spit out information when it dies. It is said that you can see that information in the "Event Viewer" program. (I've never tried this though -- not using WSL2) Wei. > > Cheers, > Nathan