All of lore.kernel.org
 help / color / mirror / Atom feed
From: Andi Kleen <ak@linux.intel.com>
To: "Kuppuswamy,
	Sathyanarayanan"  <sathyanarayanan.kuppuswamy@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Borislav Petkov <bp@alien8.de>, X86 ML <x86@kernel.org>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	Andreas Noever <andreas.noever@gmail.com>,
	Michael Jamet <michael.jamet@intel.com>,
	Yehezkel Bernat <YehezkelShB@gmail.com>,
	"Rafael J . Wysocki" <rafael@kernel.org>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Jason Wang <jasowang@redhat.com>,
	Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux PCI <linux-pci@vger.kernel.org>,
	USB list <linux-usb@vger.kernel.org>,
	virtualization@lists.linux-foundation.org
Subject: Re: [PATCH v2 4/6] virtio: Initialize authorized attribute for confidential guest
Date: Thu, 30 Sep 2021 12:30:23 -0700	[thread overview]
Message-ID: <291d5e03-ccaa-3a73-cdcd-66cbe80fede1@linux.intel.com> (raw)
In-Reply-To: <1cfdce51-6bb4-f7af-a86b-5854b6737253@linux.intel.com>


On 9/30/2021 12:04 PM, Kuppuswamy, Sathyanarayanan wrote:
>
>
> On 9/30/21 8:23 AM, Greg Kroah-Hartman wrote:
>> On Thu, Sep 30, 2021 at 08:18:18AM -0700, Kuppuswamy, Sathyanarayanan 
>> wrote:
>>>
>>>
>>> On 9/30/21 6:36 AM, Dan Williams wrote:
>>>>> And in particular, not all virtio drivers are hardened -
>>>>> I think at this point blk and scsi drivers have been hardened - so
>>>>> treating them all the same looks wrong.
>>>> My understanding was that they have been audited, Sathya?
>>>
>>> Yes, AFAIK, it has been audited. Andi also submitted some patches
>>> related to it. Andi, can you confirm.
>>
>> What is the official definition of "audited"?
>
>
> In our case (Confidential Computing platform), the host is an un-trusted
> entity. So any interaction with host from the drivers will have to be
> protected against the possible attack from the host. For example, if we
> are accessing a memory based on index value received from host, we have
> to make sure it does not lead to out of bound access or when sharing the
> memory with the host, we need to make sure only the required region is
> shared with the host and the memory is un-shared after use properly.
>
> Elena can share more details, but it was achieved with static analysis
> and fuzzing. Here is a presentation she is sharing about the work at the
> Linux Security Summit:
> https://static.sched.com/hosted_files/lssna2021/b6/LSS-HardeningLinuxGuestForCCC.pdf 
>
>
> Andi, can talk more about the specific driver changes that came out of 
> this
> effort.

The original virtio was quite easy to exploit because it put its free 
list into the shared ring buffer.

We had a patchkit to harden virtio originally, but after some discussion 
we instead switched to Jason Wang's patchkit to move the virtio metadata 
into protected memory, which fixed near all of the issues. These patches 
have been already merged. There is one additional patch to limit the 
virtio modes.

There's an ongoing effort to audit (mostly finished I believe) and fuzz 
the three virtio drivers (fuzzing is still ongoing).

There was also a range of changes outside virtio for code outside the 
device model. Most of it was just disabling it though.

-Andi


WARNING: multiple messages have this Message-ID
From: Andi Kleen <ak@linux.intel.com>
To: "Kuppuswamy,
	Sathyanarayanan" <sathyanarayanan.kuppuswamy@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>,
	Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Michael Jamet <michael.jamet@intel.com>,
	Linux PCI <linux-pci@vger.kernel.org>, X86 ML <x86@kernel.org>,
	virtualization@lists.linux-foundation.org,
	Yehezkel Bernat <YehezkelShB@gmail.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Andreas Noever <andreas.noever@gmail.com>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Dan Williams <dan.j.williams@intel.com>,
	USB list <linux-usb@vger.kernel.org>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Rafael J . Wysocki" <rafael@kernel.org>
Subject: Re: [PATCH v2 4/6] virtio: Initialize authorized attribute for confidential guest
Date: Thu, 30 Sep 2021 12:30:23 -0700	[thread overview]
Message-ID: <291d5e03-ccaa-3a73-cdcd-66cbe80fede1@linux.intel.com> (raw)
In-Reply-To: <1cfdce51-6bb4-f7af-a86b-5854b6737253@linux.intel.com>


On 9/30/2021 12:04 PM, Kuppuswamy, Sathyanarayanan wrote:
>
>
> On 9/30/21 8:23 AM, Greg Kroah-Hartman wrote:
>> On Thu, Sep 30, 2021 at 08:18:18AM -0700, Kuppuswamy, Sathyanarayanan 
>> wrote:
>>>
>>>
>>> On 9/30/21 6:36 AM, Dan Williams wrote:
>>>>> And in particular, not all virtio drivers are hardened -
>>>>> I think at this point blk and scsi drivers have been hardened - so
>>>>> treating them all the same looks wrong.
>>>> My understanding was that they have been audited, Sathya?
>>>
>>> Yes, AFAIK, it has been audited. Andi also submitted some patches
>>> related to it. Andi, can you confirm.
>>
>> What is the official definition of "audited"?
>
>
> In our case (Confidential Computing platform), the host is an un-trusted
> entity. So any interaction with host from the drivers will have to be
> protected against the possible attack from the host. For example, if we
> are accessing a memory based on index value received from host, we have
> to make sure it does not lead to out of bound access or when sharing the
> memory with the host, we need to make sure only the required region is
> shared with the host and the memory is un-shared after use properly.
>
> Elena can share more details, but it was achieved with static analysis
> and fuzzing. Here is a presentation she is sharing about the work at the
> Linux Security Summit:
> https://static.sched.com/hosted_files/lssna2021/b6/LSS-HardeningLinuxGuestForCCC.pdf 
>
>
> Andi, can talk more about the specific driver changes that came out of 
> this
> effort.

The original virtio was quite easy to exploit because it put its free 
list into the shared ring buffer.

We had a patchkit to harden virtio originally, but after some discussion 
we instead switched to Jason Wang's patchkit to move the virtio metadata 
into protected memory, which fixed near all of the issues. These patches 
have been already merged. There is one additional patch to limit the 
virtio modes.

There's an ongoing effort to audit (mostly finished I believe) and fuzz 
the three virtio drivers (fuzzing is still ongoing).

There was also a range of changes outside virtio for code outside the 
device model. Most of it was just disabling it though.

-Andi

_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

  parent reply	other threads:[~2021-09-30 19:30 UTC|newest]

Thread overview: 132+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-30  1:05 [PATCH v2 0/6] Add device filter support Kuppuswamy Sathyanarayanan
2021-09-30  1:05 ` [PATCH v2 1/6] driver core: Move the "authorized" attribute from USB/Thunderbolt to core Kuppuswamy Sathyanarayanan
2021-09-30  1:42   ` Alan Stern
2021-09-30  1:42     ` Alan Stern
2021-09-30  1:55     ` Dan Williams
2021-09-30  1:55       ` Dan Williams
2021-09-30  2:38       ` Kuppuswamy, Sathyanarayanan
2021-09-30  4:59         ` Dan Williams
2021-09-30  4:59           ` Dan Williams
2021-09-30  9:05           ` Rafael J. Wysocki
2021-09-30  9:05             ` Rafael J. Wysocki
2021-09-30 14:59       ` Alan Stern
2021-09-30 14:59         ` Alan Stern
2021-09-30 15:25         ` Dan Williams
2021-09-30 15:25           ` Dan Williams
2021-09-30 11:19   ` Yehezkel Bernat
2021-09-30 15:28     ` Dan Williams
2021-09-30 15:28       ` Dan Williams
2021-09-30 18:25       ` Yehezkel Bernat
2021-09-30 19:04         ` Dan Williams
2021-09-30 19:04           ` Dan Williams
2021-09-30 19:50           ` Kuppuswamy, Sathyanarayanan
2021-09-30 20:23             ` Dan Williams
2021-09-30 20:23               ` Dan Williams
2021-09-30  1:05 ` [PATCH v2 2/6] driver core: Add common support to skip probe for un-authorized devices Kuppuswamy Sathyanarayanan
2021-09-30 10:59   ` Michael S. Tsirkin
2021-09-30 10:59     ` Michael S. Tsirkin
2021-09-30 13:52     ` Greg Kroah-Hartman
2021-09-30 13:52       ` Greg Kroah-Hartman
2021-09-30 14:38       ` Michael S. Tsirkin
2021-09-30 14:38         ` Michael S. Tsirkin
2021-09-30 14:49         ` Greg Kroah-Hartman
2021-09-30 14:49           ` Greg Kroah-Hartman
2021-09-30 15:00           ` Michael S. Tsirkin
2021-09-30 15:00             ` Michael S. Tsirkin
2021-09-30 15:22             ` Greg Kroah-Hartman
2021-09-30 15:22               ` Greg Kroah-Hartman
2021-09-30 17:17               ` Andi Kleen
2021-09-30 17:17                 ` Andi Kleen
2021-09-30 17:23                 ` Greg Kroah-Hartman
2021-09-30 17:23                   ` Greg Kroah-Hartman
2021-09-30 19:15                   ` Andi Kleen
2021-09-30 19:15                     ` Andi Kleen
2021-10-01  6:29                     ` Greg Kroah-Hartman
2021-10-01  6:29                       ` Greg Kroah-Hartman
2021-10-01 15:51                       ` Alan Stern
2021-10-01 15:51                         ` Alan Stern
2021-10-01 15:56                         ` Andi Kleen
2021-10-01 15:56                           ` Andi Kleen
2021-09-30 14:43       ` Alan Stern
2021-09-30 14:43         ` Alan Stern
2021-09-30 14:48         ` Michael S. Tsirkin
2021-09-30 14:48           ` Michael S. Tsirkin
2021-09-30 15:32           ` Alan Stern
2021-09-30 15:32             ` Alan Stern
2021-09-30 15:52             ` Michael S. Tsirkin
2021-09-30 15:52               ` Michael S. Tsirkin
2021-09-30 14:58         ` Michael S. Tsirkin
2021-09-30 14:58           ` Michael S. Tsirkin
2021-09-30 15:35           ` Alan Stern
2021-09-30 15:35             ` Alan Stern
2021-09-30 15:59             ` Michael S. Tsirkin
2021-09-30 15:59               ` Michael S. Tsirkin
2021-09-30 19:23               ` Andi Kleen
2021-09-30 19:23                 ` Andi Kleen
2021-09-30 20:44                 ` Alan Stern
2021-09-30 20:44                   ` Alan Stern
2021-09-30 20:52                   ` Dan Williams
2021-09-30 20:52                     ` Dan Williams
2021-10-01  1:41                     ` Alan Stern
2021-10-01  1:41                       ` Alan Stern
2021-10-01  2:20                       ` Dan Williams
2021-10-01  2:20                         ` Dan Williams
2021-09-30 21:12                   ` Andi Kleen
2021-09-30 21:12                     ` Andi Kleen
2021-09-30  1:05 ` [PATCH v2 3/6] driver core: Allow arch to initialize the authorized attribute Kuppuswamy Sathyanarayanan
2021-09-30  1:05 ` [PATCH v2 4/6] virtio: Initialize authorized attribute for confidential guest Kuppuswamy Sathyanarayanan
2021-09-30 11:03   ` Michael S. Tsirkin
2021-09-30 11:03     ` Michael S. Tsirkin
2021-09-30 13:36     ` Dan Williams
2021-09-30 13:36       ` Dan Williams
2021-09-30 13:49       ` Greg Kroah-Hartman
2021-09-30 13:49         ` Greg Kroah-Hartman
2021-09-30 15:18       ` Kuppuswamy, Sathyanarayanan
2021-09-30 15:20         ` Michael S. Tsirkin
2021-09-30 15:20           ` Michael S. Tsirkin
2021-09-30 15:23           ` Kuppuswamy, Sathyanarayanan
2021-09-30 15:23         ` Greg Kroah-Hartman
2021-09-30 15:23           ` Greg Kroah-Hartman
2021-09-30 19:04           ` Kuppuswamy, Sathyanarayanan
2021-09-30 19:16             ` Kuppuswamy, Sathyanarayanan
2021-09-30 19:30             ` Andi Kleen [this message]
2021-09-30 19:30               ` Andi Kleen
2021-09-30 19:40               ` Kuppuswamy, Sathyanarayanan
2021-10-01  7:03             ` Greg Kroah-Hartman
2021-10-01  7:03               ` Greg Kroah-Hartman
2021-10-01 15:49               ` Andi Kleen
2021-10-01 15:49                 ` Andi Kleen
2021-10-02 11:04                 ` Michael S. Tsirkin
2021-10-02 11:04                   ` Michael S. Tsirkin
2021-10-02 11:14                   ` Greg Kroah-Hartman
2021-10-02 11:14                     ` Greg Kroah-Hartman
2021-10-02 14:20                     ` Andi Kleen
2021-10-02 14:20                       ` Andi Kleen
2021-10-02 14:44                       ` Greg Kroah-Hartman
2021-10-02 14:44                         ` Greg Kroah-Hartman
2021-10-02 18:40                       ` Michael S. Tsirkin
2021-10-02 18:40                         ` Michael S. Tsirkin
2021-10-03  6:40                         ` Greg Kroah-Hartman
2021-10-03  6:40                           ` Greg Kroah-Hartman
2021-10-04 21:04                       ` Dan Williams
2021-10-04 21:04                         ` Dan Williams
2021-10-01 16:13               ` Dan Williams
2021-10-01 16:13                 ` Dan Williams
2021-10-01 16:45                 ` Alan Stern
2021-10-01 16:45                   ` Alan Stern
2021-10-01 18:09                   ` Dan Williams
2021-10-01 18:09                     ` Dan Williams
2021-10-01 19:00                     ` Alan Stern
2021-10-01 19:00                       ` Alan Stern
2021-10-01 19:45                       ` Kuppuswamy, Sathyanarayanan
2021-10-01 19:57                       ` Dan Williams
2021-10-01 19:57                         ` Dan Williams
2021-10-04  5:16                         ` Mika Westerberg
2021-10-05 22:33                           ` Dan Williams
2021-10-05 22:33                             ` Dan Williams
2021-10-06  5:45                             ` Greg Kroah-Hartman
2021-10-06  5:45                               ` Greg Kroah-Hartman
2021-09-30 19:25         ` Andi Kleen
2021-09-30 19:25           ` Andi Kleen
2021-09-30  1:05 ` [PATCH v2 5/6] x86/tdx: Add device filter support for x86 TDX guest platform Kuppuswamy Sathyanarayanan
2021-09-30  1:05 ` [PATCH v2 6/6] PCI: Initialize authorized attribute for confidential guest Kuppuswamy Sathyanarayanan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=291d5e03-ccaa-3a73-cdcd-66cbe80fede1@linux.intel.com \
    --to=ak@linux.intel.com \
    --cc=YehezkelShB@gmail.com \
    --cc=andreas.noever@gmail.com \
    --cc=bhelgaas@google.com \
    --cc=bp@alien8.de \
    --cc=corbet@lwn.net \
    --cc=dan.j.williams@intel.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jasowang@redhat.com \
    --cc=knsathya@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=michael.jamet@intel.com \
    --cc=mika.westerberg@linux.intel.com \
    --cc=mingo@redhat.com \
    --cc=mst@redhat.com \
    --cc=rafael@kernel.org \
    --cc=sathyanarayanan.kuppuswamy@linux.intel.com \
    --cc=tglx@linutronix.de \
    --cc=virtualization@lists.linux-foundation.org \
    --cc=x86@kernel.org \
    --subject='Re: [PATCH v2 4/6] virtio: Initialize authorized attribute for confidential guest' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.