2022-08-29 07:50:41

by Maxime Coquelin

[permalink] [raw]
Subject: [PATCH v2] vduse: prevent uninitialized memory accesses

If the VDUSE application provides a smaller config space
than the driver expects, the driver may use uninitialized
memory from the stack.

This patch prevents it by initializing the buffer passed by
the driver to store the config value.

This fix addresses CVE-2022-2308.

Cc: [email protected]
Cc: [email protected] # v5.15+
Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")

Acked-by: Jason Wang <[email protected]>
Signed-off-by: Maxime Coquelin <[email protected]>
---
drivers/vdpa/vdpa_user/vduse_dev.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
index 41c0b29739f1..35dceee3ed56 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -673,10 +673,15 @@ static void vduse_vdpa_get_config(struct vdpa_device *vdpa, unsigned int offset,
{
struct vduse_dev *dev = vdpa_to_vduse(vdpa);

- if (offset > dev->config_size ||
- len > dev->config_size - offset)
+ /* Initialize the buffer in case of partial copy. */
+ memset(buf, 0, len);
+
+ if (offset > dev->config_size)
return;

+ if (len > dev->config_size - offset)
+ len = dev->config_size - offset;
+
memcpy(buf, dev->config + offset, len);
}

--
2.37.2


2022-08-29 08:07:43

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: [PATCH v2] vduse: prevent uninitialized memory accesses

On Mon, Aug 29, 2022 at 09:34:24AM +0200, Maxime Coquelin wrote:
> If the VDUSE application provides a smaller config space
> than the driver expects, the driver may use uninitialized
> memory from the stack.
>
> This patch prevents it by initializing the buffer passed by
> the driver to store the config value.
>
> This fix addresses CVE-2022-2308.
>
> Cc: [email protected]
> Cc: [email protected] # v5.15+
> Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
>
> Acked-by: Jason Wang <[email protected]>
> Signed-off-by: Maxime Coquelin <[email protected]>

Please no blank line above the Acked-by: line here if possible.

thanks,

greg k-h

2022-08-29 11:03:04

by Yongji Xie

[permalink] [raw]
Subject: Re: [PATCH v2] vduse: prevent uninitialized memory accesses

On Mon, Aug 29, 2022 at 3:34 PM Maxime Coquelin
<[email protected]> wrote:
>
> If the VDUSE application provides a smaller config space
> than the driver expects, the driver may use uninitialized
> memory from the stack.
>
> This patch prevents it by initializing the buffer passed by
> the driver to store the config value.
>
> This fix addresses CVE-2022-2308.
>
> Cc: [email protected]
> Cc: [email protected] # v5.15+
> Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
>
> Acked-by: Jason Wang <[email protected]>
> Signed-off-by: Maxime Coquelin <[email protected]>

Reviewed-by: Xie Yongji <[email protected]>

Thanks,
Yongji

2022-08-31 15:20:02

by Maxime Coquelin

[permalink] [raw]
Subject: Re: [PATCH v2] vduse: prevent uninitialized memory accesses

On 8/29/22 09:48, Greg KH wrote:
> On Mon, Aug 29, 2022 at 09:34:24AM +0200, Maxime Coquelin wrote:
>> If the VDUSE application provides a smaller config space
>> than the driver expects, the driver may use uninitialized
>> memory from the stack.
>>
>> This patch prevents it by initializing the buffer passed by
>> the driver to store the config value.
>>
>> This fix addresses CVE-2022-2308.
>>
>> Cc: [email protected]
>> Cc: [email protected] # v5.15+
>> Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
>>
>> Acked-by: Jason Wang <[email protected]>
>> Signed-off-by: Maxime Coquelin <[email protected]>
>
> Please no blank line above the Acked-by: line here if possible.

Sure.

Jason, do you prefer I post a new revision with this single change or
you will handle it while applying? Either way is fine to me.

Thanks,
Maxime

> thanks,
>
> greg k-h
>

2022-08-31 15:55:31

by Michael S. Tsirkin

[permalink] [raw]
Subject: Re: [PATCH v2] vduse: prevent uninitialized memory accesses

On Wed, Aug 31, 2022 at 05:01:11PM +0200, Maxime Coquelin wrote:
> On 8/29/22 09:48, Greg KH wrote:
> > On Mon, Aug 29, 2022 at 09:34:24AM +0200, Maxime Coquelin wrote:
> > > If the VDUSE application provides a smaller config space
> > > than the driver expects, the driver may use uninitialized
> > > memory from the stack.
> > >
> > > This patch prevents it by initializing the buffer passed by
> > > the driver to store the config value.
> > >
> > > This fix addresses CVE-2022-2308.
> > >
> > > Cc: [email protected]
> > > Cc: [email protected] # v5.15+
> > > Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
> > >
> > > Acked-by: Jason Wang <[email protected]>
> > > Signed-off-by: Maxime Coquelin <[email protected]>
> >
> > Please no blank line above the Acked-by: line here if possible.
>
> Sure.
>
> Jason, do you prefer I post a new revision with this single change or
> you will handle it while applying? Either way is fine to me.
>
> Thanks,
> Maxime

Repost pls, easier.

> > thanks,
> >
> > greg k-h
> >

2022-08-31 16:20:09

by Michael S. Tsirkin

[permalink] [raw]
Subject: Re: [PATCH v2] vduse: prevent uninitialized memory accesses

On Wed, Aug 31, 2022 at 05:01:11PM +0200, Maxime Coquelin wrote:
> On 8/29/22 09:48, Greg KH wrote:
> > On Mon, Aug 29, 2022 at 09:34:24AM +0200, Maxime Coquelin wrote:
> > > If the VDUSE application provides a smaller config space
> > > than the driver expects, the driver may use uninitialized
> > > memory from the stack.
> > >
> > > This patch prevents it by initializing the buffer passed by
> > > the driver to store the config value.
> > >
> > > This fix addresses CVE-2022-2308.
> > >
> > > Cc: [email protected]
> > > Cc: [email protected] # v5.15+
> > > Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
> > >
> > > Acked-by: Jason Wang <[email protected]>
> > > Signed-off-by: Maxime Coquelin <[email protected]>
> >
> > Please no blank line above the Acked-by: line here if possible.
>
> Sure.
>
> Jason, do you prefer I post a new revision with this single change or
> you will handle it while applying? Either way is fine to me.
>
> Thanks,
> Maxime

I queue these normally.

> > thanks,
> >
> > greg k-h
> >

2022-08-31 16:20:48

by Maxime Coquelin

[permalink] [raw]
Subject: Re: [PATCH v2] vduse: prevent uninitialized memory accesses



On 8/31/22 17:46, Michael S. Tsirkin wrote:
> On Wed, Aug 31, 2022 at 05:01:11PM +0200, Maxime Coquelin wrote:
>> On 8/29/22 09:48, Greg KH wrote:
>>> On Mon, Aug 29, 2022 at 09:34:24AM +0200, Maxime Coquelin wrote:
>>>> If the VDUSE application provides a smaller config space
>>>> than the driver expects, the driver may use uninitialized
>>>> memory from the stack.
>>>>
>>>> This patch prevents it by initializing the buffer passed by
>>>> the driver to store the config value.
>>>>
>>>> This fix addresses CVE-2022-2308.
>>>>
>>>> Cc: [email protected]
>>>> Cc: [email protected] # v5.15+
>>>> Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace")
>>>>
>>>> Acked-by: Jason Wang <[email protected]>
>>>> Signed-off-by: Maxime Coquelin <[email protected]>
>>>
>>> Please no blank line above the Acked-by: line here if possible.
>>
>> Sure.
>>
>> Jason, do you prefer I post a new revision with this single change or
>> you will handle it while applying? Either way is fine to me.
>>
>> Thanks,
>> Maxime
>
> I queue these normally.

Ok, I'm preparing the V2.

Thanks,
Maxime

>>> thanks,
>>>
>>> greg k-h
>>>
>