[PATCH] can: kvaser_usb: check number of channels returned by HW

[PATCH] can: kvaser_usb: check number of channels returned by HW

[Olivier Sobrie]

It is needed to check the number of channels returned by the HW
because it cannot be greater than MAX_NET_DEVICES otherwise
it will crash.

Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
---
 drivers/net/can/usb/kvaser_usb.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index 4b2d5ed..cc3df8a 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c
@@ -474,6 +474,8 @@ static int kvaser_usb_get_card_info(struct kvaser_usb *dev)
 		return err;
 
 	dev->nchannels = msg.u.cardinfo.nchannels;
+	if (dev->nchannels > MAX_NET_DEVICES)
+		return -EINVAL;
 
 	return 0;
 }
-- 
1.7.9.5

Re: [PATCH] can: kvaser_usb: check number of channels returned by HW

[Marc Kleine-Budde]

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On 02/11/2014 11:01 AM, Olivier Sobrie wrote:
> It is needed to check the number of channels returned by the HW
> because it cannot be greater than MAX_NET_DEVICES otherwise
> it will crash.
>
> Signed-off-by: Olivier Sobrie <olivier@sobrie.be>

Does this bug occur on any kvaser USB hardware?
However, I think, I'll add stable on Cc

Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
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Re: [PATCH] can: kvaser_usb: check number of channels returned by HW

[Olivier Sobrie]

Hello Marc,

On Tue, Feb 11, 2014 at 11:09:57AM +0100, Marc Kleine-Budde wrote:
> On 02/11/2014 11:01 AM, Olivier Sobrie wrote:
> > It is needed to check the number of channels returned by the HW
> > because it cannot be greater than MAX_NET_DEVICES otherwise
> > it will crash.
> >
> > Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
> 
> Does this bug occur on any kvaser USB hardware?

I never see it with the devices I have and nobody reported me a problem
regarding this. I found this bug by chance while I was looking to add
support for Kvaser device from usbcanII family.

> However, I think, I'll add stable on Cc

Good idea :-)
Thank you,

-- 
Olivier

Re: [PATCH] can: kvaser_usb: check number of channels returned by HW

[Marc Kleine-Budde]

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On 02/11/2014 01:33 PM, Olivier Sobrie wrote:
> Hello Marc,
> 
> On Tue, Feb 11, 2014 at 11:09:57AM +0100, Marc Kleine-Budde wrote:
>> On 02/11/2014 11:01 AM, Olivier Sobrie wrote:
>>> It is needed to check the number of channels returned by the HW
>>> because it cannot be greater than MAX_NET_DEVICES otherwise
>>> it will crash.
>>>
>>> Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
>>
>> Does this bug occur on any kvaser USB hardware?
> 
> I never see it with the devices I have and nobody reported me a problem
> regarding this. I found this bug by chance while I was looking to add
> support for Kvaser device from usbcanII family.

Tnx, I'll include the patch in my next pull request to David.

Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |


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[PATCH] can: kvaser_usb: check number of channels returned by HW

[Marc Kleine-Budde]

From: Olivier Sobrie <olivier@sobrie.be>

It is needed to check the number of channels returned by the HW because it
cannot be greater than MAX_NET_DEVICES otherwise it will crash.

Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/net/can/usb/kvaser_usb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index 6c859bb..e77d110 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c
@@ -473,6 +473,8 @@ static int kvaser_usb_get_card_info(struct kvaser_usb *dev)
 		return err;
 
 	dev->nchannels = msg.u.cardinfo.nchannels;
+	if (dev->nchannels > MAX_NET_DEVICES)
+		return -EINVAL;
 
 	return 0;
 }
-- 
1.8.5.3