linux-kernel - Re: [PATCH net V3] virtio-net: validate features during probe

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <546D948C.7020105@redhat.com>
Date:	Thu, 20 Nov 2014 15:13:16 +0800
From:	Jason Wang <jasowang@...hat.com>
To:	"Michael S. Tsirkin" <mst@...hat.com>
CC:	rusty@...tcorp.com.au, virtualization@...ts.linux-foundation.org,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
	Cornelia Huck <cornelia.huck@...ibm.com>,
	Wanlong Gao <gaowanlong@...fujitsu.com>
Subject: Re: [PATCH net V3] virtio-net: validate features during probe

On 11/20/2014 03:02 PM, Michael S. Tsirkin wrote:
> On Thu, Nov 20, 2014 at 02:10:35PM +0800, Jason Wang wrote:
>> We currently trigger BUG when VIRTIO_NET_F_CTRL_VQ
>> is not set but one of features depending on it is.
>> That's not a friendly way to report errors to
>> hypervisors.
>> Let's check, and fail probe instead.
>>
>> Cc: Rusty Russell <rusty@...tcorp.com.au>
>> Cc: Cornelia Huck <cornelia.huck@...ibm.com>
>> Cc: Wanlong Gao <gaowanlong@...fujitsu.com>
>> Signed-off-by: Michael S. Tsirkin <mst@...hat.com>
>> Signed-off-by: Jason Wang <jasowang@...hat.com>
>
> Looks good, minor nits below:
>
>> ---
>> Changes from V2:
>> - only check the features for ctrl vq (this fix the real bug)
>> - better error message and simplify API
>> ---
>>  drivers/net/virtio_net.c | 37 +++++++++++++++++++++++++++++++++++++
>>  1 file changed, 37 insertions(+)
>>
>> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
>> index ec2a8b4..a6bcfce 100644
>> --- a/drivers/net/virtio_net.c
>> +++ b/drivers/net/virtio_net.c
>> @@ -1673,6 +1673,40 @@ static const struct attribute_group virtio_net_mrg_rx_group = {
>>  };
>>  #endif
>>  
>> +static bool virtnet_fail_on_feature(struct virtio_device *vdev,
>> +				    unsigned int fbit,
>> +				    const char *fname, const char *dname)
>> +{
>> +	if (!virtio_has_feature(vdev, fbit))
>> +		return false;
>> +
>> +	dev_err(&vdev->dev, "Hypervisor bug: advertise feature %s but not %s",
> Well we don't know it's a hypervisor. How about:
> Device bug: advertises feature %s but not %s.

Ok.
>> +		fname, dname);
>> +
>> +	return true;
>> +}
>> +
>> +#define VIRTNET_FAIL_ON(vdev, fbit, dbit)			\
>> +	virtnet_fail_on_feature(vdev, fbit, #fbit, #dbit)
> I would pass dbit directly, and supply a string from caller,
> instead if #dbit, this way it can be any string.

Right, this is better.
>> +
>> +static bool virtnet_validate_features(struct virtio_device *vdev)
>> +{
>> +	if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
>> +	    (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
>> +			     VIRTIO_NET_F_CTRL_VQ) ||
>> +	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
>> +			     VIRTIO_NET_F_CTRL_VQ) ||
>> +	     VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
>> +			     VIRTIO_NET_F_TRL_VQ) ||
> Typo: VIRTIO_NET_F_CTRL_VQ.
>
>

Wil fix this and post V4.

Thanks

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/