On Thu, Mar 8, 2018 at 4:15 PM, Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote:
>
>
> On 03/08/2018 05:37 AM, Alexander Potapenko wrote:
>>
>> KMSAN reported a use of uninit memory in vhost_net_buf_unproduce()
>> while trying to access n->vqs[VHOST_NET_VQ_TX].rx_ring:
>>
>>
>> ==================================================================
>>
>> Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
>
>
> Please identify bug origin with a Fixes: tag
Fixes: 5990a30510ed1 ("tun/tap: use ptr_ring instead of skb_array")
The above patch introduced rx_ring, but the problem existed before.
> This will tremendously help stable teams that are struggling with many
> backports these days.
>
> Thanks.
>
>
>> ---
>> drivers/vhost/net.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
>> index 610cba276d47..60f1080bffc7 100644
>> --- a/drivers/vhost/net.c
>> +++ b/drivers/vhost/net.c
>> @@ -948,6 +948,7 @@ static int vhost_net_open(struct inode *inode, struct
>> file *f)
>> n->vqs[i].done_idx = 0;
>> n->vqs[i].vhost_hlen = 0;
>> n->vqs[i].sock_hlen = 0;
>> + n->vqs[i].rx_ring = NULL;
>> vhost_net_buf_init(&n->vqs[i].rxq);
>> }
>> vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX);
>>
>
--
Alexander Potapenko
Software Engineer
Google Germany GmbH
Erika-Mann-Straße, 33
80636 München
Geschäftsführer: Paul Manicle, Halimah DeLaine Prado
Registergericht und -nummer: Hamburg, HRB 86891
Sitz der Gesellschaft: Hamburg
