Re: [PATCH net] vhost: validate log when IOTLB is enabled

2018-03-29 Thread Jason Wang
On 2018年03月29日 22:44, Michael S. Tsirkin wrote: On Thu, Mar 29, 2018 at 04:00:04PM +0800, Jason Wang wrote: Vq log_base is the userspace address of bitmap which has nothing to do with IOTLB. So it needs to be validated unconditionally otherwise we may try use 0 as log_base which may lead to pi

Re: [PATCH net] vhost: validate log when IOTLB is enabled

2018-03-29 Thread David Miller
From: "Michael S. Tsirkin" Date: Thu, 29 Mar 2018 15:48:22 +0300 > On Thu, Mar 29, 2018 at 04:00:04PM +0800, Jason Wang wrote: >> Vq log_base is the userspace address of bitmap which has nothing to do >> with IOTLB. So it needs to be validated unconditionally otherwise we >> may try use 0 as log_

Re: [PATCH net] vhost: validate log when IOTLB is enabled

2018-03-29 Thread Michael S. Tsirkin
On Thu, Mar 29, 2018 at 04:00:04PM +0800, Jason Wang wrote: > Vq log_base is the userspace address of bitmap which has nothing to do > with IOTLB. So it needs to be validated unconditionally otherwise we > may try use 0 as log_base which may lead to pin pages that will lead > unexpected result (e.g

Re: [PATCH net] vhost: validate log when IOTLB is enabled

2018-03-29 Thread Michael S. Tsirkin
On Thu, Mar 29, 2018 at 04:00:04PM +0800, Jason Wang wrote: > Vq log_base is the userspace address of bitmap which has nothing to do > with IOTLB. So it needs to be validated unconditionally otherwise we > may try use 0 as log_base which may lead to pin pages that will lead > unexpected result (e.g

[PATCH net] vhost: validate log when IOTLB is enabled

2018-03-29 Thread Jason Wang
Vq log_base is the userspace address of bitmap which has nothing to do with IOTLB. So it needs to be validated unconditionally otherwise we may try use 0 as log_base which may lead to pin pages that will lead unexpected result (e.g trigger BUG_ON() in set_bit_to_user()). Fixes: 6b1e6cc7855b0 ("vho