From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] vhost: validate log when IOTLB is enabled
Date: Thu, 29 Mar 2018 16:23:12 -0400 (EDT)
Message-ID: <20180329.162312.1243047104828828329.davem@davemloft.net>
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        <20180329154803-mutt-send-email-mst@kernel.org>
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From: "Michael S. Tsirkin" <mst@redhat.com>
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_base which may lead to pin pages that will lead
>> unexpected result (e.g trigger BUG_ON() in set_bit_to_user()).
>> 
>> Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API")
>> Reported-by: syzbot+6304bf97ef436580fede@syzkaller.appspotmail.com
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
> 
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
> 
> stable material I guess.

Applied and queued up for -stable.