DPDK patches and discussions
 help / color / mirror / Atom feed
From: Linhaifeng <haifeng.lin@huawei.com>
To: "Qiu, Michael" <michael.qiu@intel.com>,
	"Xie, Huawei" <huawei.xie@intel.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH] vhost: Fix Segmentation fault of NULL address
Date: Thu, 26 Mar 2015 16:29:04 +0800	[thread overview]
Message-ID: <5513C350.9090609@huawei.com> (raw)
In-Reply-To: <533710CFB86FA344BFBF2D6802E60286D18871@SHSMSX101.ccr.corp.intel.com>



On 2015/3/26 15:58, Qiu, Michael wrote:
> On 3/26/2015 3:52 PM, Xie, Huawei wrote:
>> On 3/26/2015 3:05 PM, Qiu, Michael wrote:
>>> Function gpa_to_vva() could return zero, while this will lead
>>> a Segmentation fault.
>>>
>>> This patch is to fix this issue.
>>>
>>> Signed-off-by: Michael Qiu <michael.qiu@intel.com>
>>> ---
>>>  lib/librte_vhost/vhost_rxtx.c | 3 +++
>>>  1 file changed, 3 insertions(+)
>>>
>>> diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
>>> index 535c7a1..23c8acb 100644
>>> --- a/lib/librte_vhost/vhost_rxtx.c
>>> +++ b/lib/librte_vhost/vhost_rxtx.c
>>> @@ -587,6 +587,9 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id,
>>>  
>>>  		/* Buffer address translation. */
>>>  		vb_addr = gpa_to_vva(dev, desc->addr);
>>> +		if (!vb_addr)
>>> +			return entry_success;
>>> +
>> Firstly we should add check for all gpa_to_vva translation, and do
>> reporting and cleanup on error. We should avoid the case that some buggy
>> or malicious guest virtio driver gives us an invalid GPA(for example,
>> GPA for some MMIO space) and crash our vhost process.
> 
> Yes, agree, I will do this for next version.
> 
>> As we discuss, you meet segfault here, but our virtio PMD shouldn't give
>> us the GPA that has no translation, so we should root cause first and
> 
> Yes, root cause is very important, but it will spend lots time, and I
> think we could be possible to apply this first(All check version).
> 

How to deal with invalid address but not NULL?

> Thanks,
> Michael
>> fix the problem, and then submit the patch checking all gpa_to_vva
>> translation.
>>
>> -Huawei
>>>  		/* Prefetch buffer address. */
>>>  		rte_prefetch0((void *)(uintptr_t)vb_addr);
>>>  
>>
> 
> 
> 

  reply	other threads:[~2015-03-26  8:29 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-26  7:04 Michael Qiu
2015-03-26  7:52 ` Xie, Huawei
2015-03-26  7:58   ` Qiu, Michael
2015-03-26  8:29     ` Linhaifeng [this message]
2015-03-27  8:45       ` Qiu, Michael

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5513C350.9090609@huawei.com \
    --to=haifeng.lin@huawei.com \
    --cc=dev@dpdk.org \
    --cc=huawei.xie@intel.com \
    --cc=michael.qiu@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).