Re: Network hang after c3f1010b30f7fc611139cfb702a8685741aa6827 with CIPSO & Smack

[David Ahern <dsa@cumulusnetworks.com>]

On 7/6/16 10:24 AM, Casey Schaufler wrote:
> On 7/6/2016 9:28 AM, David Ahern wrote:
>> On 7/5/16 6:31 PM, Casey Schaufler wrote:
>>> On 7/5/2016 5:49 PM, David Ahern wrote:
>>>> On 7/5/16 5:38 PM, Casey Schaufler wrote:
>>>>> I have encountered a system hang with my Smack
>>>>> networking tests that bisects to the change below.
>>>>> I can't say that I have any idea why the change
>>>>> would impact the Smack processing, but there appears
>>>>> to be some serious packet processing going on. The
>>>>> Smack code is using CIPSO on the loopback interface.
>>>>> The test is supposed to verify that labels can be
>>>>> set on the packets using CIPSO. Unlabeled packets
>>>>> do not appear to be impacted. I do not know if SELinux
>>>>> is affected, and if not, why not. Smack and SELinux
>>>>> use CIPSO differently.
>>>>
>>>> What are the commands to repeat the test?
>>>>
>>> There is a tar file attached with the tests.
>>> Put the etc/smack/user file into /etc/smack/user.
>>> In the tools-2012 directory run make to build
>>> the tools. The test in question is called
>>> testnetworking.sh and needs to be run as root.
>>> You will need to configure Smack in the kernel,
>>> of course.
>>>
>>
>> I understand Paul's point and glad to see the changes are not causing issues with his SELinux testing.
>>
>> I have tried to reproduce the lockup you are seeing but not successful. I am using a jessie based VM with latest net-next kernel.
>>
>> root@kenny-jessie3:~/smack/tools-2012# zcat /proc/config.gz | grep SMACK
>> CONFIG_SECURITY_SMACK=y
>> CONFIG_SECURITY_SMACK_BRINGUP=y
>> CONFIG_SECURITY_SMACK_NETFILTER=y
>> # CONFIG_DEFAULT_SECURITY_SMACK is not set
>
> CONFIG_DEFAULT_SECURITY_SMACK needs to be set.

ok. That caused more interesting output but still no hang after all of 
the snap-crackle-and-pops.