Re: [PATCH v12 03/26] ima: Define ima_namespace struct and start moving variables into it

From: Stefan Berger <stefanb@linux.ibm.com>
To: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-integrity@vger.kernel.org, zohar@linux.ibm.com,
	christian.brauner@ubuntu.com, containers@lists.linux.dev,
	dmitry.kasatkin@gmail.com, ebiederm@xmission.com,
	krzysztof.struczynski@huawei.com, roberto.sassu@huawei.com,
	mpeters@redhat.com, lhinds@redhat.com, lsturman@redhat.com,
	puiterwi@redhat.com, jejb@linux.ibm.com, jamjoom@us.ibm.com,
	linux-kernel@vger.kernel.org, paul@paul-moore.com,
	rgb@redhat.com, linux-security-module@vger.kernel.org,
	jmorris@namei.org, jpenumak@redhat.com,
	Christian Brauner <brauner@kernel.org>
Subject: Re: [PATCH v12 03/26] ima: Define ima_namespace struct and start moving variables into it
Date: Tue, 24 May 2022 12:18:28 -0400	[thread overview]
Message-ID: <8ba32888-32ad-cf92-49e6-15d432331bba@linux.ibm.com> (raw)
In-Reply-To: <20220521023351.GA9107@mail.hallyn.com>

On 5/20/22 22:33, Serge E. Hallyn wrote:

>>    * they make a queue.  The policy may be updated multiple times and this is the
>> @@ -985,16 +988,17 @@ int ima_check_policy(void)
>>    * Policy rules are never deleted so ima_policy_flag gets zeroed only once when
>>    * we switch from the default policy to user defined.
>>    */
>> -void ima_update_policy(void)
>> +void ima_update_policy(struct ima_namespace *ns)
>>   {
>> -	struct list_head *policy = &ima_policy_rules;
>> +	struct list_head *policy = &ns->ima_policy_rules;
>>   
>> -	list_splice_tail_init_rcu(&ima_temp_rules, policy, synchronize_rcu);
>> +	list_splice_tail_init_rcu(&ns->ima_temp_rules, policy,
>> +				  synchronize_rcu);
>>   
>> -	if (ima_rules != (struct list_head __rcu *)policy) {
>> -		ima_policy_flag = 0;
>> +	if (ns->ima_rules != (struct list_head __rcu *)policy) {
>> +		ns->ima_policy_flag = 0;
>>   
>> -		rcu_assign_pointer(ima_rules, policy);
>> +		rcu_assign_pointer(ns->ima_rules, policy);
>>   		/*
>>   		 * IMA architecture specific policy rules are specified
>>   		 * as strings and converted to an array of ima_entry_rules
>> @@ -1003,10 +1007,10 @@ void ima_update_policy(void)
>>   		 */
>>   		kfree(arch_policy_entry);
>>   	}
>> -	ima_update_policy_flags();
>> +	ima_update_policy_flags(ns);
>>   
>>   	/* Custom IMA policy has been loaded */
>> -	ima_process_queued_keys();
>> +	ima_process_queued_keys(ns);
>>   }
>>   

So this is a caller that may enter that function with ns != init_ima_ns 
and in that case that function should do nothing. So, also the WARN_ON() 
is not appropriate then.

    Stefan