[CRIU] [PATCHv6 5/5] dump: don't dump if children's uids are not equal to client's uid

[Ruslan Kuprieiev]

On 09/12/2013 02:36 PM, Pavel Emelyanov wrote:
> On 09/12/2013 01:00 AM, Ruslan Kuprieiev wrote:
>> Signed-off-by: Ruslan Kuprieiev <kupruser at gmail.com>
>>
>
>> @@ -773,6 +774,23 @@ static int parse_children(pid_t pid, pid_t **_c, int *_n)
>>   				goto err;
>>   			ch = tmp;
>>   			ch[nr - 1] = atoi(tok);
>> +
>> +			/*
>> +			 * Don't dump at all, if client's uid is not equal
>> +			 * to child's uid, unless client is root.
>> +			 */
>> +			if (cr_service_client != NULL) {
>> +				struct proc_status_creds cr;
>> +				if (parse_pid_status(ch[nr-1], &cr) == -1)
> I don't quite like that we parse the status twice (the 2nd one in dump_task_creds).
> Do the following -- call the parse_pid_status() early in dump_one_task before doing
> anything with the task, then check the uids and pass this structure into dump_creds.

By the way, isn't it wrong to check uids _after_ freezing task? I mean, 
it does work fast, but some indecent user(even non-root), can hold any! 
task freezed forever, by simply asking criu to dump it. But i do 
understand, that if we will not freeze task, our information about 
children could be incomplete.

>
>> +					goto err;
>> +
>> +				if (cr.uids[0] != cr_service_client->uid &&
>> +				    cr_service_client->uid != 0) {
>> +					pr_perror("Child's uid != client's");
>> +					goto err;
>> +				}
>> +			}
>> +
>>   			nr++;
>>   			tok = strtok(NULL, " \n");
>>   		}
>>