Hi,
I tested your patch.
I confirmed that XSM/ACM run normally.
Thank you for your help.
The result is put as follows.
#xm create vm1.conf <---- create domain1
Using config file "./vm1.conf".
#xm list --label
Name ID Mem VCPUs State Time(s) Label
vm1 3 128 1 r----- 1.0 ACM:example.client_v1:dom_HomeBanking
Domain-0 0 743 2 r----- 0.0 ACM:example.client_v1:dom_SystemManagement
#xm create vm2.conf <---- create domain2
Using config file "./vm2.conf".
Internal error: Domain in conflict set with running domain?.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#xm list --label
Name ID Mem VCPUs State Time(s) Label
vm1 3 128 1 r----- 1.0 ACM:example.client_v1:dom_HomeBanking
Domain-0 0 743 2 r----- 0.0 ACM:example.client_v1:dom_SystemManagement
Chinese Wall looks good and "system boot" did not appen.
Syunsuke HAYASHI.
> On Thu, 2007-09-27 at 16:12 -0400, Stefan Berger wrote:
>> "Coker, George" <gscoker@xxxxxxxxxxxxxx> wrote on 09/27/2007 03:35:14
>> PM:
>>
>>> This patch is correct for XSM. The patch creates clean
>>> acm_domain_create and acm_domain_destroy operations.
>>>
>>> In 15661 the logic under which acm_domain_destroy is called is
>> slightly
>>> different than under XSM. In 15661, acm_domain_destroy is called
>> only
>>> if the mask INIT_acm is set. INIT_acm is set only on successful
>> return
>>> from acm_domain_create. When acm_domain_create fails, the mask is
>> not
>>> set and acm_domain_destroy is not called. I do not know if this
>>> resulted in a leak in 15661 due to incomplete cleanup.
>> So the roll-back call that was necessary before is not necessary
>> anymore?
>>
>
> Yes, because on fail, acm_domain_create will always return
> ACM_ACCESS_DENIED which will cause domain_create to goto fail on return
> from xsm_domain_create. At fail, free_domain is called. free_domain
> calls xsm_free_security_domain which calls acm_domain_destroy.
>
> acm_domain_destroy calls the acm_primary_ops->domain_destroy followed by
> the acm_secondary_ops->domain_destroy. acm_domain_destroy ends with
> acm_free_domain_ssid. acm_domain_destroy already contains all of the
> rollback code that is replicated in acm_domain_create.
>
>> static inline int acm_domain_create(struct domain *d, ssidref_t
>> ssidref)
>> {
>> void *subject_ssid = current->domain->ssid;
>> domid_t domid = d->domain_id;
>> int rc;
>>
>> read_lock(&acm_bin_pol_rwlock);
>> /*
>> To be called when a domain is created; returns '0' if the
>> domain is allowed to be created, != '0' if not.
>> */
>> rc = acm_init_domain_ssid(d, ssidref);
>> if (rc != ACM_OK)
>> goto error_out;
>>
>> if ((acm_primary_ops->domain_create != NULL) &&
>> acm_primary_ops->domain_create(subject_ssid, ssidref, domid)) {
>> rc = ACM_ACCESS_DENIED;
>> } else if ((acm_secondary_ops->domain_create != NULL) &&
>> acm_secondary_ops->domain_create(subject_ssid, ssidref,
>> domid)) {
>> /* roll-back primary */
>> if (acm_primary_ops->domain_destroy != NULL)
>> acm_primary_ops->domain_destroy(d->ssid, d);
>> rc = ACM_ACCESS_DENIED;
>> }
>>
>> if ( rc == ACM_OK )
>> {
>> acm_domain_ssid_onto_list(d->ssid);
>> } else {
>> acm_free_domain_ssid(d->ssid);
>> }
>>
>> error_out:
>> read_unlock(&acm_bin_pol_rwlock);
>> return rc;
>> }
>>
>>
>> The acm_primary_ops->domain_create() establishes state (see
>> chwall_domain_create() in acm_chinesewall_hooks.c ) that if the
>> secondary operation fails needs to be undone. That's what the
>> acm_primary_ops->domain_destroy() did, but you intend to remove it?! I
>> have my doubts that this is correct.
>>
> Yes I am removing the rollback from acm_domain_create because it is
> already duplicated in acm_domain_destroy. acm_domain_destroy is always
> now called on fail under XSM. In 15661, acm_domain_destroy was not
> always called.
>
>> Which NULL pointer is the code running into and where?
>
> The NULL pointer was created in acm_free_domain_ssid and dereferenced in
> the fail code path in the call to xsm_free_security_domain in
> free_domain.
>
>> Stefan
>>
>>
>>> George
>>>
>>>
>>> On Thu, 2007-09-27 at 14:35 -0400, Stefan Berger wrote:
>>>> xense-devel-bounces@xxxxxxxxxxxxxxxxxxx wrote on 09/27/2007
>> 12:43:35
>>>> PM:
>>>>
>>>>> The attached patch fixes a null dereference bug in XSM:ACM.
>>>> As I read this in response to recent error reports - I wonder why
>> CS
>>>> 15661 does not expose this error whereas afterwards this error
>> occurs.
>>>> Are you sure this is the right solution? Was something changed in
>> this
>>>> area of the code between 'before XSM' and afterwards?
>>>>
>>>> Stefan
>>>>
>>>>
>>>>
>>>>> Signed-off-by: George Coker <gscoker@xxxxxxxxxxxxxx>
>>>>> [attachment "acm-xsm-null_bug-092707-xen-unstable-15880.diff"
>>>>> deleted by Stefan Berger/Watson/IBM]
>>>>> _______________________________________________
>>>>> Xense-devel mailing list
>>>>> Xense-devel@xxxxxxxxxxxxxxxxxxx
>>>>> http://lists.xensource.com/xense-devel
>>>> _______________________________________________
>>>> Xen-devel mailing list
>>>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>>>> http://lists.xensource.com/xen-devel
>>> --
>>> George S. Coker, II <gscoker@xxxxxxxxxxxxxx> 443-479-6944
>> _______________________________________________
>> Xense-devel mailing list
>> Xense-devel@xxxxxxxxxxxxxxxxxxx
>> http://lists.xensource.com/xense-devel
--
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富士通株式会社 新横浜TECHビル A館6F
サーバシステム事業本部 Linux技術開発統括部
Name : Syunsuke HAYASHI (林 俊介)
TEL : 7124-3846(内線) 045-473-9478(外線)
E-mail : syunsuke@xxxxxxxxxxxxxx
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