Re: [LTP] [PATCH] sysctl03: sysctl returns EACCES after 2.6.33-rc1

Shi Weihua
2010-03-04T08:38:19Z

at 2010-2-25 9:18, Garrett Cooper wrote:
> On Mon, Feb 22, 2010 at 5:48 PM, Shi Weihua <shiwh@cn.fujitsu.com> wrote:
>> at 2010-2-22 15:44, Garrett Cooper wrote:
>>> Ok.. one last thing.
>>>
>>> On Sun, Feb 21, 2010 at 11:15 PM, Shi Weihua <shiwh@cn.fujitsu.com> wrote:
>>>> at 2010-2-18 12:25, Rishikesh K Rajak wrote:
>>>>> On Wed, Feb 17, 2010 at 09:10:48AM -0800, Garrett Cooper wrote:
>>>>>> On Wed, Feb 17, 2010 at 12:01 AM, Rishikesh <risrajak@linux.vnet.ibm.com> wrote:
>>>>>>> Hi Shi,
>>>>>>>
>>>>>>> Thanks for your patch, still i am finding time to look into your patch.
>>>>>>> Will reply you soon.
>>>>>>>
>>>>>>> http://marc.info/?l=ltp-list&m=126502355614857&w=2
>>>>>>
>>>>>> I looked at the patch finally.
>>>>>
>>>>> Thanks garret.
>>>>>>
>>>>>> Please use TTERRNO instead of strerror(...) for the reported value.
>>>>>> There's no reason why you should use strerror(...) there as that's
>>>>>> already done with tst_res(3).
>>>>>
>>>>> Shi, can you please incorporate changes which garret has suggested and
>>>>> resend the patch again to ltp-list@ .
>>>>
>>>> Ok, i recreated the patch based on garret's suggestion.
>>>>
>>>> Signed-off-by: Shi Weihua <shiwh@cn.fujitsu.com>
>>>> ---
>>>> --- testcases/kernel/syscalls/sysctl/sysctl03.c.orig 2010-02-22 14:38:26.000000000 -0500
>>>> +++ testcases/kernel/syscalls/sysctl/sysctl03.c 2010-02-22 15:08:03.000000000 -0500
>>>> @@ -22,15 +22,18 @@
>>>> * sysctl03.c
>>>> *
>>>> * DESCRIPTION
>>>> - * Testcase to check that sysctl(2) sets errno to EPERM correctly.
>>>> + * Testcase to check that sysctl(2) sets errno to EPERM or EACCES
>>>> + * correctly. But it will return EACCES on kernels that are 2.6.33-rc1
>>>> + * and higher.
>>>> *
>>>> * ALGORITHM
>>>> * a. Call sysctl(2) as a root user, and attempt to write data
>>>> * to the kernel_table[]. Since the table does not have write
>>>> - * permissions even for the root, it should fail EPERM.
>>>> + * permissions even for the root, it should fail EPERM or EACCES.
>>>> * b. Call sysctl(2) as a non-root user, and attempt to write data
>>>> * to the kernel_table[]. Since the table does not have write
>>>> - * permission for the regular user, it should fail with EPERM.
>>>> + * permission for the regular user, it should fail with EPERM
>>>> + * or EACCES.
>>>> *
>>>> * USAGE: <for command-line>
>>>> * sysctl03 [-c n] [-e] [-i n] [-I x] [-P x] [-t]
>>>> @@ -43,6 +46,7 @@
>>>> *
>>>> * HISTORY
>>>> * 07/2001 Ported by Wayne Boyer
>>>> + * 02/2010 Updated by shiwh@cn.fujitsu.com
>>>> *
>>>> * RESTRICTIONS
>>>> * Test must be run as root.
>>>> @@ -82,6 +86,7 @@ int main(int ac, char **av)
>>>> {
>>>> int lc;
>>>> char *msg;
>>>> + int exp_eno;
>>>>
>>>> char osname[OSNAMESZ];
>>>> int osnamelth, status;
>>>> @@ -96,6 +101,13 @@ int main(int ac, char **av)
>>>>
>>>> setup();
>>>>
>>>> + if ((tst_kvercmp(2, 6, 32)) <= 0){
>>>> + exp_eno = EPERM;
>>>> + } else {
>>>> + exp_eno = EACCES;
>>>> + exp_enos[0] = EACCES;
>>>> + }
>>>> +
>>>> TEST_EXP_ENOS(exp_enos);
>>>>
>>>> /* check looping state if -i option is given */
>>>> @@ -114,13 +126,10 @@ int main(int ac, char **av)
>>>> } else {
>>>> TEST_ERROR_LOG(TEST_ERRNO);
>>>>
>>>> - if (TEST_ERRNO != EPERM) {
>>>> - tst_resm(TFAIL,
>>>> - "Expected EPERM (%d), got %d: %s",
>>>> - EPERM, TEST_ERRNO,
>>>> - strerror(TEST_ERRNO));
>>>> + if (TEST_ERRNO != exp_eno) {
>>>> + tst_resm(TFAIL|TTERRNO, "Got unxpected error");
>>>> } else {
>>>> - tst_resm(TPASS, "Got expected EPERM error");
>>>> + tst_resm(TPASS|TTERRNO, "Got expected error");
>>>> }
>>>> }
>>>>
>>>> @@ -147,12 +156,10 @@ int main(int ac, char **av)
>>>> } else {
>>>> TEST_ERROR_LOG(TEST_ERRNO);
>>>>
>>>> - if (TEST_ERRNO != EPERM) {
>>>> - tst_resm(TFAIL, "Expected EPERM, got "
>>>> - "%d", TEST_ERRNO);
>>>> + if (TEST_ERRNO != exp_eno) {
>>>
>>> Why can't this be exp_enos[0] ?
>>
>> Using exp_enos[0] is ok. pls check the latest patch in this mail.
>>
>>>
>>>> + tst_resm(TFAIL|TTERRNO, "Got unxpected error");
>>>
>>> Typo.
>>>
>>>> } else {
>>>> - tst_resm(TPASS, "Got expected EPERM "
>>>> - "error");
>>>> + tst_resm(TPASS|TTERRNO, "Got expected error");
>>>> }
>>>> }
>>>>
>>>>
>>>> Thank you.
>>>> - Shi Weihua
>>>
>>> It always helps to understand what's expected vs unexpected
>>> without having to look at the source code. Could you please revise the
>>> tst_resm format strings to be something like the following?
>>>
>>> tst_resm (TPASS | TERRNO, "Got expected error (errno = %d, ret_code =
>>> %d", exp_errno_blah, exp_ret_code_blah);
>>>
>>> OR:
>>>
>>> tst_resm (TPASS | TERRNO, "Got unexpected error (expected errno = %d,
>>> ret_code = %d - got errno = %d, ret_code = %d", exp_errno_blah,
>>> exp_ret_code_blah, errno_blah, ret_code_blah);
>>
>> ret_code has not been defined in sysctl03.c, i think it's unnecessarily to
>> import a new parameter. maybe, we can use your macro when it created. ;-)
>>
>> --- testcases/kernel/syscalls/sysctl/sysctl03.c.orig 2010-02-22 14:38:26.000000000 -0500
>> +++ testcases/kernel/syscalls/sysctl/sysctl03.c 2010-02-23 09:35:20.000000000 -0500
>> @@ -22,15 +22,18 @@
>> * sysctl03.c
>> *
>> * DESCRIPTION
>> - * Testcase to check that sysctl(2) sets errno to EPERM correctly.
>> + * Testcase to check that sysctl(2) sets errno to EPERM or EACCES
>> + * correctly. But it will return EACCES on kernels that are 2.6.33-rc1
>> + * and higher.
>> *
>> * ALGORITHM
>> * a. Call sysctl(2) as a root user, and attempt to write data
>> * to the kernel_table[]. Since the table does not have write
>> - * permissions even for the root, it should fail EPERM.
>> + * permissions even for the root, it should fail EPERM or EACCES.
>> * b. Call sysctl(2) as a non-root user, and attempt to write data
>> * to the kernel_table[]. Since the table does not have write
>> - * permission for the regular user, it should fail with EPERM.
>> + * permission for the regular user, it should fail with EPERM
>> + * or EACCES.
>> *
>> * USAGE: <for command-line>
>> * sysctl03 [-c n] [-e] [-i n] [-I x] [-P x] [-t]
>> @@ -43,6 +46,7 @@
>> *
>> * HISTORY
>> * 07/2001 Ported by Wayne Boyer
>> + * 02/2010 Updated by shiwh@cn.fujitsu.com
>> *
>> * RESTRICTIONS
>> * Test must be run as root.
>> @@ -96,6 +100,12 @@ int main(int ac, char **av)
>>
>> setup();
>>
>> + if ((tst_kvercmp(2, 6, 32)) <= 0){
>> + exp_enos[0] = EPERM;
>> + } else {
>> + exp_enos[0] = EACCES;
>> + }
>> +
>> TEST_EXP_ENOS(exp_enos);
>>
>> /* check looping state if -i option is given */
>> @@ -114,13 +124,12 @@ int main(int ac, char **av)
>> } else {
>> TEST_ERROR_LOG(TEST_ERRNO);
>>
>> - if (TEST_ERRNO != EPERM) {
>> - tst_resm(TFAIL,
>> - "Expected EPERM (%d), got %d: %s",
>> - EPERM, TEST_ERRNO,
>> - strerror(TEST_ERRNO));
>> + if (TEST_ERRNO != exp_enos[0]) {
>> + tst_resm(TFAIL|TTERRNO, "Got unxpected error "
>> + "(expected error = %d)", exp_enos[0]);
>> } else {
>> - tst_resm(TPASS, "Got expected EPERM error");
>> + tst_resm(TPASS|TTERRNO, "Got expected error "
>> + "(errno = %d)", exp_enos[0]);
>> }
>> }
>>
>> @@ -147,12 +156,12 @@ int main(int ac, char **av)
>> } else {
>> TEST_ERROR_LOG(TEST_ERRNO);
>>
>> - if (TEST_ERRNO != EPERM) {
>> - tst_resm(TFAIL, "Expected EPERM, got "
>> - "%d", TEST_ERRNO);
>> + if (TEST_ERRNO != exp_enos[0]) {
>> + tst_resm(TFAIL|TTERRNO, "Got unxpected error "
>> + "(expected error = %d)", exp_enos[0]);
>> } else {
>> - tst_resm(TPASS, "Got expected EPERM "
>> - "error");
>> + tst_resm(TPASS|TTERRNO, "Got expected error "
>> + "(errno = %d)", exp_enos[0]);
>> }
>> }
>
> Ok, before I go and commit this, there are two things I need to know
> (because trusty Google didn't turn up any results for this behavioral
> change):
>
> 1. The change is legitimate.
> 2. The documentation is up to date, or a bug has been filed for the
> documentation change.
>
> If you can provide these two things, I'll commit the change.

At this time of day, I can not find any documentation about EPERM->EACCES.
But, i caught the kernel commit which caused ltp bug:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=26a7034b40ba80f82f64fa251a2cbf49f9971c6a
Maybe it can help you to judge.

>
> Thanks,
> -Garrett