[PATCH -next] selftests/landlock: Fix selftest ptrace_test run fail

[Mickaël Salaün]

I tested with next-20221116 and all tests are OK. Could you share your 
kernel configuration with a link? What is the content of /proc/cmdline?

On 29/11/2022 02:42, limin wrote:
> I run test on Linux ubuntu2204 6.1.0-next-20221116
> 
> I did't use yama.
> 
> you can reproduce by this step:
> 
> cd kernel_src
> 
> cd tools/testing/selftests/landlock/
> make
> ./ptrace_test
> 
> 
> 
> 
> On 2022/11/29 3:44, Mickaël Salaün wrote:
>> This patch changes the test semantic and then cannot work on my test
>> environment. On which kernel did you run test? Do you use Yama or
>> something similar?
>>
>> On 28/11/2022 03:04, limin wrote:
>>> Tests PTRACE_ATTACH and PTRACE_MODE_READ on the parent,
>>> trace parent return -1 when child== 0
>>> How to reproduce warning:
>>> $ make -C tools/testing/selftests TARGETS=landlock run_tests
>>>
>>> Signed-off-by: limin <limin100 at huawei.com>
>>> ---
>>>    tools/testing/selftests/landlock/ptrace_test.c | 5 ++---
>>>    1 file changed, 2 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/tools/testing/selftests/landlock/ptrace_test.c
>>> b/tools/testing/selftests/landlock/ptrace_test.c
>>> index c28ef98ff3ac..88c4dc63eea0 100644
>>> --- a/tools/testing/selftests/landlock/ptrace_test.c
>>> +++ b/tools/testing/selftests/landlock/ptrace_test.c
>>> @@ -267,12 +267,11 @@ TEST_F(hierarchy, trace)
>>>            /* Tests PTRACE_ATTACH and PTRACE_MODE_READ on the parent. */
>>>            err_proc_read = test_ptrace_read(parent);
>>>            ret = ptrace(PTRACE_ATTACH, parent, NULL, 0);
>>> +        EXPECT_EQ(-1, ret);
>>> +        EXPECT_EQ(EPERM, errno);
>>>            if (variant->domain_child) {
>>> -            EXPECT_EQ(-1, ret);
>>> -            EXPECT_EQ(EPERM, errno);
>>>                EXPECT_EQ(EACCES, err_proc_read);
>>>            } else {
>>> -            EXPECT_EQ(0, ret);
>>>                EXPECT_EQ(0, err_proc_read);
>>>            }
>>>            if (ret == 0) {