Re: [LTP] [PATCH V4] readlink03: fix return value for the syscall readlink()

[Wanlong G. <gao...@cn...>]

On 03/15/2012 01:22 PM, Caspar Zhang wrote:

> On 03/15/2012 12:32 PM, Wanlong Gao wrote:
>> Since commit http://git.kernel.org/linus/65cfc672
>> which added O_PATH support to the *at() calls,
>> the error return for readlink/readlinkat
>> for the empty pathname has switched from
>> ENOENT to EINVAL. And this patch merged to linux v2.6.39,
>> So LTP commit https://github.com/linux-test-project/ltp/commit/0cc7514
>> fix this with the kernel version v2.6.39 compared.
>>
>> But recently, commit http://git.kernel.org/linus/1fa1e7f6
>> which ensure we return ENOENT for the empty pathname
>> for normal lookups.
>>
>> Now, the patch whitch switch the return value back again
>> is already queued for 3.0 and 3.1 stable release.
>>
>> So, if the return value is EINVAL for empty pathname,
>> it may be a kernel bug, so we needn't to check the kernel
>> version but return the "kernel bug" warning  to LTP the users.
>>
>> Signed-off-by: Wanlong Gao <gao...@cn...>
>> Acked-by: Jan Stancek <jst...@re...>
> 
> Acked-by: Caspar Zhang <ca...@ca...>


pushed, thanks for your review Caspar.

Regards,
Wanlong Gao

> 
>> ---
>>  testcases/kernel/syscalls/readlink/readlink03.c |    9 ++++-----
>>  1 file changed, 4 insertions(+), 5 deletions(-)
>>
>> diff --git a/testcases/kernel/syscalls/readlink/readlink03.c b/testcases/kernel/syscalls/readlink/readlink03.c
>> index 370bf7d..5ae8513 100644
>> --- a/testcases/kernel/syscalls/readlink/readlink03.c
>> +++ b/testcases/kernel/syscalls/readlink/readlink03.c
>> @@ -173,11 +173,6 @@ int main(int ac, char **av)
>>  				buf_size = sizeof(buffer);
>>  			}
>>  
>> -			if (strncmp(test_desc, "Symlink Pathname is empty", 25) == 0) {
>> -				if ((tst_kvercmp(2, 6, 39)) >= 0)
>> -					Test_cases[i].exp_errno = EINVAL;
>> -			}
>> -
>>  			/*
>>  			 * Call readlink(2) to test different test conditions.
>>  			 * verify that it fails with -1 return value and sets
>> @@ -204,6 +199,10 @@ int main(int ac, char **av)
>>  					 "errno=%d, expected errno=%d",
>>  					 test_desc, TEST_ERRNO,
>>  					 Test_cases[i].exp_errno);
>> +				if ((strncmp(test_desc, "Symlink Pathname is empty", 25) == 0) &&
>> +				     TEST_ERRNO == EINVAL)
>> +					tst_resm(TWARN, "It may be a Kernel Bug, see the patch:"
>> +						 "http://git.kernel.org/linus/1fa1e7f6");
>>  			}
>>  		}
>>  	}
> 
>