Re: [PATCH net 2/3] selftests: net: lib: avoid error removing empty netns name

[Matthieu Baerts <matttbe@kernel.org>]

On 05/06/2024 16:30, Petr Machata wrote:
> 
> Matthieu Baerts <matttbe@kernel.org> writes:
> 
>> Hi Petr,
>>
>> Thank you for the review!
>>
>> On 05/06/2024 12:38, Petr Machata wrote:
>>>
>>> "Matthieu Baerts (NGI0)" <matttbe@kernel.org> writes:
>>>
>>>> If there is an error to create the first netns with 'setup_ns()',
>>>> 'cleanup_ns()' will be called with an empty string as first parameter.
>>>>
>>>> The consequences is that 'cleanup_ns()' will try to delete an invalid
>>>> netns, and wait 20 seconds if the netns list is empty.
>>>>
>>>> Instead of just checking if the name is not empty, convert the string
>>>> separated by spaces to an array. Manipulating the array is cleaner, and
>>>> calling 'cleanup_ns()' with an empty array will be a no-op.
>>>>
>>>> Fixes: 25ae948b4478 ("selftests/net: add lib.sh")
>>>> Cc: stable@vger.kernel.org
>>>> Acked-by: Geliang Tang <geliang@kernel.org>
>>>> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
>>>> ---
>>>>  tools/testing/selftests/net/lib.sh | 13 +++++++------
>>>>  1 file changed, 7 insertions(+), 6 deletions(-)
>>>>
>>>> diff --git a/tools/testing/selftests/net/lib.sh b/tools/testing/selftests/net/lib.sh
>>>> index a422e10d3d3a..e2f51102d7e1 100644
>>>> --- a/tools/testing/selftests/net/lib.sh
>>>> +++ b/tools/testing/selftests/net/lib.sh
>>>> @@ -15,7 +15,7 @@ ksft_xfail=2
>>>>  ksft_skip=4
>>>>  
>>>>  # namespace list created by setup_ns
>>>> -NS_LIST=""
>>>> +NS_LIST=()
>>>>  
>>>>  ##############################################################################
>>>>  # Helpers
>>>> @@ -137,6 +137,7 @@ cleanup_ns()
>>>>  	fi
>>>>  
>>>>  	for ns in "$@"; do
>>>> +		[ -z "${ns}" ] && continue
>>>
>>> I think this is now irrelevant though? Now cleanup_ns() will be called
>>> with no arguments for an empty NS list, so the loop does not even kick in.
>>
>> If you don't mind, I think it is "safer" to keep it: some selftests are
>> using 'cleanup_ns()' directly, not via 'cleanup_all_ns()', e.g.
>> netns-name.sh, cmsg-*.sh, fib-*.sh, etc. which can call it with the
>> variables not set if 'setup_ns' failed during the init phase.
>>
>> For the moment, all these selftests are calling 'cleanup_ns()' with
>> parameters added without double quotes: so it is fine. Until someone
>> changes that to please shellcheck, like we did on our side with MPTCP
>> selftests. So this line will be useful soon when we will publish the
>> rest of our patches to use 'lib.sh' [1] :)
> 
> All right.
> 
> Reviewed-by: Petr Machata <petrm@nvidia.com>

Thank you!

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.