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

From: Petr Machata
Date: Wed Jun 05 2024 - 06:41:03 EST



"Matthieu Baerts (NGI0)" <matttbe@xxxxxxxxxx> 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@xxxxxxxxxxxxxxx
> Acked-by: Geliang Tang <geliang@xxxxxxxxxx>
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
> ---
> 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.

> ip netns delete "${ns}" &> /dev/null
> if ! busywait $BUSYWAIT_TIMEOUT ip netns list \| grep -vq "^$ns$" &> /dev/null; then
> echo "Warn: Failed to remove namespace $ns"
> @@ -150,7 +151,7 @@ cleanup_ns()
>
> cleanup_all_ns()
> {
> - cleanup_ns $NS_LIST
> + cleanup_ns "${NS_LIST[@]}"
> }
>
> # setup netns with given names as prefix. e.g
> @@ -159,7 +160,7 @@ setup_ns()
> {
> local ns=""
> local ns_name=""
> - local ns_list=""
> + local ns_list=()
> local ns_exist=
> for ns_name in "$@"; do
> # Some test may setup/remove same netns multi times
> @@ -175,13 +176,13 @@ setup_ns()
>
> if ! ip netns add "$ns"; then
> echo "Failed to create namespace $ns_name"
> - cleanup_ns "$ns_list"
> + cleanup_ns "${ns_list[@]}"
> return $ksft_skip
> fi
> ip -n "$ns" link set lo up
> - ! $ns_exist && ns_list="$ns_list $ns"
> + ! $ns_exist && ns_list+=("$ns")
> done
> - NS_LIST="$NS_LIST $ns_list"
> + NS_LIST+=("${ns_list[@]}")
> }
>
> tc_rule_stats_get()