Re: [PATCH 2/3] selftests/bpf: Migrate test_xdp_redirect.sh to xdp_do_redirect.c

[Martin KaFai Lau <martin.lau@xxxxxxxxx>]

On 1/3/25 2:10 AM, Bastien Curutchet (eBPF Foundation) wrote:
> +static int ping_setup(struct test_data *data)
> +{
> +	struct nstoken *nstoken = NULL;
> +	int i;
> +
> +	data->ns[0] = netns_new(NS0, false);
> +	if (!ASSERT_OK_PTR(data->ns[0], "create ns"))
> +		return -1;
> +
> +	for (i = 1; i < NS_NB; i++) {
> +		char ns_name[4] = {};
> +
> +		snprintf(ns_name, 4, "NS%d", i);
> +		data->ns[i] = netns_new(ns_name, false);
> +		if (!ASSERT_OK_PTR(data->ns[i], "create ns"))
> +			goto fail;
> +
> +		nstoken = open_netns(NS0);
> +		if (!ASSERT_OK_PTR(nstoken, "open NS0"))
> +			goto fail;
> +
> +		SYS(fail, "ip link add veth%d index %d%d%d type veth peer name veth0 netns %s",
> +		    i, i, i, i, ns_name);
> +		SYS(fail, "ip link set veth%d up", i);
> +		close_netns(nstoken);
> +
> +		nstoken = open_netns(ns_name);
> +		if (!ASSERT_OK_PTR(nstoken, "open ns"))
> +			goto fail;
> +
> +		SYS(fail, "ip addr add %s.%d/24 dev veth0", IPV4_NETWORK, i);
> +		SYS(fail, "ip link set veth0 up");
> +		close_netns(nstoken);

		nstoken = NULL;

Otherwise, the other "goto fail;" of this loop will close and free the already 
closed nstoken again.

Some of the other close_netns(nstoken) in this patch may have similar issue.

> +	}
> +
> +	return 0;
> +
> +fail:
> +	close_netns(nstoken);
> +	cleanup(data);
> +	return -1;
> +}