selftests/bpf/xdp_redirect_multi: Limit the tests in netns

[ Upstream commit 8955c1a329873385775081e029d9a7c6aa9037e1 ]

As I want to test both DEVMAP and DEVMAP_HASH in XDP multicast redirect, I
limited DEVMAP max entries to a small value for performace. When the test
runs after amount of interface creating/deleting tests. The interface index
will exceed the map max entries and xdp_redirect_multi will error out with
"Get interfacesInterface index to large".

Fix this issue by limit the tests in netns and specify the ifindex when
creating interfaces.

Fixes: d23292476297 ("selftests/bpf: Add xdp_redirect_multi test")
Reported-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211027033553.962413-5-liuhangbin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/tools/testing/selftests/bpf/xdp_redirect_multi.c b/tools/testing/selftests/bpf/xdp_redirect_multi.c
index 3696a8f32c23..f5ffba341c17 100644
--- a/tools/testing/selftests/bpf/xdp_redirect_multi.c
+++ b/tools/testing/selftests/bpf/xdp_redirect_multi.c
@@ -129,7 +129,7 @@ int main(int argc, char **argv)
 		goto err_out;
 	}
 
-	printf("Get interfaces");
+	printf("Get interfaces:");
 	for (i = 0; i < MAX_IFACE_NUM && argv[optind + i]; i++) {
 		ifaces[i] = if_nametoindex(argv[optind + i]);
 		if (!ifaces[i])
@@ -139,7 +139,7 @@ int main(int argc, char **argv)
 			goto err_out;
 		}
 		if (ifaces[i] > MAX_INDEX_NUM) {
-			printf("Interface index to large\n");
+			printf(" interface index too large\n");
 			goto err_out;
 		}
 		printf(" %d", ifaces[i]);