[Devel] [PATCH vz10 v2 1/6] selftests: net: run the fdb and bind tests in their own netns

[Konstantin Khorenko]

Eva, you have sent a v2 of the patchset.

Where is the changelog between v1 and v2?
What has changed in between?

--
Best regards,

Konstantin Khorenko,
Virtuozzo Linux Kernel Team

On 9/22/26 14:02, Eva Kurchatova wrote:
> Three tests share the initial namespace with the machine and fail on
> what is already in it.
> 
> fdb_notify and test_vxlan_fdb_changelink bring up a vxlan device on the
> default port 4789. Where the machine already has one there, and that
> one is metadata based, as the device open vswitch keeps is, the port
> cannot be shared and the test device is never created:
> 
>   # ip link add vxs type vxlan external dstport 4789
>   # ip link add name vx up type vxlan id 2000 dstport 4789
>   RTNETLINK answers: Address already in use
>   # ./test_vxlan_fdb_changelink.sh
>   Cannot find device "vx"
>   expected two remotes after link set	[FAIL]
> 
> Run both in a fresh namespace by re-executing them there, the way
> nft_audit.sh, nft_concat_range.sh and br_netfilter_queue.sh already do.
> 
> bind_wildcard binds 0.0.0.0 and expects to know which sockets exist.
> With 432 foreign sockets on 0.0.0.0 on the machine it failed 6 runs out
> of 10; unsharing a namespace in FIXTURE_SETUP took that to 0 out of 10.
> This is what commit a897e194c475 ("selftests: net: run reuseport in an
> isolated netns") does for the reuseport tests.
> 
> https://virtuozzo.atlassian.net/browse/VSTOR-139651
> Feature: fix selftests
> Signed-off-by: Eva Kurchatova <eva.kurchatova at virtuozzo.com>
> ---
>  tools/testing/selftests/net/bind_wildcard.c         | 13 +++++++++++++
>  tools/testing/selftests/net/fdb_notify.sh           |  7 +++++++
>  .../selftests/net/test_vxlan_fdb_changelink.sh      |  7 +++++++
>  3 files changed, 27 insertions(+)
> 
> diff --git a/tools/testing/selftests/net/bind_wildcard.c b/tools/testing/selftests/net/bind_wildcard.c
> index b7b54d646b93..5ebf21c97df1 100644
> --- a/tools/testing/selftests/net/bind_wildcard.c
> +++ b/tools/testing/selftests/net/bind_wildcard.c
> @@ -1,6 +1,10 @@
>  // SPDX-License-Identifier: GPL-2.0
>  /* Copyright Amazon.com Inc. or its affiliates. */
>  
> +#define _GNU_SOURCE
> +#include <sched.h>
> +
> +#include <stdlib.h>
>  #include <sys/socket.h>
>  #include <netinet/in.h>
>  
> @@ -716,6 +720,15 @@ static void setup_addr(FIXTURE_DATA(bind_wildcard) *self, int i,
>  
>  FIXTURE_SETUP(bind_wildcard)
>  {
> +	/* The port is picked by the kernel and the test then expects every
> +	 * conflict on it to be one it caused itself.  A socket the rest of
> +	 * the system holds on that port breaks that: a v6only bind to ::
> +	 * is given a port whose 0.0.0.0 counterpart is taken, and the
> +	 * binds that follow fail with EADDRINUSE the test does not expect.
> +	 */
> +	ASSERT_EQ(unshare(CLONE_NEWNET), 0);
> +	ASSERT_EQ(system("ip link set lo up"), 0);
> +
>  	setup_addr(self, 0, variant->family[0], variant->addr[0]);
>  	setup_addr(self, 1, variant->family[1], variant->addr[1]);
>  
> diff --git a/tools/testing/selftests/net/fdb_notify.sh b/tools/testing/selftests/net/fdb_notify.sh
> index c159230c9b62..4f65f6720b1b 100755
> --- a/tools/testing/selftests/net/fdb_notify.sh
> +++ b/tools/testing/selftests/net/fdb_notify.sh
> @@ -1,6 +1,13 @@
>  #!/bin/bash
>  # SPDX-License-Identifier: GPL-2.0
>  
> +# The test brings up a vxlan device on the default port, which fails where
> +# the host already has one, as a metadata-based device holding that port is
> +# not compatible with the one the test asks for:
> +#   RTNETLINK answers: Address already in use
> +# Run in a fresh network namespace, like the netfilter tests do.
> +[ "${1}" != "run" ] && { unshare -n "${0}" run; exit $?; }
> +
>  source lib.sh
>  
>  ALL_TESTS="
> diff --git a/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh b/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh
> index 2d442cdab11e..7319bbcc4fbc 100755
> --- a/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh
> +++ b/tools/testing/selftests/net/test_vxlan_fdb_changelink.sh
> @@ -3,6 +3,13 @@
>  
>  # Check FDB default-remote handling across "ip link set".
>  
> +# The test brings up a vxlan device on the default port, which fails where
> +# the host already has one, as a metadata-based device holding that port is
> +# not compatible with the one the test asks for:
> +#   RTNETLINK answers: Address already in use
> +# Run in a fresh network namespace, like the netfilter tests do.
> +[ "${1}" != "run" ] && { unshare -n "${0}" run; exit $?; }
> +
>  check_remotes()
>  {
>  	local what=$1; shift