selftests/net: convert vrf_strict_mode_test.sh to run it in unique namespace

Here is the test result after conversion.

]# ./vrf_strict_mode_test.sh

################################################################################
TEST SECTION: VRF strict_mode test on init network namespace
################################################################################

TEST: init: net.vrf.strict_mode is available [ OK ]

TEST: init: strict_mode=0 by default, 0 vrfs [ OK ]

...

TEST: init: check strict_mode=1 [ OK ]

TEST: testns-HvoZkB: check strict_mode=0 [ OK ]

Tests passed: 37
Tests failed: 0

Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: vrf_strict_mode_test: add support to select a test to run

Add a boilerplate test loop to run all tests in
vrf_strict_mode_test.sh. Add a -t flag that allows a selected test to
run. Remove the vrf_strict_mode_tests function which is now unused.

Signed-off-by: Jaehee Park <jhpark1013@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220429164658.GA656707@jaehee-ThinkPad-X1-Extreme
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftests/net: Use kselftest skip code for skipped tests

There are several test cases in the net directory are still using
exit 0 or exit 1 when they need to be skipped. Use kselftest
framework skip code instead so it can help us to distinguish the
return status.

Criterion to filter out what should be fixed in net directory:
grep -r "exit [01]" -B1 | grep -i skip

This change might cause some false-positives if people are running
these test scripts directly and only checking their return codes,
which will change from 0 to 4. However I think the impact should be
small as most of our scripts here are already using this skip code.
And there will be no such issue if running them with the kselftest
framework.

Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20210823085854.40216-1-po-hsu.lin@canonical.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

vrf: Handle CONFIG_SYSCTL not set

Randy reported compile failure when CONFIG_SYSCTL is not set/enabled:

ERROR: modpost: "sysctl_vals" [drivers/net/vrf.ko] undefined!

Fix by splitting out the sysctl init and cleanup into helpers that
can be set to do nothing when CONFIG_SYSCTL is disabled. In addition,
move vrf_strict_mode and vrf_strict_mode_change to above
vrf_shared_table_handler (code move only) and wrap all of it
in the ifdef CONFIG_SYSCTL.

Update the strict mode tests to check for the existence of the
/proc/sys entry.

Fixes: 33306f1aaf82 ("vrf: add sysctl parameter for strict mode")
Cc: Andrea Mayer <andrea.mayer@uniroma2.it>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David Ahern <dsahern@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: add selftest for the VRF strict mode

The new strict mode functionality is tested in different configurations and
on different network namespaces.

Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: David S. Miller <davem@davemloft.net>