selftests: netfilter: missing error check when setting up veth interface

BugLink: https://bugs.launchpad.net/bugs/1838824
[ Upstream commit 82ce6eb1dd13fd12e449b2ee2c2ec051e6f52c43 ]

A test for the basic NAT functionality uses ip command which needs veth
device. There is a condition where the kernel support for veth is not
compiled into the kernel and the test script breaks. This patch contains
code for reasonable error display and correct code exit.

Signed-off-by: Jeffrin Jose T <jeffrin@rajagiritech.edu.in>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/tools/testing/selftests/netfilter/nft_nat.sh b/tools/testing/selftests/netfilter/nft_nat.sh
index 8ec76681605cca08f8cad14720ada2986d74f76c..f25f72a75cf3dbb6204bf78bea1a7cd89d348b9c 100755 (executable)
--- a/tools/testing/selftests/netfilter/nft_nat.sh
+++ b/tools/testing/selftests/netfilter/nft_nat.sh
@@ -23,7 +23,11 @@ ip netns add ns0
 ip netns add ns1
 ip netns add ns2
 
-ip link add veth0 netns ns0 type veth peer name eth0 netns ns1
+ip link add veth0 netns ns0 type veth peer name eth0 netns ns1 > /dev/null 2>&1
+if [ $? -ne 0 ];then
+    echo "SKIP: No virtual ethernet pair device support in kernel"
+    exit $ksft_skip
+fi
 ip link add veth1 netns ns0 type veth peer name eth0 netns ns2
 
 ip -net ns0 link set lo up