[LTP] [PATCH v2] netns/netns_helper.sh: Fix failure when testing ipv6 in netns

[Xiao Yang <yangx.jy@cn.fujitsu.com>]

Hi Alexey,

Could you help me review the v2 patch?
Thanks a lot. :-)

Thanks,
Xiao Yang
On 2017/12/21 11:22, xiao yang wrote:
> When testing ipv6 in network namespace, we got the following
> error on some distros(e.g. RHEL7.5Alpha):
> ----------------------------------------------------------------------------------
> connect: Cannot assign requested address
> netns_comm_ns_exec_ipv6_netlink 1 TFAIL: configuration and communication over veth0
> connect: Cannot assign requested address
> netns_comm_ns_exec_ipv6_netlink 2 TFAIL: configuration and communication over veth1
> -----------------------------------------------------------------------------------
>
> On a kernel with commits 35e015e1f577 and a2d3f3e33853, the global
> 'accept_dad' flag is taken into account and set to 1 by default.
> If global flag is non-zero, DAD will be enabled and trigger the
> failure on a given interface.  I think it should not be considered
> as a bug, and try to fix it by setting all.accept_dad to 0 manually.
>
> The default value of all.accept_dad has been set to 0 in kernel:
> '094009531612("ipv6: set all.accept_dad to 0 by default")'
>
> Signed-off-by: xiao yang <yangx.jy@cn.fujitsu.com>
> ---
>  testcases/kernel/containers/netns/netns_helper.sh | 54 +++++++++++++++++++----
>  1 file changed, 46 insertions(+), 8 deletions(-)
>
> diff --git a/testcases/kernel/containers/netns/netns_helper.sh b/testcases/kernel/containers/netns/netns_helper.sh
> index a95cdf2..8f7d3b5 100755
> --- a/testcases/kernel/containers/netns/netns_helper.sh
> +++ b/testcases/kernel/containers/netns/netns_helper.sh
> @@ -78,6 +78,42 @@ tst_check_iproute()
>  	fi
>  }
>  
> +check_ipv6_tentative()
> +{
> +	local info=$($NS_EXEC $NS_HANDLE0 $NS_TYPE ip -6 address show tentative 2>&1)
> +	local enabled=$($NS_EXEC $NS_HANDLE0 $NS_TYPE cat /proc/sys/net/ipv6/conf/all/accept_dad)
> +
> +	# With commits 35e015e1f577 and a2d3f3e33853, the global 'accept_dad'
> +	# flag is also taken into account (default value is 1). If either
> +	# global or per-interface flag is non-zero, DAD will be enabled on a
> +	# given interface.  With commit 094009531612, all.accept_dad is set to
> +	# 0 by default.
> +	if [ -n "$info" -a $enabled -eq 1 ]; then
> +		tst_resm TINFO "all.accept_dad was taken into account and set to 1 by default, and set it to 0 manually"
> +		echo 0 | $NS_EXEC $NS_HANDLE0 $NS_TYPE \
> +		tee /proc/sys/net/ipv6/conf/all/accept_dad >/dev/null
> +		echo 0 | $NS_EXEC $NS_HANDLE1 $NS_TYPE \
> +		tee /proc/sys/net/ipv6/conf/all/accept_dad >/dev/null
> +
> +		case $USE_IFCONFIG in
> +		1)
> +			$NS_EXEC $NS_HANDLE0 $NS_TYPE ifconfig veth0 down || \
> +				tst_brkm TBROK "disabling veth0 device failed"
> +			$NS_EXEC $NS_HANDLE1 $NS_TYPE ifconfig veth1 down || \
> +				tst_brkm TBROK "disabling veth1 device failed"
> +			;;
> +		*)
> +			$NS_EXEC $NS_HANDLE0 $NS_TYPE ip link set veth0 down || \
> +				tst_brkm TBROK "disabling veth0 device failed"
> +			$NS_EXEC $NS_HANDLE1 $NS_TYPE ip link set veth1 down || \
> +				tst_brkm TBROK "disabling veth1 device failed"
> +			;;
> +		esac
> +
> +		netns_set_ip
> +	fi
> +}
> +
>  ##
>  # Sets up global variables which can be used in test cases (documented above),
>  # creates two network namespaces and a pair of virtual ethernet devices, each
> @@ -174,6 +210,8 @@ netns_setup()
>  	esac
>  
>  	netns_set_ip
> +
> +	[ "$2" = "ipv6" ] && check_ipv6_tentative
>  }
>  
>  ##
> @@ -265,23 +303,23 @@ netns_set_ip()
>  
>  	case $USE_IFCONFIG in
>  	1)
> -		$NS_EXEC $NS_HANDLE0 $NS_TYPE ifconfig veth0 $IFCONF_IN6_ARG $IP0/$NETMASK ||
> +		$NS_EXEC $NS_HANDLE0 $NS_TYPE ifconfig veth0 $IFCONF_IN6_ARG $IP0/$NETMASK || \
>  			tst_brkm TBROK "adding address to veth0 failed"
> -		$NS_EXEC $NS_HANDLE1 $NS_TYPE ifconfig veth1 $IFCONF_IN6_ARG $IP1/$NETMASK ||
> +		$NS_EXEC $NS_HANDLE1 $NS_TYPE ifconfig veth1 $IFCONF_IN6_ARG $IP1/$NETMASK || \
>  			tst_brkm TBROK "adding address to veth1 failed"
> -		$NS_EXEC $NS_HANDLE0 $NS_TYPE ifconfig veth0 up ||
> +		$NS_EXEC $NS_HANDLE0 $NS_TYPE ifconfig veth0 up || \
>  			tst_brkm TBROK "enabling veth0 device failed"
> -		$NS_EXEC $NS_HANDLE1 $NS_TYPE ifconfig veth1 up ||
> +		$NS_EXEC $NS_HANDLE1 $NS_TYPE ifconfig veth1 up || \
>  			tst_brkm TBROK "enabling veth1 device failed"
>  		;;
>  	*)
> -		$NS_EXEC $NS_HANDLE0 $NS_TYPE ip address add $IP0/$NETMASK dev veth0 ||
> +		$NS_EXEC $NS_HANDLE0 $NS_TYPE ip address add $IP0/$NETMASK dev veth0 || \
>  			tst_brkm TBROK "adding address to veth0 failed"
> -		$NS_EXEC $NS_HANDLE1 $NS_TYPE ip address add $IP1/$NETMASK dev veth1 ||
> +		$NS_EXEC $NS_HANDLE1 $NS_TYPE ip address add $IP1/$NETMASK dev veth1 || \
>  			tst_brkm TBROK "adding address to veth1 failed"
> -		$NS_EXEC $NS_HANDLE0 $NS_TYPE ip link set veth0 up ||
> +		$NS_EXEC $NS_HANDLE0 $NS_TYPE ip link set veth0 up || \
>  			tst_brkm TBROK "enabling veth0 device failed"
> -		$NS_EXEC $NS_HANDLE1 $NS_TYPE ip link set veth1 up ||
> +		$NS_EXEC $NS_HANDLE1 $NS_TYPE ip link set veth1 up || \
>  			tst_brkm TBROK "enabling veth1 device failed"
>  		;;
>  	esac