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

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

[Xiao Yang]

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
-----------------------------------------------------------------------------------

We could fix this issue by waiting enough time(5s) for address
to pass duplicate address detection.

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
---
 testcases/kernel/containers/netns/netns_helper.sh | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/testcases/kernel/containers/netns/netns_helper.sh b/testcases/kernel/containers/netns/netns_helper.sh
index a95cdf2..72112c8 100755
--- a/testcases/kernel/containers/netns/netns_helper.sh
+++ b/testcases/kernel/containers/netns/netns_helper.sh
@@ -78,6 +78,16 @@ tst_check_iproute()
 	fi
 }
 
+check_ipv6_tentative()
+{
+	local info0=$($NS_EXEC $NS_HANDLE0 $NS_TYPE ip -6 address show tentative 2>&1)
+	local info1=$($NS_EXEC $NS_HANDLE1 $NS_TYPE ip -6 address show tentative 2>&1)
+
+	[ -z "$info0" ] && [ -z "$info1" ] && return 0
+
+	return 1;
+}
+
 ##
 # Sets up global variables which can be used in test cases (documented above),
 # creates two network namespaces and a pair of virtual ethernet devices, each
@@ -285,6 +295,16 @@ netns_set_ip()
 			tst_brkm TBROK "enabling veth1 device failed"
 		;;
 	esac
+
+	if [ "$tping" = "ping6" ]; then
+		for ((i=0; i<5; i++)); do
+			check_ipv6_tentative && return
+			tst_resm TINFO \
+				"address was in tentative state, wait and retry"
+			sleep 1
+		done
+		tst_brkm TBROK "address was always in tentative state"
+	fi
 }
 
 netns_ns_exec_cleanup()
-- 
1.8.3.1

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

[Alexey Kodanev]

On 12/15/2017 04:13 PM, 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
> -----------------------------------------------------------------------------------
> 
> We could fix this issue by waiting enough time(5s) for address
> to pass duplicate address detection.

netns tests disable DAD in setup so this shouldn't happen. It's quite
likely that the kernel doesn't have the following upstream patch-fix:

094009531612 ("ipv6: set all.accept_dad to 0 by default")

Thanks,
Alexey

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

[Xiao Yang]

On 2017/12/15 22:06, Alexey Kodanev wrote:
> On 12/15/2017 04:13 PM, 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
>> -----------------------------------------------------------------------------------
>>
>> We could fix this issue by waiting enough time(5s) for address
>> to pass duplicate address detection.
> netns tests disable DAD in setup so this shouldn't happen. It's quite
> likely that the kernel doesn't have the following upstream patch-fix:
>
> 094009531612 ("ipv6: set all.accept_dad to 0 by default")
Hi Alexey,

Thanks for your explanation.  The patch mentioned in your reply can fix 
the error.

Should we fix the error by setting all.accept_dad to 0 manually in netns 
or leave the
error to expose this issue?

Thanks,
Xiao Yang
> Thanks,
> Alexey
>
>
>

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

[Alexey Kodanev]

On 12/18/2017 05:50 AM, Xiao Yang wrote:
> On 2017/12/15 22:06, Alexey Kodanev wrote:
>> On 12/15/2017 04:13 PM, 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
>>> -----------------------------------------------------------------------------------
>>>
>>> We could fix this issue by waiting enough time(5s) for address
>>> to pass duplicate address detection.
>> netns tests disable DAD in setup so this shouldn't happen. It's quite
>> likely that the kernel doesn't have the following upstream patch-fix:
>>
>> 094009531612 ("ipv6: set all.accept_dad to 0 by default")
> Hi Alexey,
> 
> Thanks for your explanation.  The patch mentioned in your reply can fix 
> the error.
> 
> Should we fix the error by setting all.accept_dad to 0 manually in netns 
> or leave the
> error to expose this issue?

Ideally, we could check if the kernel is 4.14 and all.accept_dad
not equals 0, then apply workaround and print some warning message...

Anyway, I see that the patch in the queue for stable:
http://patchwork.ozlabs.org/bundle/davem/stable/?state=*

Thanks,
Alexey

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

[Xiao Yang]

On 2017/12/19 16:24, Alexey Kodanev wrote:
> On 12/18/2017 05:50 AM, Xiao Yang wrote:
>> On 2017/12/15 22:06, Alexey Kodanev wrote:
>>> On 12/15/2017 04:13 PM, 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
>>>> -----------------------------------------------------------------------------------
>>>>
>>>> We could fix this issue by waiting enough time(5s) for address
>>>> to pass duplicate address detection.
>>> netns tests disable DAD in setup so this shouldn't happen. It's quite
>>> likely that the kernel doesn't have the following upstream patch-fix:
>>>
>>> 094009531612 ("ipv6: set all.accept_dad to 0 by default")
>> Hi Alexey,
>>
>> Thanks for your explanation.  The patch mentioned in your reply can fix
>> the error.
>>
>> Should we fix the error by setting all.accept_dad to 0 manually in netns
>> or leave the
>> error to expose this issue?
> Ideally, we could check if the kernel is 4.14 and all.accept_dad
> not equals 0, then apply workaround and print some warning message...
Hi Alexey,

Checking kernel version seems unreliable because commit 35e015e1f577 and 
a2d3f3e33853
may be ported into some distros(e.g. RHEL7.5Alpha with kernel v3.10.0).

Thanks,
Xiao Yang
> Anyway, I see that the patch in the queue for stable:
> http://patchwork.ozlabs.org/bundle/davem/stable/?state=*
>
> Thanks,
> Alexey
>
>
>

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

[xiao yang]

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
-- 
1.8.3.1

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

[Xiao Yang]

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