Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from David Miller:

 1) Fix type of bind option flag in af_xdp, from Baruch Siach.

 2) Fix use after free in bpf_xdp_link_release(), from Xuan Zhao.

 3) PM refcnt imbakance in r8152, from Takashi Iwai.

 4) Sign extension ug in liquidio, from Colin Ian King.

 5) Mising range check in s390 bpf jit, from Colin Ian King.

 6) Uninit value in caif_seqpkt_sendmsg(), from Ziyong Xuan.

 7) Fix skb page recycling race, from Ilias Apalodimas.

 8) Fix memory leak in tcindex_partial_destroy_work, from Pave Skripkin.

 9) netrom timer sk refcnt issues, from Nguyen Dinh Phi.

10) Fix data races aroun tcp's tfo_active_disable_stamp, from Eric
    Dumazet.

11) act_skbmod should only operate on ethernet packets, from Peilin Ye.

12) Fix slab out-of-bpunds in fib6_nh_flush_exceptions(),, from Psolo
    Abeni.

13) Fix sparx5 dependencies, from Yajun Deng.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (74 commits)
  dpaa2-switch: seed the buffer pool after allocating the swp
  net: sched: cls_api: Fix the the wrong parameter
  net: sparx5: fix unmet dependencies warning
  net: dsa: tag_ksz: dont let the hardware process the layer 4 checksum
  net: dsa: ensure linearized SKBs in case of tail taggers
  ravb: Remove extra TAB
  ravb: Fix a typo in comment
  net: dsa: sja1105: make VID 4095 a bridge VLAN too
  tcp: disable TFO blackhole logic by default
  sctp: do not update transport pathmtu if SPP_PMTUD_ENABLE is not set
  net: ixp46x: fix ptp build failure
  ibmvnic: Remove the proper scrq flush
  selftests: net: add ESP-in-UDP PMTU test
  udp: check encap socket in __udp_lib_err
  sctp: update active_key for asoc when old key is being replaced
  r8169: Avoid duplicate sysfs entry creation error
  ixgbe: Fix packet corruption due to missing DMA sync
  Revert "qed: fix possible unpaired spin_{un}lock_bh in _qed_mcp_cmd_and_union()"
  ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions
  fsl/fman: Add fibre support
  ...

3 files changed, 265 insertions, 7 deletions

diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c
index 1828bba19020..dc6daa193557 100644
--- a/tools/bpf/bpftool/common.c
+++ b/tools/bpf/bpftool/common.c
@@ -222,6 +222,11 @@ int mount_bpffs_for_pin(const char *name)
 	int err = 0;
 
 	file = malloc(strlen(name) + 1);
+	if (!file) {
+		p_err("mem alloc failed");
+		return -1;
+	}
+
 	strcpy(file, name);
 	dir = dirname(file);
 
diff --git a/tools/testing/selftests/net/nettest.c b/tools/testing/selftests/net/nettest.c
index 6365c7fd1262..bd6288302094 100644
--- a/tools/testing/selftests/net/nettest.c
+++ b/tools/testing/selftests/net/nettest.c
@@ -11,9 +11,11 @@
 #include <sys/socket.h>
 #include <sys/wait.h>
 #include <linux/tcp.h>
+#include <linux/udp.h>
 #include <arpa/inet.h>
 #include <net/if.h>
 #include <netinet/in.h>
+#include <netinet/ip.h>
 #include <netdb.h>
 #include <fcntl.h>
 #include <libgen.h>
@@ -27,6 +29,10 @@
 #include <time.h>
 #include <errno.h>
 
+#include <linux/xfrm.h>
+#include <linux/ipsec.h>
+#include <linux/pfkeyv2.h>
+
 #ifndef IPV6_UNICAST_IF
 #define IPV6_UNICAST_IF         76
 #endif
@@ -114,6 +120,9 @@ struct sock_args {
 		struct in_addr  in;
 		struct in6_addr in6;
 	} expected_raddr;
+
+	/* ESP in UDP encap test */
+	int use_xfrm;
 };
 
 static int server_mode;
@@ -1346,6 +1355,41 @@ static int bind_socket(int sd, struct sock_args *args)
 	return 0;
 }
 
+static int config_xfrm_policy(int sd, struct sock_args *args)
+{
+	struct xfrm_userpolicy_info policy = {};
+	int type = UDP_ENCAP_ESPINUDP;
+	int xfrm_af = IP_XFRM_POLICY;
+	int level = SOL_IP;
+
+	if (args->type != SOCK_DGRAM) {
+		log_error("Invalid socket type. Only DGRAM could be used for XFRM\n");
+		return 1;
+	}
+
+	policy.action = XFRM_POLICY_ALLOW;
+	policy.sel.family = args->version;
+	if (args->version == AF_INET6) {
+		xfrm_af = IPV6_XFRM_POLICY;
+		level = SOL_IPV6;
+	}
+
+	policy.dir = XFRM_POLICY_OUT;
+	if (setsockopt(sd, level, xfrm_af, &policy, sizeof(policy)) < 0)
+		return 1;
+
+	policy.dir = XFRM_POLICY_IN;
+	if (setsockopt(sd, level, xfrm_af, &policy, sizeof(policy)) < 0)
+		return 1;
+
+	if (setsockopt(sd, IPPROTO_UDP, UDP_ENCAP, &type, sizeof(type)) < 0) {
+		log_err_errno("Failed to set xfrm encap");
+		return 1;
+	}
+
+	return 0;
+}
+
 static int lsock_init(struct sock_args *args)
 {
 	long flags;
@@ -1389,6 +1433,11 @@ static int lsock_init(struct sock_args *args)
 	if (fcntl(sd, F_SETFD, FD_CLOEXEC) < 0)
 		log_err_errno("Failed to set close-on-exec flag");
 
+	if (args->use_xfrm && config_xfrm_policy(sd, args)) {
+		log_err_errno("Failed to set xfrm policy");
+		goto err;
+	}
+
 out:
 	return sd;
 
@@ -1772,7 +1821,7 @@ static int ipc_parent(int cpid, int fd, struct sock_args *args)
 	return client_status;
 }
 
-#define GETOPT_STR  "sr:l:c:p:t:g:P:DRn:M:X:m:d:I:BN:O:SCi6L:0:1:2:3:Fbq"
+#define GETOPT_STR  "sr:l:c:p:t:g:P:DRn:M:X:m:d:I:BN:O:SCi6xL:0:1:2:3:Fbq"
 
 static void print_usage(char *prog)
 {
@@ -1795,6 +1844,7 @@ static void print_usage(char *prog)
 	"    -D|R          datagram (D) / raw (R) socket (default stream)\n"
 	"    -l addr       local address to bind to in server mode\n"
 	"    -c addr       local address to bind to in client mode\n"
+	"    -x            configure XFRM policy on socket\n"
 	"\n"
 	"    -d dev        bind socket to given device name\n"
 	"    -I dev        bind socket to given device name - server mode\n"
@@ -1966,6 +2016,9 @@ int main(int argc, char *argv[])
 		case 'q':
 			quiet = 1;
 			break;
+		case 'x':
+			args.use_xfrm = 1;
+			break;
 		default:
 			print_usage(argv[0]);
 			return 1;
diff --git a/tools/testing/selftests/net/pmtu.sh b/tools/testing/selftests/net/pmtu.sh
index 64cd2e23c568..543ad7513a8e 100755
--- a/tools/testing/selftests/net/pmtu.sh
+++ b/tools/testing/selftests/net/pmtu.sh
@@ -118,6 +118,16 @@
 #	below for IPv6 doesn't apply here, because, on IPv4, administrative MTU
 #	changes alone won't affect PMTU
 #
+# - pmtu_vti4_udp_exception
+#       Same as pmtu_vti4_exception, but using ESP-in-UDP
+#
+# - pmtu_vti4_udp_routed_exception
+#       Set up vti tunnel on top of veth connected through routing namespace and
+#	add xfrm states and policies with ESP-in-UDP encapsulation. Check that
+#	route exception is not created if link layer MTU is not exceeded, then
+#	lower MTU on second part of routed environment and check that exception
+#	is created with the expected PMTU.
+#
 # - pmtu_vti6_exception
 #	Set up vti6 tunnel on top of veth, with xfrm states and policies, in two
 #	namespaces with matching endpoints. Check that route exception is
@@ -125,6 +135,13 @@
 #	decrease and increase MTU of tunnel, checking that route exception PMTU
 #	changes accordingly
 #
+# - pmtu_vti6_udp_exception
+#       Same as pmtu_vti6_exception, but using ESP-in-UDP
+#
+# - pmtu_vti6_udp_routed_exception
+#	Same as pmtu_vti6_udp_routed_exception but with routing between vti
+#	endpoints
+#
 # - pmtu_vti4_default_mtu
 #	Set up vti4 tunnel on top of veth, in two namespaces with matching
 #	endpoints. Check that MTU assigned to vti interface is the MTU of the
@@ -224,6 +241,10 @@ tests="
 	pmtu_ipv6_ipv6_exception	IPv6 over IPv6: PMTU exceptions		1
 	pmtu_vti6_exception		vti6: PMTU exceptions			0
 	pmtu_vti4_exception		vti4: PMTU exceptions			0
+	pmtu_vti6_udp_exception		vti6: PMTU exceptions (ESP-in-UDP)	0
+	pmtu_vti4_udp_exception		vti4: PMTU exceptions (ESP-in-UDP)	0
+	pmtu_vti6_udp_routed_exception	vti6: PMTU exceptions, routed (ESP-in-UDP)	0
+	pmtu_vti4_udp_routed_exception	vti4: PMTU exceptions, routed (ESP-in-UDP)	0
 	pmtu_vti4_default_mtu		vti4: default MTU assignment		0
 	pmtu_vti6_default_mtu		vti6: default MTU assignment		0
 	pmtu_vti4_link_add_mtu		vti4: MTU setting on link creation	0
@@ -246,7 +267,6 @@ ns_b="ip netns exec ${NS_B}"
 ns_c="ip netns exec ${NS_C}"
 ns_r1="ip netns exec ${NS_R1}"
 ns_r2="ip netns exec ${NS_R2}"
-
 # Addressing and routing for tests with routers: four network segments, with
 # index SEGMENT between 1 and 4, a common prefix (PREFIX4 or PREFIX6) and an
 # identifier ID, which is 1 for hosts (A and B), 2 for routers (R1 and R2).
@@ -279,7 +299,6 @@ routes="
 	A	${prefix6}:${b_r2}::1	${prefix6}:${a_r2}::2
 	B	default			${prefix6}:${b_r1}::2
 "
-
 USE_NH="no"
 #	ns	family	nh id	   destination		gateway
 nexthops="
@@ -326,6 +345,7 @@ dummy6_mask="64"
 
 err_buf=
 tcpdump_pids=
+nettest_pids=
 
 err() {
 	err_buf="${err_buf}${1}
@@ -548,6 +568,14 @@ setup_vti6() {
 	setup_vti 6 ${veth6_a_addr} ${veth6_b_addr} ${tunnel6_a_addr} ${tunnel6_b_addr} ${tunnel6_mask}
 }
 
+setup_vti4routed() {
+	setup_vti 4 ${prefix4}.${a_r1}.1 ${prefix4}.${b_r1}.1 ${tunnel4_a_addr} ${tunnel4_b_addr} ${tunnel4_mask}
+}
+
+setup_vti6routed() {
+	setup_vti 6 ${prefix6}:${a_r1}::1 ${prefix6}:${b_r1}::1 ${tunnel6_a_addr} ${tunnel6_b_addr} ${tunnel6_mask}
+}
+
 setup_vxlan_or_geneve() {
 	type="${1}"
 	a_addr="${2}"
@@ -619,18 +647,36 @@ setup_xfrm() {
 	proto=${1}
 	veth_a_addr="${2}"
 	veth_b_addr="${3}"
+	encap=${4}
 
-	run_cmd ${ns_a} ip -${proto} xfrm state add src ${veth_a_addr} dst ${veth_b_addr} spi 0x1000 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel || return 1
-	run_cmd ${ns_a} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
+	run_cmd ${ns_a} ip -${proto} xfrm state add src ${veth_a_addr} dst ${veth_b_addr} spi 0x1000 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel ${encap} || return 1
+	run_cmd ${ns_a} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel ${encap}
 	run_cmd ${ns_a} ip -${proto} xfrm policy add dir out mark 10 tmpl src ${veth_a_addr} dst ${veth_b_addr} proto esp mode tunnel
 	run_cmd ${ns_a} ip -${proto} xfrm policy add dir in mark 10 tmpl src ${veth_b_addr} dst ${veth_a_addr} proto esp mode tunnel
 
-	run_cmd ${ns_b} ip -${proto} xfrm state add src ${veth_a_addr} dst ${veth_b_addr} spi 0x1000 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
-	run_cmd ${ns_b} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel
+	run_cmd ${ns_b} ip -${proto} xfrm state add src ${veth_a_addr} dst ${veth_b_addr} spi 0x1000 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel ${encap}
+	run_cmd ${ns_b} ip -${proto} xfrm state add src ${veth_b_addr} dst ${veth_a_addr} spi 0x1001 proto esp aead 'rfc4106(gcm(aes))' 0x0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f0f 128 mode tunnel ${encap}
 	run_cmd ${ns_b} ip -${proto} xfrm policy add dir out mark 10 tmpl src ${veth_b_addr} dst ${veth_a_addr} proto esp mode tunnel
 	run_cmd ${ns_b} ip -${proto} xfrm policy add dir in mark 10 tmpl src ${veth_a_addr} dst ${veth_b_addr} proto esp mode tunnel
 }
 
+setup_nettest_xfrm() {
+	which nettest >/dev/null
+	if [ $? -ne 0 ]; then
+		echo "'nettest' command not found; skipping tests"
+	        return 1
+	fi
+
+	[ ${1} -eq 6 ] && proto="-6" || proto=""
+	port=${2}
+
+	run_cmd ${ns_a} nettest ${proto} -q -D -s -x -p ${port} -t 5 &
+	nettest_pids="${nettest_pids} $!"
+
+	run_cmd ${ns_b} nettest ${proto} -q -D -s -x -p ${port} -t 5 &
+	nettest_pids="${nettest_pids} $!"
+}
+
 setup_xfrm4() {
 	setup_xfrm 4 ${veth4_a_addr} ${veth4_b_addr}
 }
@@ -639,6 +685,26 @@ setup_xfrm6() {
 	setup_xfrm 6 ${veth6_a_addr} ${veth6_b_addr}
 }
 
+setup_xfrm4udp() {
+	setup_xfrm 4 ${veth4_a_addr} ${veth4_b_addr} "encap espinudp 4500 4500 0.0.0.0"
+	setup_nettest_xfrm 4 4500
+}
+
+setup_xfrm6udp() {
+	setup_xfrm 6 ${veth6_a_addr} ${veth6_b_addr} "encap espinudp 4500 4500 0.0.0.0"
+	setup_nettest_xfrm 6 4500
+}
+
+setup_xfrm4udprouted() {
+	setup_xfrm 4 ${prefix4}.${a_r1}.1 ${prefix4}.${b_r1}.1 "encap espinudp 4500 4500 0.0.0.0"
+	setup_nettest_xfrm 4 4500
+}
+
+setup_xfrm6udprouted() {
+	setup_xfrm 6 ${prefix6}:${a_r1}::1 ${prefix6}:${b_r1}::1 "encap espinudp 4500 4500 0.0.0.0"
+	setup_nettest_xfrm 6 4500
+}
+
 setup_routing_old() {
 	for i in ${routes}; do
 		[ "${ns}" = "" ]	&& ns="${i}"		&& continue
@@ -823,6 +889,11 @@ cleanup() {
 	done
 	tcpdump_pids=
 
+	for pid in ${nettest_pids}; do
+		kill ${pid}
+	done
+	nettest_pids=
+
 	for n in ${NS_A} ${NS_B} ${NS_C} ${NS_R1} ${NS_R2}; do
 		ip netns del ${n} 2> /dev/null
 	done
@@ -1432,6 +1503,135 @@ test_pmtu_vti6_exception() {
 	return ${fail}
 }
 
+test_pmtu_vti4_udp_exception() {
+	setup namespaces veth vti4 xfrm4udp || return $ksft_skip
+	trace "${ns_a}" veth_a    "${ns_b}" veth_b \
+	      "${ns_a}" vti4_a    "${ns_b}" vti4_b
+
+	veth_mtu=1500
+	vti_mtu=$((veth_mtu - 20))
+
+	#                                UDP   SPI   SN   IV  ICV   pad length   next header
+	esp_payload_rfc4106=$((vti_mtu - 8   - 4   - 4  - 8 - 16  - 1          - 1))
+	ping_payload=$((esp_payload_rfc4106 - 28))
+
+	mtu "${ns_a}" veth_a ${veth_mtu}
+	mtu "${ns_b}" veth_b ${veth_mtu}
+	mtu "${ns_a}" vti4_a ${vti_mtu}
+	mtu "${ns_b}" vti4_b ${vti_mtu}
+
+	# Send DF packet without exceeding link layer MTU, check that no
+	# exception is created
+	run_cmd ${ns_a} ping -q -M want -i 0.1 -w 1 -s ${ping_payload} ${tunnel4_b_addr}
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel4_b_addr})"
+	check_pmtu_value "" "${pmtu}" "sending packet smaller than PMTU (IP payload length ${esp_payload_rfc4106})" || return 1
+
+	# Now exceed link layer MTU by one byte, check that exception is created
+	# with the right PMTU value
+	run_cmd ${ns_a} ping -q -M want -i 0.1 -w 1 -s $((ping_payload + 1)) ${tunnel4_b_addr}
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel4_b_addr})"
+	check_pmtu_value "${esp_payload_rfc4106}" "${pmtu}" "exceeding PMTU (IP payload length $((esp_payload_rfc4106 + 1)))"
+}
+
+test_pmtu_vti6_udp_exception() {
+	setup namespaces veth vti6 xfrm6udp || return $ksft_skip
+	trace "${ns_a}" veth_a    "${ns_b}" veth_b \
+	      "${ns_a}" vti6_a    "${ns_b}" vti6_b
+	fail=0
+
+	# Create route exception by exceeding link layer MTU
+	mtu "${ns_a}" veth_a 4000
+	mtu "${ns_b}" veth_b 4000
+	mtu "${ns_a}" vti6_a 5000
+	mtu "${ns_b}" vti6_b 5000
+	run_cmd ${ns_a} ${ping6} -q -i 0.1 -w 1 -s 60000 ${tunnel6_b_addr}
+
+	# Check that exception was created
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
+	check_pmtu_value any "${pmtu}" "creating tunnel exceeding link layer MTU" || return 1
+
+	# Decrease tunnel MTU, check for PMTU decrease in route exception
+	mtu "${ns_a}" vti6_a 3000
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
+	check_pmtu_value "3000" "${pmtu}" "decreasing tunnel MTU" || fail=1
+
+	# Increase tunnel MTU, check for PMTU increase in route exception
+	mtu "${ns_a}" vti6_a 9000
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
+	check_pmtu_value "9000" "${pmtu}" "increasing tunnel MTU" || fail=1
+
+	return ${fail}
+}
+
+test_pmtu_vti4_udp_routed_exception() {
+	setup namespaces routing vti4routed xfrm4udprouted || return $ksft_skip
+	trace "${ns_a}" veth_A-R1    "${ns_b}" veth_B-R1 \
+	      "${ns_a}" vti4_a       "${ns_b}" vti4_b
+
+	veth_mtu=1500
+	vti_mtu=$((veth_mtu - 20))
+
+	#                                UDP   SPI   SN   IV  ICV   pad length   next header
+	esp_payload_rfc4106=$((vti_mtu - 8   - 4   - 4  - 8 - 16  - 1          - 1))
+	ping_payload=$((esp_payload_rfc4106 - 28))
+
+        mtu "${ns_a}"  veth_A-R1 ${veth_mtu}
+        mtu "${ns_r1}" veth_R1-A ${veth_mtu}
+        mtu "${ns_b}"  veth_B-R1 ${veth_mtu}
+        mtu "${ns_r1}" veth_R1-B ${veth_mtu}
+
+	mtu "${ns_a}" vti4_a ${vti_mtu}
+	mtu "${ns_b}" vti4_b ${vti_mtu}
+
+	# Send DF packet without exceeding link layer MTU, check that no
+	# exception is created
+	run_cmd ${ns_a} ping -q -M want -i 0.1 -w 1 -s ${ping_payload} ${tunnel4_b_addr}
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel4_b_addr})"
+	check_pmtu_value "" "${pmtu}" "sending packet smaller than PMTU (IP payload length ${esp_payload_rfc4106})" || return 1
+
+	# Now decrease link layer MTU by 8 bytes on R1, check that exception is created
+	# with the right PMTU value
+        mtu "${ns_r1}" veth_R1-B $((veth_mtu - 8))
+	run_cmd ${ns_a} ping -q -M want -i 0.1 -w 1 -s $((ping_payload)) ${tunnel4_b_addr}
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel4_b_addr})"
+	check_pmtu_value "$((esp_payload_rfc4106 - 8))" "${pmtu}" "exceeding PMTU (IP payload length $((esp_payload_rfc4106)))"
+}
+
+test_pmtu_vti6_udp_routed_exception() {
+	setup namespaces routing vti6routed xfrm6udprouted || return $ksft_skip
+	trace "${ns_a}" veth_A-R1    "${ns_b}" veth_B-R1 \
+	      "${ns_a}" vti6_a       "${ns_b}" vti6_b
+
+	veth_mtu=1500
+	vti_mtu=$((veth_mtu - 40))
+
+	#                                UDP   SPI   SN   IV  ICV   pad length   next header
+	esp_payload_rfc4106=$((vti_mtu - 8   - 4   - 4  - 8 - 16  - 1          - 1))
+	ping_payload=$((esp_payload_rfc4106 - 48))
+
+        mtu "${ns_a}"  veth_A-R1 ${veth_mtu}
+        mtu "${ns_r1}" veth_R1-A ${veth_mtu}
+        mtu "${ns_b}"  veth_B-R1 ${veth_mtu}
+        mtu "${ns_r1}" veth_R1-B ${veth_mtu}
+
+	# mtu "${ns_a}" vti6_a ${vti_mtu}
+	# mtu "${ns_b}" vti6_b ${vti_mtu}
+
+	run_cmd ${ns_a} ${ping6} -q -M want -i 0.1 -w 1 -s ${ping_payload} ${tunnel6_b_addr}
+
+	# Check that exception was not created
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
+	check_pmtu_value "" "${pmtu}" "sending packet smaller than PMTU (IP payload length ${esp_payload_rfc4106})" || return 1
+
+	# Now decrease link layer MTU by 8 bytes on R1, check that exception is created
+	# with the right PMTU value
+        mtu "${ns_r1}" veth_R1-B $((veth_mtu - 8))
+	run_cmd ${ns_a} ${ping6} -q -M want -i 0.1 -w 1 -s $((ping_payload)) ${tunnel6_b_addr}
+	pmtu="$(route_get_dst_pmtu_from_exception "${ns_a}" ${tunnel6_b_addr})"
+	check_pmtu_value "$((esp_payload_rfc4106 - 8))" "${pmtu}" "exceeding PMTU (IP payload length $((esp_payload_rfc4106)))"
+
+}
+
 test_pmtu_vti4_default_mtu() {
 	setup namespaces veth vti4 || return $ksft_skip