[PATCH net v3 0/3] bonding: properly restore flags when bond changes ether type

[PATCH net v3 0/3] bonding: properly restore flags when bond changes ether type

[Nikolay Aleksandrov]

Hi,
A bug was reported by syzbot[1] that causes a warning and a myriad of
other potential issues if a bond, that is also a slave, fails to enslave a
non-eth device. While fixing that bug I found that we have the same
issues when such enslave passes and after that the bond changes back to
ARPHRD_ETHER (again due to ether_setup). This set fixes all issues by
extracting the ether_setup() sequence in a helper which does the right
thing about bond flags when it needs to change back to ARPHRD_ETHER. It
also adds selftests for these cases.

Patch 01 adds the new bond_ether_setup helper and fixes the issues when a
bond device changes its ether type due to successful enslave. Patch 02
fixes the issues when it changes its ether type due to an unsuccessful
enslave. Note we need two patches because the bugs were introduced by
different commits. Patch 03 adds the new selftests.

Due to the comment adjustment and squash, could you please review
patch 01 again? I've kept the other acks since there were no code
changes.

v3: squash the helper patch and the first fix, adjust the comment above
    it to be explicit about the bond device, no code changes
v2: new set, all patches are new due to new approach of fixing these bugs

Thanks,
 Nik

[1] https://syzkaller.appspot.com/bug?id=391c7b1f6522182899efba27d891f1743e8eb3ef

Nikolay Aleksandrov (3):
  bonding: restore IFF_MASTER/SLAVE flags on bond enslave ether type
    change
  bonding: restore bond's IFF_SLAVE flag if a non-eth dev enslave fails
  selftests: bonding: add tests for ether type changes

 drivers/net/bonding/bond_main.c               | 23 +++--
 .../selftests/drivers/net/bonding/Makefile    |  3 +-
 .../net/bonding/bond-eth-type-change.sh       | 85 +++++++++++++++++++
 3 files changed, 103 insertions(+), 8 deletions(-)
 create mode 100755 tools/testing/selftests/drivers/net/bonding/bond-eth-type-change.sh

-- 
2.39.1

[PATCH net v3 1/3] bonding: restore IFF_MASTER/SLAVE flags on bond enslave ether type change

[Nikolay Aleksandrov]

Add bond_ether_setup helper which is used to fix ether_setup() calls in the
bonding driver. It takes care of both IFF_MASTER and IFF_SLAVE flags, the
former is always restored and the latter only if it was set.
If the bond enslaves non-ARPHRD_ETHER device (changes its type), then
releases it and enslaves ARPHRD_ETHER device (changes back) then we
use ether_setup() to restore the bond device type but it also resets its
flags and removes IFF_MASTER and IFF_SLAVE[1]. Use the bond_ether_setup
helper to restore both after such transition.

[1] reproduce (nlmon is non-ARPHRD_ETHER):
 $ ip l add nlmon0 type nlmon
 $ ip l add bond2 type bond mode active-backup
 $ ip l set nlmon0 master bond2
 $ ip l set nlmon0 nomaster
 $ ip l add bond1 type bond
 (we use bond1 as ARPHRD_ETHER device to restore bond2's mode)
 $ ip l set bond1 master bond2
 $ ip l sh dev bond2
 37: bond2: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether be:d7:c5:40:5b:cc brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 1500
 (notice bond2's IFF_MASTER is missing)

Fixes: e36b9d16c6a6 ("bonding: clean muticast addresses when device changes type")
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
---
v3: squashed patch 01 with the helper into this one, adjusted the
comment to be more explicit, no code changes

 drivers/net/bonding/bond_main.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 00646aa315c3..4bd911f9d3f9 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1775,6 +1775,19 @@ void bond_lower_state_changed(struct slave *slave)
 		slave_err(bond_dev, slave_dev, "Error: %s\n", errmsg);	\
 } while (0)
 
+/* The bonding driver uses ether_setup() to convert a master bond device
+ * to ARPHRD_ETHER, that resets the target netdevice's flags so we always
+ * have to restore the IFF_MASTER flag, and only restore IFF_SLAVE if it was set
+ */
+static void bond_ether_setup(struct net_device *bond_dev)
+{
+	unsigned int slave_flag = bond_dev->flags & IFF_SLAVE;
+
+	ether_setup(bond_dev);
+	bond_dev->flags |= IFF_MASTER | slave_flag;
+	bond_dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+}
+
 /* enslave device <slave> to bond device <master> */
 int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 		 struct netlink_ext_ack *extack)
@@ -1866,10 +1879,8 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 
 			if (slave_dev->type != ARPHRD_ETHER)
 				bond_setup_by_slave(bond_dev, slave_dev);
-			else {
-				ether_setup(bond_dev);
-				bond_dev->priv_flags &= ~IFF_TX_SKB_SHARING;
-			}
+			else
+				bond_ether_setup(bond_dev);
 
 			call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE,
 						 bond_dev);
-- 
2.39.1

[PATCH net v3 2/3] bonding: restore bond's IFF_SLAVE flag if a non-eth dev enslave fails

[Nikolay Aleksandrov]

syzbot reported a warning[1] where the bond device itself is a slave and
we try to enslave a non-ethernet device as the first slave which fails
but then in the error path when ether_setup() restores the bond device
it also clears all flags. In my previous fix[2] I restored the
IFF_MASTER flag, but I didn't consider the case that the bond device
itself might also be a slave with IFF_SLAVE set, so we need to restore
that flag as well. Use the bond_ether_setup helper which does the right
thing and restores the bond's flags properly.

Steps to reproduce using a nlmon dev:
 $ ip l add nlmon0 type nlmon
 $ ip l add bond1 type bond
 $ ip l add bond2 type bond
 $ ip l set bond1 master bond2
 $ ip l set dev nlmon0 master bond1
 $ ip -d l sh dev bond1
 22: bond1: <BROADCAST,MULTICAST,MASTER> mtu 1500 qdisc noqueue master bond2 state DOWN mode DEFAULT group default qlen 1000
 (now bond1's IFF_SLAVE flag is gone and we'll hit a warning[3] if we
  try to delete it)

[1] https://syzkaller.appspot.com/bug?id=391c7b1f6522182899efba27d891f1743e8eb3ef
[2] commit 7d5cd2ce5292 ("bonding: correctly handle bonding type change on enslave failure")
[3] example warning:
 [   27.008664] bond1: (slave nlmon0): The slave device specified does not support setting the MAC address
 [   27.008692] bond1: (slave nlmon0): Error -95 calling set_mac_address
 [   32.464639] bond1 (unregistering): Released all slaves
 [   32.464685] ------------[ cut here ]------------
 [   32.464686] WARNING: CPU: 1 PID: 2004 at net/core/dev.c:10829 unregister_netdevice_many+0x72a/0x780
 [   32.464694] Modules linked in: br_netfilter bridge bonding virtio_net
 [   32.464699] CPU: 1 PID: 2004 Comm: ip Kdump: loaded Not tainted 5.18.0-rc3+ #47
 [   32.464703] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.1-2.fc37 04/01/2014
 [   32.464704] RIP: 0010:unregister_netdevice_many+0x72a/0x780
 [   32.464707] Code: 99 fd ff ff ba 90 1a 00 00 48 c7 c6 f4 02 66 96 48 c7 c7 20 4d 35 96 c6 05 fa c7 2b 02 01 e8 be 6f 4a 00 0f 0b e9 73 fd ff ff <0f> 0b e9 5f fd ff ff 80 3d e3 c7 2b 02 00 0f 85 3b fd ff ff ba 59
 [   32.464710] RSP: 0018:ffffa006422d7820 EFLAGS: 00010206
 [   32.464712] RAX: ffff8f6e077140a0 RBX: ffffa006422d7888 RCX: 0000000000000000
 [   32.464714] RDX: ffff8f6e12edbe58 RSI: 0000000000000296 RDI: ffffffff96d4a520
 [   32.464716] RBP: ffff8f6e07714000 R08: ffffffff96d63600 R09: ffffa006422d7728
 [   32.464717] R10: 0000000000000ec0 R11: ffffffff9698c988 R12: ffff8f6e12edb140
 [   32.464719] R13: dead000000000122 R14: dead000000000100 R15: ffff8f6e12edb140
 [   32.464723] FS:  00007f297c2f1740(0000) GS:ffff8f6e5d900000(0000) knlGS:0000000000000000
 [   32.464725] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [   32.464726] CR2: 00007f297bf1c800 CR3: 00000000115e8000 CR4: 0000000000350ee0
 [   32.464730] Call Trace:
 [   32.464763]  <TASK>
 [   32.464767]  rtnl_dellink+0x13e/0x380
 [   32.464776]  ? cred_has_capability.isra.0+0x68/0x100
 [   32.464780]  ? __rtnl_unlock+0x33/0x60
 [   32.464783]  ? bpf_lsm_capset+0x10/0x10
 [   32.464786]  ? security_capable+0x36/0x50
 [   32.464790]  rtnetlink_rcv_msg+0x14e/0x3b0
 [   32.464792]  ? _copy_to_iter+0xb1/0x790
 [   32.464796]  ? post_alloc_hook+0xa0/0x160
 [   32.464799]  ? rtnl_calcit.isra.0+0x110/0x110
 [   32.464802]  netlink_rcv_skb+0x50/0xf0
 [   32.464806]  netlink_unicast+0x216/0x340
 [   32.464809]  netlink_sendmsg+0x23f/0x480
 [   32.464812]  sock_sendmsg+0x5e/0x60
 [   32.464815]  ____sys_sendmsg+0x22c/0x270
 [   32.464818]  ? import_iovec+0x17/0x20
 [   32.464821]  ? sendmsg_copy_msghdr+0x59/0x90
 [   32.464823]  ? do_set_pte+0xa0/0xe0
 [   32.464828]  ___sys_sendmsg+0x81/0xc0
 [   32.464832]  ? mod_objcg_state+0xc6/0x300
 [   32.464835]  ? refill_obj_stock+0xa9/0x160
 [   32.464838]  ? memcg_slab_free_hook+0x1a5/0x1f0
 [   32.464842]  __sys_sendmsg+0x49/0x80
 [   32.464847]  do_syscall_64+0x3b/0x90
 [   32.464851]  entry_SYSCALL_64_after_hwframe+0x44/0xae
 [   32.464865] RIP: 0033:0x7f297bf2e5e7
 [   32.464868] Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
 [   32.464869] RSP: 002b:00007ffd96c824c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 [   32.464872] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f297bf2e5e7
 [   32.464874] RDX: 0000000000000000 RSI: 00007ffd96c82540 RDI: 0000000000000003
 [   32.464875] RBP: 00000000640f19de R08: 0000000000000001 R09: 000000000000007c
 [   32.464876] R10: 00007f297bffabe0 R11: 0000000000000246 R12: 0000000000000001
 [   32.464877] R13: 00007ffd96c82d20 R14: 00007ffd96c82610 R15: 000055bfe38a7020
 [   32.464881]  </TASK>
 [   32.464882] ---[ end trace 0000000000000000 ]---

Fixes: 7d5cd2ce5292 ("bonding: correctly handle bonding type change on enslave failure")
Reported-by: syzbot+9dfc3f3348729cc82277@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=391c7b1f6522182899efba27d891f1743e8eb3ef
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Acked-by: Jonathan Toppins <jtoppins@redhat.com>
Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
---
v3: no changes

 drivers/net/bonding/bond_main.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 4bd911f9d3f9..236e5219c811 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2300,9 +2300,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 			eth_hw_addr_random(bond_dev);
 		if (bond_dev->type != ARPHRD_ETHER) {
 			dev_close(bond_dev);
-			ether_setup(bond_dev);
-			bond_dev->flags |= IFF_MASTER;
-			bond_dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+			bond_ether_setup(bond_dev);
 		}
 	}
 
-- 
2.39.1

[PATCH net v3 3/3] selftests: bonding: add tests for ether type changes

[Nikolay Aleksandrov]

Add new network selftests for the bonding device which exercise the ether
type changing call paths. They also test for the recent syzbot bug[1] which
causes a warning and results in wrong device flags (IFF_SLAVE missing).
The test adds three bond devices and a nlmon device, enslaves one of the
bond devices to the other and then uses the nlmon device for successful
and unsuccesful enslaves both of which change the bond ether type. Thus
we can test for both MASTER and SLAVE flags at the same time.

If the flags are properly restored we get:
TEST: Change ether type of an enslaved bond device with unsuccessful enslave   [ OK ]
TEST: Change ether type of an enslaved bond device with successful enslave   [ OK ]

[1] https://syzkaller.appspot.com/bug?id=391c7b1f6522182899efba27d891f1743e8eb3ef

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Acked-by: Jonathan Toppins <jtoppins@redhat.com>
Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
---
v3: no changes

 .../selftests/drivers/net/bonding/Makefile    |  3 +-
 .../net/bonding/bond-eth-type-change.sh       | 85 +++++++++++++++++++
 2 files changed, 87 insertions(+), 1 deletion(-)
 create mode 100755 tools/testing/selftests/drivers/net/bonding/bond-eth-type-change.sh

diff --git a/tools/testing/selftests/drivers/net/bonding/Makefile b/tools/testing/selftests/drivers/net/bonding/Makefile
index 8e3b786a748f..a39bb2560d9b 100644
--- a/tools/testing/selftests/drivers/net/bonding/Makefile
+++ b/tools/testing/selftests/drivers/net/bonding/Makefile
@@ -8,7 +8,8 @@ TEST_PROGS := \
 	dev_addr_lists.sh \
 	mode-1-recovery-updelay.sh \
 	mode-2-recovery-updelay.sh \
-	option_prio.sh
+	option_prio.sh \
+	bond-eth-type-change.sh
 
 TEST_FILES := \
 	lag_lib.sh \
diff --git a/tools/testing/selftests/drivers/net/bonding/bond-eth-type-change.sh b/tools/testing/selftests/drivers/net/bonding/bond-eth-type-change.sh
new file mode 100755
index 000000000000..5cdd22048ba7
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/bonding/bond-eth-type-change.sh
@@ -0,0 +1,85 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test bond device ether type changing
+#
+
+ALL_TESTS="
+	bond_test_unsuccessful_enslave_type_change
+	bond_test_successful_enslave_type_change
+"
+REQUIRE_MZ=no
+NUM_NETIFS=0
+lib_dir=$(dirname "$0")
+source "$lib_dir"/net_forwarding_lib.sh
+
+bond_check_flags()
+{
+	local bonddev=$1
+
+	ip -d l sh dev "$bonddev" | grep -q "MASTER"
+	check_err $? "MASTER flag is missing from the bond device"
+
+	ip -d l sh dev "$bonddev" | grep -q "SLAVE"
+	check_err $? "SLAVE flag is missing from the bond device"
+}
+
+# test enslaved bond dev type change from ARPHRD_ETHER and back
+# this allows us to test both MASTER and SLAVE flags at once
+bond_test_enslave_type_change()
+{
+	local test_success=$1
+	local devbond0="test-bond0"
+	local devbond1="test-bond1"
+	local devbond2="test-bond2"
+	local nonethdev="test-noneth0"
+
+	# create a non-ARPHRD_ETHER device for testing (e.g. nlmon type)
+	ip link add name "$nonethdev" type nlmon
+	check_err $? "could not create a non-ARPHRD_ETHER device (nlmon)"
+	ip link add name "$devbond0" type bond
+	if [ $test_success -eq 1 ]; then
+		# we need devbond0 in active-backup mode to successfully enslave nonethdev
+		ip link set dev "$devbond0" type bond mode active-backup
+		check_err $? "could not change bond mode to active-backup"
+	fi
+	ip link add name "$devbond1" type bond
+	ip link add name "$devbond2" type bond
+	ip link set dev "$devbond0" master "$devbond1"
+	check_err $? "could not enslave $devbond0 to $devbond1"
+	# change bond type to non-ARPHRD_ETHER
+	ip link set dev "$nonethdev" master "$devbond0" 1>/dev/null 2>/dev/null
+	ip link set dev "$nonethdev" nomaster 1>/dev/null 2>/dev/null
+	# restore ARPHRD_ETHER type by enslaving such device
+	ip link set dev "$devbond2" master "$devbond0"
+	check_err $? "could not enslave $devbond2 to $devbond0"
+	ip link set dev "$devbond1" nomaster
+
+	bond_check_flags "$devbond0"
+
+	# clean up
+	ip link del dev "$devbond0"
+	ip link del dev "$devbond1"
+	ip link del dev "$devbond2"
+	ip link del dev "$nonethdev"
+}
+
+bond_test_unsuccessful_enslave_type_change()
+{
+	RET=0
+
+	bond_test_enslave_type_change 0
+	log_test "Change ether type of an enslaved bond device with unsuccessful enslave"
+}
+
+bond_test_successful_enslave_type_change()
+{
+	RET=0
+
+	bond_test_enslave_type_change 1
+	log_test "Change ether type of an enslaved bond device with successful enslave"
+}
+
+tests_run
+
+exit "$EXIT_STATUS"
-- 
2.39.1

Re: [PATCH net v3 0/3] bonding: properly restore flags when bond changes ether type

[Jonathan Toppins]

On 3/15/23 07:18, Nikolay Aleksandrov wrote:
> Hi,
> A bug was reported by syzbot[1] that causes a warning and a myriad of
> other potential issues if a bond, that is also a slave, fails to enslave a
> non-eth device. While fixing that bug I found that we have the same
> issues when such enslave passes and after that the bond changes back to
> ARPHRD_ETHER (again due to ether_setup). This set fixes all issues by
> extracting the ether_setup() sequence in a helper which does the right
> thing about bond flags when it needs to change back to ARPHRD_ETHER. It
> also adds selftests for these cases.
> 
> Patch 01 adds the new bond_ether_setup helper and fixes the issues when a
> bond device changes its ether type due to successful enslave. Patch 02
> fixes the issues when it changes its ether type due to an unsuccessful
> enslave. Note we need two patches because the bugs were introduced by
> different commits. Patch 03 adds the new selftests.
> 
> Due to the comment adjustment and squash, could you please review
> patch 01 again? I've kept the other acks since there were no code
> changes.
> 
> v3: squash the helper patch and the first fix, adjust the comment above
>      it to be explicit about the bond device, no code changes
> v2: new set, all patches are new due to new approach of fixing these bugs
> 
> Thanks,
>   Nik
> 
> [1] https://syzkaller.appspot.com/bug?id=391c7b1f6522182899efba27d891f1743e8eb3ef
> 
> Nikolay Aleksandrov (3):
>    bonding: restore IFF_MASTER/SLAVE flags on bond enslave ether type
>      change
>    bonding: restore bond's IFF_SLAVE flag if a non-eth dev enslave fails
>    selftests: bonding: add tests for ether type changes
> 
>   drivers/net/bonding/bond_main.c               | 23 +++--
>   .../selftests/drivers/net/bonding/Makefile    |  3 +-
>   .../net/bonding/bond-eth-type-change.sh       | 85 +++++++++++++++++++
>   3 files changed, 103 insertions(+), 8 deletions(-)
>   create mode 100755 tools/testing/selftests/drivers/net/bonding/bond-eth-type-change.sh
> 

    For the series.
Acked-by: Jonathan Toppins <jtoppins@redhat.com>

Re: [PATCH net v3 0/3] bonding: properly restore flags when bond changes ether type

[Michal Kubiak]

On Wed, Mar 15, 2023 at 01:18:39PM +0200, Nikolay Aleksandrov wrote:
> Hi,
> A bug was reported by syzbot[1] that causes a warning and a myriad of
> other potential issues if a bond, that is also a slave, fails to enslave a
> non-eth device. While fixing that bug I found that we have the same
> issues when such enslave passes and after that the bond changes back to
> ARPHRD_ETHER (again due to ether_setup). This set fixes all issues by
> extracting the ether_setup() sequence in a helper which does the right
> thing about bond flags when it needs to change back to ARPHRD_ETHER. It
> also adds selftests for these cases.
> 
> Patch 01 adds the new bond_ether_setup helper and fixes the issues when a
> bond device changes its ether type due to successful enslave. Patch 02
> fixes the issues when it changes its ether type due to an unsuccessful
> enslave. Note we need two patches because the bugs were introduced by
> different commits. Patch 03 adds the new selftests.
> 
> Due to the comment adjustment and squash, could you please review
> patch 01 again? I've kept the other acks since there were no code
> changes.
> 
> v3: squash the helper patch and the first fix, adjust the comment above
>     it to be explicit about the bond device, no code changes
> v2: new set, all patches are new due to new approach of fixing these bugs
> 
> Thanks,
>  Nik
> 
> [1] https://syzkaller.appspot.com/bug?id=391c7b1f6522182899efba27d891f1743e8eb3ef
> 
> Nikolay Aleksandrov (3):
>   bonding: restore IFF_MASTER/SLAVE flags on bond enslave ether type
>     change
>   bonding: restore bond's IFF_SLAVE flag if a non-eth dev enslave fails
>   selftests: bonding: add tests for ether type changes
> 
>  drivers/net/bonding/bond_main.c               | 23 +++--
>  .../selftests/drivers/net/bonding/Makefile    |  3 +-
>  .../net/bonding/bond-eth-type-change.sh       | 85 +++++++++++++++++++
>  3 files changed, 103 insertions(+), 8 deletions(-)
>  create mode 100755 tools/testing/selftests/drivers/net/bonding/bond-eth-type-change.sh
> 


For the series.
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>

Thanks,
Michal

> -- 
> 2.39.1
> 

Re: [PATCH net v3 0/3] bonding: properly restore flags when bond changes ether type

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (main)
by David S. Miller <davem@davemloft.net>:

On Wed, 15 Mar 2023 13:18:39 +0200 you wrote:
> Hi,
> A bug was reported by syzbot[1] that causes a warning and a myriad of
> other potential issues if a bond, that is also a slave, fails to enslave a
> non-eth device. While fixing that bug I found that we have the same
> issues when such enslave passes and after that the bond changes back to
> ARPHRD_ETHER (again due to ether_setup). This set fixes all issues by
> extracting the ether_setup() sequence in a helper which does the right
> thing about bond flags when it needs to change back to ARPHRD_ETHER. It
> also adds selftests for these cases.
> 
> [...]

Here is the summary with links:
  - [net,v3,1/3] bonding: restore IFF_MASTER/SLAVE flags on bond enslave ether type change
    https://git.kernel.org/netdev/net/c/9ec7eb60dcbc
  - [net,v3,2/3] bonding: restore bond's IFF_SLAVE flag if a non-eth dev enslave fails
    https://git.kernel.org/netdev/net/c/e667d4690986
  - [net,v3,3/3] selftests: bonding: add tests for ether type changes
    https://git.kernel.org/netdev/net/c/222c94ec0ad4

You are awesome, thank you!
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