Re: [BUG] [FIXED: TESTED] kmemleak in rtnetlink_rcv() triggered by selftests/drivers/net/team in build cdc9718d5e59

From: Mirsad Goran Todorovac
Date: Mon Apr 10 2023 - 13:34:38 EST

Next message: Srinivas Pandruvada: "[PATCH] thermal: intel: Fix unchecked MSR issue"
Previous message: Sean Christopherson: "Re: [PATCH v4 0/6] KVM: x86: Fix unpermitted XTILE CPUID reporting"
In reply to: Mirsad Goran Todorovac: "Re: [BUG] [FIXED: TESTED] kmemleak in rtnetlink_rcv() triggered by selftests/drivers/net/team in build cdc9718d5e59"
Next in thread: Mirsad Goran Todorovac: "Re: [BUG] [TESTING: HANG] kmemleak in rtnetlink_rcv() triggered by selftests/drivers/net/team in build cdc9718d5e59"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On 09. 04. 2023. 20:47, Mirsad Goran Todorovac wrote:
> On 09. 04. 2023. 19:14, Ido Schimmel wrote:
>> On Sun, Apr 09, 2023 at 01:49:30PM +0200, Mirsad Goran Todorovac wrote:
>>> Hi all,
>>>
>>> There appears to be a memleak triggered by the selftest drivers/net/team.
>>
>> Thanks for the report. Not sure it's related to team, see below.
>
> Not at all, I'm really encouraged that this leak is fixed so quickly and neatly.
>
> Now it isn't clear to me why I did not cut the possibility in half,
> but I assumed that it was the drivers/net/team, and it wouldn't work
> for me without the former.
>
> They say that the assumption is the mother of all blunders :-)
>
> I was lucky to choose the right entry function and the maintainers,
> at least I hope so.
>
> (Additionally, I saw that bond_enslave() is Jay and Andy's support, so
> I added them to Cc:, if that's not a problem.)
>
>>> # cat /sys/kernel/debug/kmemleak
>>> unreferenced object 0xffff8c18def8ee00 (size 256):
>>> comm "ip", pid 5727, jiffies 4294961159 (age 954.244s)
>>> hex dump (first 32 bytes):
>>> 00 20 09 de 18 8c ff ff 00 00 00 00 00 00 00 00 . ..............
>>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>> backtrace:
>>> [<ffffffffb60fb25c>] slab_post_alloc_hook+0x8c/0x3e0
>>> [<ffffffffb6102b39>] __kmem_cache_alloc_node+0x1d9/0x2a0
>>> [<ffffffffb607684e>] kmalloc_trace+0x2e/0xc0
>>> [<ffffffffb6dbc00b>] vlan_vid_add+0x11b/0x290
>>> [<ffffffffb6dbcffc>] vlan_device_event+0x19c/0x880
>>> [<ffffffffb5dde4d7>] raw_notifier_call_chain+0x47/0x70
>>> [<ffffffffb6ab6940>] call_netdevice_notifiers_info+0x50/0xa0
>>> [<ffffffffb6ac7574>] dev_open+0x94/0xa0
>>> [<ffffffffc176515e>] 0xffffffffc176515e
>>
>> Don't know what this is. Might be another issue.
>
> I really couldn't tell.
>
>>> [<ffffffffb6ada6b0>] do_set_master+0x90/0xb0
>>> [<ffffffffb6adc5f4>] do_setlink+0x514/0x11f0
>>> [<ffffffffb6ae4507>] __rtnl_newlink+0x4e7/0xa10
>>> [<ffffffffb6ae4a8c>] rtnl_newlink+0x4c/0x70
>>> [<ffffffffb6adf334>] rtnetlink_rcv_msg+0x184/0x5d0
>>> [<ffffffffb6b6ad1e>] netlink_rcv_skb+0x5e/0x110
>>> [<ffffffffb6ada0e9>] rtnetlink_rcv+0x19/0x20
>>> unreferenced object 0xffff8c18250d3700 (size 32):
>>> comm "ip", pid 5727, jiffies 4294961159 (age 954.244s)
>>> hex dump (first 32 bytes):
>>> a0 ee f8 de 18 8c ff ff a0 ee f8 de 18 8c ff ff ................
>>> 81 00 00 00 01 00 00 00 cc cc cc cc cc cc cc cc ................
>>> backtrace:
>>> [<ffffffffb60fb25c>] slab_post_alloc_hook+0x8c/0x3e0
>>> [<ffffffffb6102b39>] __kmem_cache_alloc_node+0x1d9/0x2a0
>>> [<ffffffffb607684e>] kmalloc_trace+0x2e/0xc0
>>> [<ffffffffb6dbc064>] vlan_vid_add+0x174/0x290
>>> [<ffffffffb6dbcffc>] vlan_device_event+0x19c/0x880
>>> [<ffffffffb5dde4d7>] raw_notifier_call_chain+0x47/0x70
>>> [<ffffffffb6ab6940>] call_netdevice_notifiers_info+0x50/0xa0
>>> [<ffffffffb6ac7574>] dev_open+0x94/0xa0
>>> [<ffffffffc176515e>] 0xffffffffc176515e
>>> [<ffffffffb6ada6b0>] do_set_master+0x90/0xb0
>>> [<ffffffffb6adc5f4>] do_setlink+0x514/0x11f0
>>> [<ffffffffb6ae4507>] __rtnl_newlink+0x4e7/0xa10
>>> [<ffffffffb6ae4a8c>] rtnl_newlink+0x4c/0x70
>>> [<ffffffffb6adf334>] rtnetlink_rcv_msg+0x184/0x5d0
>>> [<ffffffffb6b6ad1e>] netlink_rcv_skb+0x5e/0x110
>>> [<ffffffffb6ada0e9>] rtnetlink_rcv+0x19/0x20
>>> unreferenced object 0xffff8c1846e16800 (size 256):
>>> comm "ip", pid 7837, jiffies 4295135225 (age 258.160s)
>>> hex dump (first 32 bytes):
>>> 00 20 f7 de 18 8c ff ff 00 00 00 00 00 00 00 00 . ..............
>>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>> backtrace:
>>> [<ffffffffb60fb25c>] slab_post_alloc_hook+0x8c/0x3e0
>>> [<ffffffffb6102b39>] __kmem_cache_alloc_node+0x1d9/0x2a0
>>> [<ffffffffb607684e>] kmalloc_trace+0x2e/0xc0
>>> [<ffffffffb6dbc00b>] vlan_vid_add+0x11b/0x290
>>> [<ffffffffb6dbcffc>] vlan_device_event+0x19c/0x880
>>> [<ffffffffb5dde4d7>] raw_notifier_call_chain+0x47/0x70
>>> [<ffffffffb6ab6940>] call_netdevice_notifiers_info+0x50/0xa0
>>> [<ffffffffb6ac7574>] dev_open+0x94/0xa0
>>> [<ffffffffc177115e>] bond_enslave+0x34e/0x1840 [bonding]
>>
>> This shows that the issue is related to the bond driver, not team.
>
> Now it seems obvious. But I am not that deep into the bond and team drivers
> to tell without your help.
>
>>> [<ffffffffb6ada6b0>] do_set_master+0x90/0xb0
>>> [<ffffffffb6adc5f4>] do_setlink+0x514/0x11f0
>>> [<ffffffffb6ae4507>] __rtnl_newlink+0x4e7/0xa10
>>> [<ffffffffb6ae4a8c>] rtnl_newlink+0x4c/0x70
>>> [<ffffffffb6adf334>] rtnetlink_rcv_msg+0x184/0x5d0
>>> [<ffffffffb6b6ad1e>] netlink_rcv_skb+0x5e/0x110
>>> [<ffffffffb6ada0e9>] rtnetlink_rcv+0x19/0x20
>>> unreferenced object 0xffff8c184c5ff2a0 (size 32):
>>
>> This is 'struct vlan_vid_info'
>>
>>> comm "ip", pid 7837, jiffies 4295135225 (age 258.160s)
>>> hex dump (first 32 bytes):
>>> a0 68 e1 46 18 8c ff ff a0 68 e1 46 18 8c ff ff .h.F.....h.F....
>>> 81 00 00 00 01 00 00 00 cc cc cc cc cc cc cc cc ................
>> ^ VLAN ID 0
>
> This is expert insight. Looks all Greek to me.
>
>>> backtrace:
>>> [<ffffffffb60fb25c>] slab_post_alloc_hook+0x8c/0x3e0
>>> [<ffffffffb6102b39>] __kmem_cache_alloc_node+0x1d9/0x2a0
>>> [<ffffffffb607684e>] kmalloc_trace+0x2e/0xc0
>>> [<ffffffffb6dbc064>] vlan_vid_add+0x174/0x290
>>> [<ffffffffb6dbcffc>] vlan_device_event+0x19c/0x880
>>> [<ffffffffb5dde4d7>] raw_notifier_call_chain+0x47/0x70
>>> [<ffffffffb6ab6940>] call_netdevice_notifiers_info+0x50/0xa0
>>> [<ffffffffb6ac7574>] dev_open+0x94/0xa0
>>> [<ffffffffc177115e>] bond_enslave+0x34e/0x1840 [bonding]
>>> [<ffffffffb6ada6b0>] do_set_master+0x90/0xb0
>>> [<ffffffffb6adc5f4>] do_setlink+0x514/0x11f0
>>> [<ffffffffb6ae4507>] __rtnl_newlink+0x4e7/0xa10
>>> [<ffffffffb6ae4a8c>] rtnl_newlink+0x4c/0x70
>>> [<ffffffffb6adf334>] rtnetlink_rcv_msg+0x184/0x5d0
>>> [<ffffffffb6b6ad1e>] netlink_rcv_skb+0x5e/0x110
>>> [<ffffffffb6ada0e9>] rtnetlink_rcv+0x19/0x20
>>
>> VLAN ID 0 is automatically added by the 8021q driver when a net device
>> is opened. In this case it's a device being enslaved to a bond. I
>> believe the issue was exposed by the new bond test that was added in
>> commit 222c94ec0ad4 ("selftests: bonding: add tests for ether type
>> changes") as part of v6.3-rc3.
>>
>> The VLAN is supposed to be removed by the 8021q driver when a net device
>> is closed and the bond driver indeed calls dev_close() when a slave is
>> removed. However, this function is a NOP when 'IFF_UP' is not set.
>> Unfortunately, when a bond changes its type to Ethernet this flag is
>> incorrectly cleared in bond_ether_setup(), causing this VLAN to linger.
>> As far as I can tell, it's not a new issue.
>>
>> Temporary fix is [1]. Please test it although we might end up with a
>> different fix (needs more thinking and it's already late here).
>
> This fix worked.
>
> In case you submit a formal temporary patch, please add
>
> Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@xxxxxxxxxxxx>
>
> at your convenience.
>
> The issue doesn't seem exploitable without proper privileges, but it is a nice fix
> nevertheless.
>
>> Reproduced using [2]. You can see in the before/after output how the
>> flag is cleared/retained [3].
>>
>> [1]
>> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>> index 236e5219c811..50dc068dc259 100644
>> --- a/drivers/net/bonding/bond_main.c
>> +++ b/drivers/net/bonding/bond_main.c
>> @@ -1777,14 +1777,15 @@ void bond_lower_state_changed(struct slave *slave)
>>
>> /* 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
>> + * have to restore the IFF_MASTER flag, and only restore IFF_SLAVE and IFF_UP
>> + * if they were set
>> */
>> static void bond_ether_setup(struct net_device *bond_dev)
>> {
>> - unsigned int slave_flag = bond_dev->flags & IFF_SLAVE;
>> + unsigned int flags = bond_dev->flags & (IFF_SLAVE | IFF_UP);
>>
>> ether_setup(bond_dev);
>> - bond_dev->flags |= IFF_MASTER | slave_flag;
>> + bond_dev->flags |= IFF_MASTER | flags;
>> bond_dev->priv_flags &= ~IFF_TX_SKB_SHARING;
>> }
>>
>> [2]
>> #!/bin/bash
>>
>> ip link add name t-nlmon type nlmon
>> ip link add name t-dummy type dummy
>> ip link add name t-bond type bond mode active-backup
>>
>> ip link set dev t-bond up
>> ip link set dev t-nlmon master t-bond
>> ip link set dev t-nlmon nomaster
>> ip link show dev t-bond
>> ip link set dev t-dummy master t-bond
>> ip link show dev t-bond
>>
>> ip link del dev t-bond
>> ip link del dev t-dummy
>> ip link del dev t-nlmon
>>
>> [3]
>> Before:
>>
>> 12: t-bond: <NO-CARRIER,BROADCAST,MULTICAST,MASTER,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default qlen 1000
>> link/netlink
>> 12: t-bond: <BROADCAST,MULTICAST,MASTER,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
>> link/ether ce:b2:31:0a:53:83 brd ff:ff:ff:ff:ff:ff
>>
>> After:
>>
>> 12: t-bond: <NO-CARRIER,BROADCAST,MULTICAST,MASTER,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default qlen 1000
>> link/netlink
>> 12: t-bond: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
>> link/ether 5a:18:e7:85:11:73 brd ff:ff:ff:ff:ff:ff
>
> Thank you once again for your patch and your quick response!
>
> Please consider Cc:-ing me for testing the official patch in the original environment.
>
> (Though it is a known HW, there might be BIOS update and fw issues.)

Hi, Ido,

I've ran "make kselftest" with vanilla torvalds tree 6.3-rc5 + your patch.

It failed two lines after "enslaved device client - ns-A IP" which passed OK.

Is this hang for 5 hours in selftests: net: fcnal-test.sh test, at the line
(please see to the end):

# ###########################################################################
# IPv4 address binds
# ###########################################################################
#
#
# #################################################################
# No VRF
#
# SYSCTL: net.ipv4.ping_group_range=0 2147483647
#
# TEST: Raw socket bind to local address - ns-A IP [ OK ]
# TEST: Raw socket bind to local address after device bind - ns-A IP [ OK ]
# TEST: Raw socket bind to local address - ns-A loopback IP [ OK ]
# TEST: Raw socket bind to local address after device bind - ns-A loopback IP [ OK ]
# TEST: Raw socket bind to nonlocal address - nonlocal IP [ OK ]
# TEST: TCP socket bind to nonlocal address - nonlocal IP [ OK ]
# TEST: ICMP socket bind to nonlocal address - nonlocal IP [ OK ]
# TEST: ICMP socket bind to broadcast address - broadcast [ OK ]
# TEST: ICMP socket bind to multicast address - multicast [ OK ]
# TEST: TCP socket bind to local address - ns-A IP [ OK ]
# TEST: TCP socket bind to local address after device bind - ns-A IP [ OK ]
#
# #################################################################
# With VRF
#
# SYSCTL: net.ipv4.ping_group_range=0 2147483647
#
# TEST: Raw socket bind to local address - ns-A IP [ OK ]
# TEST: Raw socket bind to local address after device bind - ns-A IP [ OK ]
# TEST: Raw socket bind to local address after VRF bind - ns-A IP [ OK ]
# TEST: Raw socket bind to local address - VRF IP [ OK ]
# TEST: Raw socket bind to local address after device bind - VRF IP [ OK ]
# TEST: Raw socket bind to local address after VRF bind - VRF IP [ OK ]
# TEST: Raw socket bind to out of scope address after VRF bind - ns-A loopback IP [ OK ]
# TEST: Raw socket bind to nonlocal address after VRF bind - nonlocal IP [ OK ]
# TEST: TCP socket bind to nonlocal address after VRF bind - nonlocal IP [ OK ]
# TEST: ICMP socket bind to nonlocal address after VRF bind - nonlocal IP [ OK ]
# TEST: ICMP socket bind to broadcast address after VRF bind - broadcast [ OK ]
# TEST: ICMP socket bind to multicast address after VRF bind - multicast [ OK ]
# TEST: TCP socket bind to local address - ns-A IP [ OK ]
# TEST: TCP socket bind to local address after device bind - ns-A IP [ OK ]
# TEST: TCP socket bind to local address - VRF IP [ OK ]
# TEST: TCP socket bind to local address after device bind - VRF IP [ OK ]
# TEST: TCP socket bind to invalid local address for VRF - ns-A loopback IP [ OK ]
# TEST: TCP socket bind to invalid local address for device bind - ns-A loopback IP [ OK ]
#
# ###########################################################################
# Run time tests - ipv4
# ###########################################################################
#
# TEST: Device delete with active traffic - ping in - ns-A IP [ OK ]
# TEST: Device delete with active traffic - ping in - VRF IP [ OK ]
# TEST: Device delete with active traffic - ping out - ns-B IP [ OK ]
# TEST: TCP active socket, global server - ns-A IP [ OK ]
# TEST: TCP active socket, global server - VRF IP [ OK ]
# TEST: TCP active socket, VRF server - ns-A IP [ OK ]
# TEST: TCP active socket, VRF server - VRF IP [ OK ]
# TEST: TCP active socket, enslaved device server - ns-A IP [ OK ]
# TEST: TCP active socket, VRF client - ns-A IP [ OK ]
# TEST: TCP active socket, enslaved device client - ns-A IP [ OK ]
# TEST: TCP active socket, global server, VRF client, local - ns-A IP [ OK ]
# TEST: TCP active socket, global server, VRF client, local - VRF IP [ OK ]
# TEST: TCP active socket, VRF server and client, local - ns-A IP [ OK ]
# TEST: TCP active socket, VRF server and client, local - VRF IP [ OK ]
# TEST: TCP active socket, global server, enslaved device client, local - ns-A IP [ OK ]
# TEST: TCP active socket, VRF server, enslaved device client, local - ns-A IP [ OK ]
# TEST: TCP active socket, enslaved device server and client, local - ns-A IP [ OK ]
# TEST: TCP passive socket, global server - ns-A IP [ OK ]
# TEST: TCP passive socket, global server - VRF IP [ OK ]
# TEST: TCP passive socket, VRF server - ns-A IP [ OK ]
# TEST: TCP passive socket, VRF server - VRF IP [ OK ]
# TEST: TCP passive socket, enslaved device server - ns-A IP [ OK ]
# TEST: TCP passive socket, VRF client - ns-A IP [ OK ]
# TEST: TCP passive socket, enslaved device client - ns-A IP [ OK ]
# TEST: TCP passive socket, global server, VRF client, local - ns-A IP [ OK ]

Hope this helps.

I also have a iwlwifi DEADLOCK and I don't know if these should be reported independently.
(I don't think it is related to the patch.)

The iwlwifi team probably has Easter Monday, so there is no rush whatsoever.

I may try to rebuild w/o the patch and re-run the tests, but now I need to do something
for my day job.

No need to thank, this is what kernel testers are for ;-)

Best regards,
Mirsad

--
Mirsad Goran Todorovac
Sistem inženjer
Grafički fakultet | Akademija likovnih umjetnosti
Sveučilište u Zagrebu

System engineer
Faculty of Graphic Arts | Academy of Fine Arts
University of Zagreb, Republic of Croatia
The European Union

"I see something approaching fast ... Will it be friends with me?"

Next message: Srinivas Pandruvada: "[PATCH] thermal: intel: Fix unchecked MSR issue"
Previous message: Sean Christopherson: "Re: [PATCH v4 0/6] KVM: x86: Fix unpermitted XTILE CPUID reporting"
In reply to: Mirsad Goran Todorovac: "Re: [BUG] [FIXED: TESTED] kmemleak in rtnetlink_rcv() triggered by selftests/drivers/net/team in build cdc9718d5e59"
Next in thread: Mirsad Goran Todorovac: "Re: [BUG] [TESTING: HANG] kmemleak in rtnetlink_rcv() triggered by selftests/drivers/net/team in build cdc9718d5e59"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]