linux-stable.git/drivers/net/bonding, branch v5.14.2 Linux kernel stable tree bonding: fix build issue 2021-07-17T00:22:35+00:00 Mahesh Bandewar maheshb@google.com 2021-07-16T23:09:41+00:00 5b69874f74cc5707edd95fcdaa757c507ac8af0f The commit 9a5605505d9c (" bonding: Add struct bond_ipesc to manage SA") is causing following build error when XFRM is not selected in kernel config. lld: error: undefined symbol: xfrm_dev_state_flush >>> referenced by bond_main.c:3453 (drivers/net/bonding/bond_main.c:3453) >>> net/bonding/bond_main.o:(bond_netdev_event) in archive drivers/built-in.a Fixes: 9a5605505d9c (" bonding: Add struct bond_ipesc to manage SA") Signed-off-by: Mahesh Bandewar <maheshb@google.com> CC: Taehee Yoo <ap420073@gmail.com> CC: Jay Vosburgh <jay.vosburgh@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
The commit 9a5605505d9c (" bonding: Add struct bond_ipesc to manage SA") is causing
following build error when XFRM is not selected in kernel config.

lld: error: undefined symbol: xfrm_dev_state_flush
>>> referenced by bond_main.c:3453 (drivers/net/bonding/bond_main.c:3453)
>>>               net/bonding/bond_main.o:(bond_netdev_event) in archive drivers/built-in.a

Fixes: 9a5605505d9c (" bonding: Add struct bond_ipesc to manage SA")
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
CC: Taehee Yoo <ap420073@gmail.com>
CC: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bonding: fix incorrect return value of bond_ipsec_offload_ok() 2021-07-06T17:36:59+00:00 Taehee Yoo ap420073@gmail.com 2021-07-05T15:38:14+00:00 168e696a36792a4a3b2525a06249e7472ef90186 bond_ipsec_offload_ok() is called to check whether the interface supports ipsec offload or not. bonding interface support ipsec offload only in active-backup mode. So, if a bond interface is not in active-backup mode, it should return false but it returns true. Fixes: a3b658cfb664 ("bonding: allow xfrm offload setup post-module-load") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
bond_ipsec_offload_ok() is called to check whether the interface supports
ipsec offload or not.
bonding interface support ipsec offload only in active-backup mode.
So, if a bond interface is not in active-backup mode, it should return
false but it returns true.

Fixes: a3b658cfb664 ("bonding: allow xfrm offload setup post-module-load")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bonding: fix suspicious RCU usage in bond_ipsec_offload_ok() 2021-07-06T17:36:59+00:00 Taehee Yoo ap420073@gmail.com 2021-07-05T15:38:13+00:00 955b785ec6b3b2f9b91914d6eeac8ee66ee29239 To dereference bond->curr_active_slave, it uses rcu_dereference(). But it and the caller doesn't acquire RCU so a warning occurs. So add rcu_read_lock(). Splat looks like: WARNING: suspicious RCU usage 5.13.0-rc6+ #1179 Not tainted drivers/net/bonding/bond_main.c:571 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ping/974: #0: ffff888109e7db70 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x1303/0x2cb0 stack backtrace: CPU: 2 PID: 974 Comm: ping Not tainted 5.13.0-rc6+ #1179 Call Trace: dump_stack+0xa4/0xe5 bond_ipsec_offload_ok+0x1f4/0x260 [bonding] xfrm_output+0x179/0x890 xfrm4_output+0xfa/0x410 ? __xfrm4_output+0x4b0/0x4b0 ? __ip_make_skb+0xecc/0x2030 ? xfrm4_udp_encap_rcv+0x800/0x800 ? ip_local_out+0x21/0x3a0 ip_send_skb+0x37/0xa0 raw_sendmsg+0x1bfd/0x2cb0 Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
To dereference bond->curr_active_slave, it uses rcu_dereference().
But it and the caller doesn't acquire RCU so a warning occurs.
So add rcu_read_lock().

Splat looks like:
WARNING: suspicious RCU usage
5.13.0-rc6+ #1179 Not tainted
drivers/net/bonding/bond_main.c:571 suspicious
rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by ping/974:
 #0: ffff888109e7db70 (sk_lock-AF_INET){+.+.}-{0:0},
at: raw_sendmsg+0x1303/0x2cb0

stack backtrace:
CPU: 2 PID: 974 Comm: ping Not tainted 5.13.0-rc6+ #1179
Call Trace:
 dump_stack+0xa4/0xe5
 bond_ipsec_offload_ok+0x1f4/0x260 [bonding]
 xfrm_output+0x179/0x890
 xfrm4_output+0xfa/0x410
 ? __xfrm4_output+0x4b0/0x4b0
 ? __ip_make_skb+0xecc/0x2030
 ? xfrm4_udp_encap_rcv+0x800/0x800
 ? ip_local_out+0x21/0x3a0
 ip_send_skb+0x37/0xa0
 raw_sendmsg+0x1bfd/0x2cb0

Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bonding: Add struct bond_ipesc to manage SA 2021-07-06T17:36:59+00:00 Taehee Yoo ap420073@gmail.com 2021-07-05T15:38:12+00:00 9a5605505d9c7dbfdb89cc29a8f5fc5cf9fd2334 bonding has been supporting ipsec offload. When SA is added, bonding just passes SA to its own active real interface. But it doesn't manage SA. So, when events(add/del real interface, active real interface change, etc) occur, bonding can't handle that well because It doesn't manage SA. So some problems(panic, UAF, refcnt leak)occur. In order to make it stable, it should manage SA. That's the reason why struct bond_ipsec is added. When a new SA is added to bonding interface, it is stored in the bond_ipsec list. And the SA is passed to a current active real interface. If events occur, it uses bond_ipsec data to handle these events. bond->ipsec_list is protected by bond->ipsec_lock. If a current active real interface is changed, the following logic works. 1. delete all SAs from old active real interface 2. Add all SAs to the new active real interface. 3. If a new active real interface doesn't support ipsec offload or SA's option, it sets real_dev to NULL. Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
bonding has been supporting ipsec offload.
When SA is added, bonding just passes SA to its own active real interface.
But it doesn't manage SA.
So, when events(add/del real interface, active real interface change, etc)
occur, bonding can't handle that well because It doesn't manage SA.
So some problems(panic, UAF, refcnt leak)occur.

In order to make it stable, it should manage SA.
That's the reason why struct bond_ipsec is added.
When a new SA is added to bonding interface, it is stored in the
bond_ipsec list. And the SA is passed to a current active real interface.
If events occur, it uses bond_ipsec data to handle these events.
bond->ipsec_list is protected by bond->ipsec_lock.

If a current active real interface is changed, the following logic works.
1. delete all SAs from old active real interface
2. Add all SAs to the new active real interface.
3. If a new active real interface doesn't support ipsec offload or SA's
option, it sets real_dev to NULL.

Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bonding: disallow setting nested bonding + ipsec offload 2021-07-06T17:36:59+00:00 Taehee Yoo ap420073@gmail.com 2021-07-05T15:38:11+00:00 b121693381b112b78c076dea171ee113e237c0e4 bonding interface can be nested and it supports ipsec offload. So, it allows setting the nested bonding + ipsec scenario. But code does not support this scenario. So, it should be disallowed. interface graph: bond2 | bond1 | eth0 The nested bonding + ipsec offload may not a real usecase. So, disallowing this scenario is fine. Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
bonding interface can be nested and it supports ipsec offload.
So, it allows setting the nested bonding + ipsec scenario.
But code does not support this scenario.
So, it should be disallowed.

interface graph:
bond2
   |
bond1
   |
eth0

The nested bonding + ipsec offload may not a real usecase.
So, disallowing this scenario is fine.

Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bonding: fix suspicious RCU usage in bond_ipsec_del_sa() 2021-07-06T17:36:59+00:00 Taehee Yoo ap420073@gmail.com 2021-07-05T15:38:10+00:00 a22c39b831a081da9b2c488bd970a4412d926f30 To dereference bond->curr_active_slave, it uses rcu_dereference(). But it and the caller doesn't acquire RCU so a warning occurs. So add rcu_read_lock(). Test commands: ip netns add A ip netns exec A bash modprobe netdevsim echo "1 1" > /sys/bus/netdevsim/new_device ip link add bond0 type bond ip link set eth0 master bond0 ip link set eth0 up ip link set bond0 up ip x s add proto esp dst 14.1.1.1 src 15.1.1.1 spi 0x07 mode \ transport reqid 0x07 replay-window 32 aead 'rfc4106(gcm(aes))' \ 0x44434241343332312423222114131211f4f3f2f1 128 sel src 14.0.0.52/24 \ dst 14.0.0.70/24 proto tcp offload dev bond0 dir in ip x s f Splat looks like: ============================= WARNING: suspicious RCU usage 5.13.0-rc3+ #1168 Not tainted ----------------------------- drivers/net/bonding/bond_main.c:448 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by ip/705: #0: ffff888106701780 (&net->xfrm.xfrm_cfg_mutex){+.+.}-{3:3}, at: xfrm_netlink_rcv+0x59/0x80 [xfrm_user] #1: ffff8880075b0098 (&x->lock){+.-.}-{2:2}, at: xfrm_state_delete+0x16/0x30 stack backtrace: CPU: 6 PID: 705 Comm: ip Not tainted 5.13.0-rc3+ #1168 Call Trace: dump_stack+0xa4/0xe5 bond_ipsec_del_sa+0x16a/0x1c0 [bonding] __xfrm_state_delete+0x51f/0x730 xfrm_state_delete+0x1e/0x30 xfrm_state_flush+0x22f/0x390 xfrm_flush_sa+0xd8/0x260 [xfrm_user] ? xfrm_flush_policy+0x290/0x290 [xfrm_user] xfrm_user_rcv_msg+0x331/0x660 [xfrm_user] ? rcu_read_lock_sched_held+0x91/0xc0 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user] ? find_held_lock+0x3a/0x1c0 ? mutex_lock_io_nested+0x1210/0x1210 ? sched_clock_cpu+0x18/0x170 netlink_rcv_skb+0x121/0x350 [ ... ] Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
To dereference bond->curr_active_slave, it uses rcu_dereference().
But it and the caller doesn't acquire RCU so a warning occurs.
So add rcu_read_lock().

Test commands:
    ip netns add A
    ip netns exec A bash
    modprobe netdevsim
    echo "1 1" > /sys/bus/netdevsim/new_device
    ip link add bond0 type bond
    ip link set eth0 master bond0
    ip link set eth0 up
    ip link set bond0 up
    ip x s add proto esp dst 14.1.1.1 src 15.1.1.1 spi 0x07 mode \
transport reqid 0x07 replay-window 32 aead 'rfc4106(gcm(aes))' \
0x44434241343332312423222114131211f4f3f2f1 128 sel src 14.0.0.52/24 \
dst 14.0.0.70/24 proto tcp offload dev bond0 dir in
    ip x s f

Splat looks like:
=============================
WARNING: suspicious RCU usage
5.13.0-rc3+ #1168 Not tainted
-----------------------------
drivers/net/bonding/bond_main.c:448 suspicious rcu_dereference_check()
usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
2 locks held by ip/705:
 #0: ffff888106701780 (&net->xfrm.xfrm_cfg_mutex){+.+.}-{3:3},
at: xfrm_netlink_rcv+0x59/0x80 [xfrm_user]
 #1: ffff8880075b0098 (&x->lock){+.-.}-{2:2},
at: xfrm_state_delete+0x16/0x30

stack backtrace:
CPU: 6 PID: 705 Comm: ip Not tainted 5.13.0-rc3+ #1168
Call Trace:
 dump_stack+0xa4/0xe5
 bond_ipsec_del_sa+0x16a/0x1c0 [bonding]
 __xfrm_state_delete+0x51f/0x730
 xfrm_state_delete+0x1e/0x30
 xfrm_state_flush+0x22f/0x390
 xfrm_flush_sa+0xd8/0x260 [xfrm_user]
 ? xfrm_flush_policy+0x290/0x290 [xfrm_user]
 xfrm_user_rcv_msg+0x331/0x660 [xfrm_user]
 ? rcu_read_lock_sched_held+0x91/0xc0
 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user]
 ? find_held_lock+0x3a/0x1c0
 ? mutex_lock_io_nested+0x1210/0x1210
 ? sched_clock_cpu+0x18/0x170
 netlink_rcv_skb+0x121/0x350
[ ... ]

Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bonding: fix null dereference in bond_ipsec_add_sa() 2021-07-06T17:36:59+00:00 Taehee Yoo ap420073@gmail.com 2021-07-05T15:38:07+00:00 105cd17a866017b45f3c45901b394c711c97bf40 If bond doesn't have real device, bond->curr_active_slave is null. But bond_ipsec_add_sa() dereferences bond->curr_active_slave without null checking. So, null-ptr-deref would occur. Test commands: ip link add bond0 type bond ip link set bond0 up ip x s add proto esp dst 14.1.1.1 src 15.1.1.1 spi \ 0x07 mode transport reqid 0x07 replay-window 32 aead 'rfc4106(gcm(aes))' \ 0x44434241343332312423222114131211f4f3f2f1 128 sel src 14.0.0.52/24 \ dst 14.0.0.70/24 proto tcp offload dev bond0 dir in Splat looks like: KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 4 PID: 680 Comm: ip Not tainted 5.13.0-rc3+ #1168 RIP: 0010:bond_ipsec_add_sa+0xc4/0x2e0 [bonding] Code: 85 21 02 00 00 4d 8b a6 48 0c 00 00 e8 75 58 44 ce 85 c0 0f 85 14 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 fc 01 00 00 48 8d bb e0 02 00 00 4d 8b 2c 24 48 RSP: 0018:ffff88810946f508 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88810b4e8040 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8fe34280 RDI: ffff888115abe100 RBP: ffff88810946f528 R08: 0000000000000003 R09: fffffbfff2287e11 R10: 0000000000000001 R11: ffff888115abe0c8 R12: 0000000000000000 R13: ffffffffc0aea9a0 R14: ffff88800d7d2000 R15: ffff88810b4e8330 FS: 00007efc5552e680(0000) GS:ffff888119c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c2530dbf40 CR3: 0000000103056004 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: xfrm_dev_state_add+0x2a9/0x770 ? memcpy+0x38/0x60 xfrm_add_sa+0x2278/0x3b10 [xfrm_user] ? xfrm_get_policy+0xaa0/0xaa0 [xfrm_user] ? register_lock_class+0x1750/0x1750 xfrm_user_rcv_msg+0x331/0x660 [xfrm_user] ? rcu_read_lock_sched_held+0x91/0xc0 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user] ? find_held_lock+0x3a/0x1c0 ? mutex_lock_io_nested+0x1210/0x1210 ? sched_clock_cpu+0x18/0x170 netlink_rcv_skb+0x121/0x350 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user] ? netlink_ack+0x9d0/0x9d0 ? netlink_deliver_tap+0x17c/0xa50 xfrm_netlink_rcv+0x68/0x80 [xfrm_user] netlink_unicast+0x41c/0x610 ? netlink_attachskb+0x710/0x710 netlink_sendmsg+0x6b9/0xb70 [ ...] Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
If bond doesn't have real device, bond->curr_active_slave is null.
But bond_ipsec_add_sa() dereferences bond->curr_active_slave without
null checking.
So, null-ptr-deref would occur.

Test commands:
    ip link add bond0 type bond
    ip link set bond0 up
    ip x s add proto esp dst 14.1.1.1 src 15.1.1.1 spi \
0x07 mode transport reqid 0x07 replay-window 32 aead 'rfc4106(gcm(aes))' \
0x44434241343332312423222114131211f4f3f2f1 128 sel src 14.0.0.52/24 \
dst 14.0.0.70/24 proto tcp offload dev bond0 dir in

Splat looks like:
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 4 PID: 680 Comm: ip Not tainted 5.13.0-rc3+ #1168
RIP: 0010:bond_ipsec_add_sa+0xc4/0x2e0 [bonding]
Code: 85 21 02 00 00 4d 8b a6 48 0c 00 00 e8 75 58 44 ce 85 c0 0f 85 14
01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02
00 0f 85 fc 01 00 00 48 8d bb e0 02 00 00 4d 8b 2c 24 48
RSP: 0018:ffff88810946f508 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88810b4e8040 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8fe34280 RDI: ffff888115abe100
RBP: ffff88810946f528 R08: 0000000000000003 R09: fffffbfff2287e11
R10: 0000000000000001 R11: ffff888115abe0c8 R12: 0000000000000000
R13: ffffffffc0aea9a0 R14: ffff88800d7d2000 R15: ffff88810b4e8330
FS:  00007efc5552e680(0000) GS:ffff888119c00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c2530dbf40 CR3: 0000000103056004 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 xfrm_dev_state_add+0x2a9/0x770
 ? memcpy+0x38/0x60
 xfrm_add_sa+0x2278/0x3b10 [xfrm_user]
 ? xfrm_get_policy+0xaa0/0xaa0 [xfrm_user]
 ? register_lock_class+0x1750/0x1750
 xfrm_user_rcv_msg+0x331/0x660 [xfrm_user]
 ? rcu_read_lock_sched_held+0x91/0xc0
 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user]
 ? find_held_lock+0x3a/0x1c0
 ? mutex_lock_io_nested+0x1210/0x1210
 ? sched_clock_cpu+0x18/0x170
 netlink_rcv_skb+0x121/0x350
 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user]
 ? netlink_ack+0x9d0/0x9d0
 ? netlink_deliver_tap+0x17c/0xa50
 xfrm_netlink_rcv+0x68/0x80 [xfrm_user]
 netlink_unicast+0x41c/0x610
 ? netlink_attachskb+0x710/0x710
 netlink_sendmsg+0x6b9/0xb70
[ ...]

Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bonding: fix suspicious RCU usage in bond_ipsec_add_sa() 2021-07-06T17:36:59+00:00 Taehee Yoo ap420073@gmail.com 2021-07-05T15:38:06+00:00 b648eba4c69e5819880b4907e7fcb2bb576069ab To dereference bond->curr_active_slave, it uses rcu_dereference(). But it and the caller doesn't acquire RCU so a warning occurs. So add rcu_read_lock(). Test commands: ip link add dummy0 type dummy ip link add bond0 type bond ip link set dummy0 master bond0 ip link set dummy0 up ip link set bond0 up ip x s add proto esp dst 14.1.1.1 src 15.1.1.1 spi 0x07 \ mode transport \ reqid 0x07 replay-window 32 aead 'rfc4106(gcm(aes))' \ 0x44434241343332312423222114131211f4f3f2f1 128 sel \ src 14.0.0.52/24 dst 14.0.0.70/24 proto tcp offload \ dev bond0 dir in Splat looks like: ============================= WARNING: suspicious RCU usage 5.13.0-rc3+ #1168 Not tainted ----------------------------- drivers/net/bonding/bond_main.c:411 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/684: #0: ffffffff9a2757c0 (&net->xfrm.xfrm_cfg_mutex){+.+.}-{3:3}, at: xfrm_netlink_rcv+0x59/0x80 [xfrm_user] 55.191733][ T684] stack backtrace: CPU: 0 PID: 684 Comm: ip Not tainted 5.13.0-rc3+ #1168 Call Trace: dump_stack+0xa4/0xe5 bond_ipsec_add_sa+0x18c/0x1f0 [bonding] xfrm_dev_state_add+0x2a9/0x770 ? memcpy+0x38/0x60 xfrm_add_sa+0x2278/0x3b10 [xfrm_user] ? xfrm_get_policy+0xaa0/0xaa0 [xfrm_user] ? register_lock_class+0x1750/0x1750 xfrm_user_rcv_msg+0x331/0x660 [xfrm_user] ? rcu_read_lock_sched_held+0x91/0xc0 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user] ? find_held_lock+0x3a/0x1c0 ? mutex_lock_io_nested+0x1210/0x1210 ? sched_clock_cpu+0x18/0x170 netlink_rcv_skb+0x121/0x350 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user] ? netlink_ack+0x9d0/0x9d0 ? netlink_deliver_tap+0x17c/0xa50 xfrm_netlink_rcv+0x68/0x80 [xfrm_user] netlink_unicast+0x41c/0x610 ? netlink_attachskb+0x710/0x710 netlink_sendmsg+0x6b9/0xb70 [ ... ] Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
To dereference bond->curr_active_slave, it uses rcu_dereference().
But it and the caller doesn't acquire RCU so a warning occurs.
So add rcu_read_lock().

Test commands:
    ip link add dummy0 type dummy
    ip link add bond0 type bond
    ip link set dummy0 master bond0
    ip link set dummy0 up
    ip link set bond0 up
    ip x s add proto esp dst 14.1.1.1 src 15.1.1.1 spi 0x07 \
	    mode transport \
	    reqid 0x07 replay-window 32 aead 'rfc4106(gcm(aes))' \
	    0x44434241343332312423222114131211f4f3f2f1 128 sel \
	    src 14.0.0.52/24 dst 14.0.0.70/24 proto tcp offload \
	    dev bond0 dir in

Splat looks like:
=============================
WARNING: suspicious RCU usage
5.13.0-rc3+ #1168 Not tainted
-----------------------------
drivers/net/bonding/bond_main.c:411 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by ip/684:
 #0: ffffffff9a2757c0 (&net->xfrm.xfrm_cfg_mutex){+.+.}-{3:3},
at: xfrm_netlink_rcv+0x59/0x80 [xfrm_user]
   55.191733][  T684] stack backtrace:
CPU: 0 PID: 684 Comm: ip Not tainted 5.13.0-rc3+ #1168
Call Trace:
 dump_stack+0xa4/0xe5
 bond_ipsec_add_sa+0x18c/0x1f0 [bonding]
 xfrm_dev_state_add+0x2a9/0x770
 ? memcpy+0x38/0x60
 xfrm_add_sa+0x2278/0x3b10 [xfrm_user]
 ? xfrm_get_policy+0xaa0/0xaa0 [xfrm_user]
 ? register_lock_class+0x1750/0x1750
 xfrm_user_rcv_msg+0x331/0x660 [xfrm_user]
 ? rcu_read_lock_sched_held+0x91/0xc0
 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user]
 ? find_held_lock+0x3a/0x1c0
 ? mutex_lock_io_nested+0x1210/0x1210
 ? sched_clock_cpu+0x18/0x170
 netlink_rcv_skb+0x121/0x350
 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user]
 ? netlink_ack+0x9d0/0x9d0
 ? netlink_deliver_tap+0x17c/0xa50
 xfrm_netlink_rcv+0x68/0x80 [xfrm_user]
 netlink_unicast+0x41c/0x610
 ? netlink_attachskb+0x710/0x710
 netlink_sendmsg+0x6b9/0xb70
[ ... ]

Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-06-29T22:45:27+00:00 Jakub Kicinski kuba@kernel.org 2021-06-29T22:45:27+00:00 b6df00789e2831fff7a2c65aa7164b2a4dcbe599 Trivial conflict in net/netfilter/nf_tables_api.c. Duplicate fix in tools/testing/selftests/net/devlink_port_split.py - take the net-next version. skmsg, and L4 bpf - keep the bpf code but remove the flags and err params. Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Trivial conflict in net/netfilter/nf_tables_api.c.

Duplicate fix in tools/testing/selftests/net/devlink_port_split.py
- take the net-next version.

skmsg, and L4 bpf - keep the bpf code but remove the flags
and err params.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
bonding: allow nesting of bonding device 2021-06-23T20:43:44+00:00 Di Zhu zhudi21@huawei.com 2021-06-23T03:21:08+00:00 4d293fe1c69c157c15ac06918a805e5fef036682 The commit 3c9ef511b9fa ("bonding: avoid adding slave device with IFF_MASTER flag") fix a crash when add slave device with IFF_MASTER, but it rejects the scenario of nested bonding device. As Eric Dumazet described: since there indeed is a usage scenario about nesting bonding, we should not break it. So we add a new judgment condition to allow nesting of bonding device. Fixes: 3c9ef511b9fa ("bonding: avoid adding slave device with IFF_MASTER flag") Suggested-by: Jay Vosburgh <jay.vosburgh@canonical.com> Signed-off-by: Di Zhu <zhudi21@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
The commit 3c9ef511b9fa ("bonding: avoid adding slave device with
IFF_MASTER flag") fix a crash when add slave device with IFF_MASTER,
but it rejects the scenario of nested bonding device.

As Eric Dumazet described: since there indeed is a usage scenario about
nesting bonding, we should not break it.

So we add a new judgment condition to allow nesting of bonding device.

Fixes: 3c9ef511b9fa ("bonding: avoid adding slave device with IFF_MASTER flag")
Suggested-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Di Zhu <zhudi21@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>