[PATCH AUTOSEL 6.6 19/52] net: add netdev_lockdep_set_classes() to virtual drivers

From: Sasha Levin
Date: Fri Mar 29 2024 - 08:53:01 EST

From: Eric Dumazet <edumazet@xxxxxxxxxx>

[ Upstream commit 0bef512012b1cd8820f0c9ec80e5f8ceb43fdd59 ]

Based on a syzbot report, it appears many virtual
drivers do not yet use netdev_lockdep_set_classes(),
triggerring lockdep false positives.

WARNING: possible recursive locking detected
6.8.0-rc4-next-20240212-syzkaller #0 Not tainted

syz-executor.0/19016 is trying to acquire lock:
ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

but task is already holding lock:
ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
lock(_xmit_ETHER#2);
lock(_xmit_ETHER#2);

*** DEADLOCK ***

May be due to missing lock nesting notation

9 locks held by syz-executor.0/19016:
#0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6603
#1: ffffc90000a08c00 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x600 kernel/time/timer.c:1697
#2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
#3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
#3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
#4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
#4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
#4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
#4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325
#5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
#5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
#6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
#7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
#7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
#8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
#8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
#8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
#8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325

stack backtrace:
CPU: 1 PID: 19016 Comm: syz-executor.0 Not tainted 6.8.0-rc4-next-20240212-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
check_deadlock kernel/locking/lockdep.c:3062 [inline]
validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
__lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
__netif_tx_lock include/linux/netdevice.h:4452 [inline]
sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
__dev_xmit_skb net/core/dev.c:3784 [inline]
__dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
neigh_output include/net/neighbour.h:542 [inline]
ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
iptunnel_xmit+0x540/0x9b0 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x20ee/0x2960 net/ipv4/ip_tunnel.c:831
erspan_xmit+0x9de/0x1460 net/ipv4/ip_gre.c:720
__netdev_start_xmit include/linux/netdevice.h:4989 [inline]
netdev_start_xmit include/linux/netdevice.h:5003 [inline]
xmit_one net/core/dev.c:3555 [inline]
dev_hard_start_xmit+0x242/0x770 net/core/dev.c:3571
sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:342
__dev_xmit_skb net/core/dev.c:3784 [inline]
__dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
neigh_output include/net/neighbour.h:542 [inline]
ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
igmpv3_send_cr net/ipv4/igmp.c:723 [inline]
igmp_ifc_timer_expire+0xb71/0xd90 net/ipv4/igmp.c:813
call_timer_fn+0x17e/0x600 kernel/time/timer.c:1700
expire_timers kernel/time/timer.c:1751 [inline]
__run_timers+0x621/0x830 kernel/time/timer.c:2038
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2051
__do_softirq+0x2bc/0x943 kernel/softirq.c:554
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1076 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1076
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:resched_offsets_ok kernel/sched/core.c:10127 [inline]
RIP: 0010:__might_resched+0x16f/0x780 kernel/sched/core.c:10142
Code: 00 4c 89 e8 48 c1 e8 03 48 ba 00 00 00 00 00 fc ff df 48 89 44 24 38 0f b6 04 10 84 c0 0f 85 87 04 00 00 41 8b 45 00 c1 e0 08 <01> d8 44 39 e0 0f 85 d6 00 00 00 44 89 64 24 1c 48 8d bc 24 a0 00
RSP: 0018:ffffc9000ee069e0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8880296a9e00
RDX: dffffc0000000000 RSI: ffff8880296a9e00 RDI: ffffffff8bfe8fa0
RBP: ffffc9000ee06b00 R08: ffffffff82326877 R09: 1ffff11002b5ad1b
R10: dffffc0000000000 R11: ffffed1002b5ad1c R12: 0000000000000000
R13: ffff8880296aa23c R14: 000000000000062a R15: 1ffff92001dc0d44
down_write+0x19/0x50 kernel/locking/rwsem.c:1578
kernfs_activate fs/kernfs/dir.c:1403 [inline]
kernfs_add_one+0x4af/0x8b0 fs/kernfs/dir.c:819
__kernfs_create_file+0x22e/0x2e0 fs/kernfs/file.c:1056
sysfs_add_file_mode_ns+0x24a/0x310 fs/sysfs/file.c:307
create_files fs/sysfs/group.c:64 [inline]
internal_create_group+0x4f4/0xf20 fs/sysfs/group.c:152
internal_create_groups fs/sysfs/group.c:192 [inline]
sysfs_create_groups+0x56/0x120 fs/sysfs/group.c:218
create_dir lib/kobject.c:78 [inline]
kobject_add_internal+0x472/0x8d0 lib/kobject.c:240
kobject_add_varg lib/kobject.c:374 [inline]
kobject_init_and_add+0x124/0x190 lib/kobject.c:457
netdev_queue_add_kobject net/core/net-sysfs.c:1706 [inline]
netdev_queue_update_kobjects+0x1f3/0x480 net/core/net-sysfs.c:1758
register_queue_kobjects net/core/net-sysfs.c:1819 [inline]
netdev_register_kobject+0x265/0x310 net/core/net-sysfs.c:2059
register_netdevice+0x1191/0x19c0 net/core/dev.c:10298
bond_newlink+0x3b/0x90 drivers/net/bonding/bond_netlink.c:576
rtnl_newlink_create net/core/rtnetlink.c:3506 [inline]
__rtnl_newlink net/core/rtnetlink.c:3726 [inline]
rtnl_newlink+0x158f/0x20a0 net/core/rtnetlink.c:3739
rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6606
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
netlink_sendmsg+0xa3c/0xd70 net/netlink/af_netlink.c:1908
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2191
__do_sys_sendto net/socket.c:2203 [inline]
__se_sys_sendto net/socket.c:2199 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2199
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fc3fa87fa9c

Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx>
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240212140700.2795436-4-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/dummy.c | 1 +
drivers/net/geneve.c | 1 +
drivers/net/loopback.c | 1 +
drivers/net/veth.c | 1 +
drivers/net/vxlan/vxlan_core.c | 1 +
net/ipv4/ip_tunnel.c | 1 +
net/ipv6/ip6_gre.c | 2 ++
net/ipv6/ip6_tunnel.c | 1 +
net/ipv6/ip6_vti.c | 1 +
net/ipv6/sit.c | 1 +
10 files changed, 11 insertions(+)

diff --git a/drivers/net/dummy.c b/drivers/net/dummy.c
index c4b1b0aa438ac..5560cf683eb73 100644
--- a/drivers/net/dummy.c
+++ b/drivers/net/dummy.c
@@ -71,6 +71,7 @@ static int dummy_dev_init(struct net_device *dev)
if (!dev->lstats)
return -ENOMEM;

+ netdev_lockdep_set_classes(dev);
return 0;
}

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 78f9d588f7129..3bd10ebeb6c7b 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -335,6 +335,7 @@ static int geneve_init(struct net_device *dev)
gro_cells_destroy(&geneve->gro_cells);
return err;
}
+ netdev_lockdep_set_classes(dev);
return 0;
}

diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index f6d53e63ef4ec..f6eab66c26608 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -144,6 +144,7 @@ static int loopback_dev_init(struct net_device *dev)
dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
if (!dev->lstats)
return -ENOMEM;
+ netdev_lockdep_set_classes(dev);
return 0;
}

diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index 0ae90702e7f84..30982f03847b1 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -1475,6 +1475,7 @@ static void veth_free_queues(struct net_device *dev)

static int veth_dev_init(struct net_device *dev)
{
+ netdev_lockdep_set_classes(dev);
return veth_alloc_queues(dev);
}

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index 5b5597073b004..99ede13124194 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -2960,6 +2960,7 @@ static int vxlan_init(struct net_device *dev)
if (err)
goto err_gro_cells_destroy;

+ netdev_lockdep_set_classes(dev);
return 0;

err_gro_cells_destroy:
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 2d29fce7c5606..55555143646eb 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -1285,6 +1285,7 @@ int ip_tunnel_init(struct net_device *dev)

if (tunnel->collect_md)
netif_keep_dst(dev);
+ netdev_lockdep_set_classes(dev);
return 0;
}
EXPORT_SYMBOL_GPL(ip_tunnel_init);
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 070d87abf7c02..447d244c01b15 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -1511,6 +1511,7 @@ static int ip6gre_tunnel_init_common(struct net_device *dev)
ip6gre_tnl_init_features(dev);

netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
+ netdev_lockdep_set_classes(dev);
return 0;

cleanup_dst_cache_init:
@@ -1903,6 +1904,7 @@ static int ip6erspan_tap_init(struct net_device *dev)
ip6erspan_tnl_link_config(tunnel, 1);

netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
+ netdev_lockdep_set_classes(dev);
return 0;

cleanup_dst_cache_init:
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 9bbabf750a21e..70478027a7af7 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1898,6 +1898,7 @@ ip6_tnl_dev_init_gen(struct net_device *dev)
dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;

netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
+ netdev_lockdep_set_classes(dev);
return 0;

destroy_dst:
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 73c85d4e0e9cd..04e4368fe4655 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -935,6 +935,7 @@ static inline int vti6_dev_init_gen(struct net_device *dev)
if (!dev->tstats)
return -ENOMEM;
netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
+ netdev_lockdep_set_classes(dev);
return 0;
}

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index cc24cefdb85c0..eb4c8e2a2b12e 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -1460,6 +1460,7 @@ static int ipip6_tunnel_init(struct net_device *dev)
return err;
}
netdev_hold(dev, &tunnel->dev_tracker, GFP_KERNEL);
+ netdev_lockdep_set_classes(dev);
return 0;
}

--
2.43.0