netdev - [syzbot] [net?] WARNING: suspicious RCU usage in dev_deactivate

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Message-ID: <000000000000c2f7f2061d7bfb12@google.com>
Date: Wed, 17 Jul 2024 19:03:22 -0700
From: syzbot <syzbot+ca9ad1d31885c81155b6@...kaller.appspotmail.com>
To: davem@...emloft.net, edumazet@...gle.com, jhs@...atatu.com, 
	jiri@...nulli.us, kuba@...nel.org, linux-kernel@...r.kernel.org, 
	netdev@...r.kernel.org, pabeni@...hat.com, syzkaller-bugs@...glegroups.com, 
	xiyou.wangcong@...il.com
Subject: [syzbot] [net?] WARNING: suspicious RCU usage in dev_deactivate_queue

Hello,

syzbot found the following issue on:

HEAD commit:    51835949dda3 Merge tag 'net-next-6.11' of git://git.kernel..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=147a6e95980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d3bdd09ea2371c89
dashboard link: https://syzkaller.appspot.com/bug?extid=ca9ad1d31885c81155b6
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=139998b1980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=170b4f31980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/24fbc1342de2/disk-51835949.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/80cd41210088/vmlinux-51835949.xz
kernel image: https://storage.googleapis.com/syzbot-assets/26bfbd59223a/bzImage-51835949.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ca9ad1d31885c81155b6@...kaller.appspotmail.com

=============================
WARNING: suspicious RCU usage
6.10.0-syzkaller-04472-g51835949dda3 #0 Not tainted
-----------------------------
net/sched/sch_generic.c:1284 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by kworker/u8:11/2874:
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:327 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:839 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: bond_mii_monitor+0x174/0x3170 drivers/net/bonding/bond_main.c:2824

stack backtrace:
CPU: 0 PID: 2874 Comm: kworker/u8:11 Not tainted 6.10.0-syzkaller-04472-g51835949dda3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6711
 dev_deactivate_queue+0x8f/0x160 net/sched/sch_generic.c:1284
 netdev_for_each_tx_queue include/linux/netdevice.h:2513 [inline]
 dev_deactivate_many+0xc8/0xb10 net/sched/sch_generic.c:1357
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

=============================
WARNING: suspicious RCU usage
6.10.0-syzkaller-04472-g51835949dda3 #0 Not tainted
-----------------------------
include/linux/rtnetlink.h:100 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by kworker/u8:11/2874:
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:327 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:839 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: bond_mii_monitor+0x174/0x3170 drivers/net/bonding/bond_main.c:2824

stack backtrace:
CPU: 1 PID: 2874 Comm: kworker/u8:11 Not tainted 6.10.0-syzkaller-04472-g51835949dda3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6711
 dev_ingress_queue include/linux/rtnetlink.h:100 [inline]
 dev_deactivate_many+0x18f/0xb10 net/sched/sch_generic.c:1359
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
BUG: sleeping function called from invalid context at net/core/dev.c:11221
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 2874, name: kworker/u8:11
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
3 locks held by kworker/u8:11/2874:
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:327 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:839 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: bond_mii_monitor+0x174/0x3170 drivers/net/bonding/bond_main.c:2824
CPU: 1 PID: 2874 Comm: kworker/u8:11 Not tainted 6.10.0-syzkaller-04472-g51835949dda3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 __might_resched+0x5d4/0x780 kernel/sched/core.c:8437
 synchronize_net+0x1b/0x50 net/core/dev.c:11221
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

=============================
WARNING: suspicious RCU usage
6.10.0-syzkaller-04472-g51835949dda3 #0 Tainted: G        W         
-----------------------------
kernel/rcu/tree_exp.h:931 Illegal synchronize_rcu_expedited() in RCU read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by kworker/u8:11/2874:
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:327 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:839 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: bond_mii_monitor+0x174/0x3170 drivers/net/bonding/bond_main.c:2824

stack backtrace:
CPU: 1 PID: 2874 Comm: kworker/u8:11 Tainted: G        W          6.10.0-syzkaller-04472-g51835949dda3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6711
 synchronize_rcu_expedited+0x12e/0x830 kernel/rcu/tree_exp.h:928
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

=============================
[ BUG: Invalid wait context ]
6.10.0-syzkaller-04472-g51835949dda3 #0 Tainted: G        W         
-----------------------------
kworker/u8:11/2874 is trying to lock:
ffffffff8e33b3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline]
ffffffff8e33b3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958
other info that might help us debug this:
context-{4:4}
3 locks held by kworker/u8:11/2874:
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff888023286148 ((wq_completion)bond0){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90009dc7d00 ((work_completion)(&(&bond->mii_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:327 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:839 [inline]
 #2: ffffffff8e335fe0 (rcu_read_lock){....}-{1:2}, at: bond_mii_monitor+0x174/0x3170 drivers/net/bonding/bond_main.c:2824
stack backtrace:
CPU: 1 PID: 2874 Comm: kworker/u8:11 Tainted: G        W          6.10.0-syzkaller-04472-g51835949dda3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 print_lock_invalid_wait_context kernel/locking/lockdep.c:4750 [inline]
 check_wait_context kernel/locking/lockdep.c:4820 [inline]
 __lock_acquire+0x1507/0x1fd0 kernel/locking/lockdep.c:5086
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5753
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline]
 synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
------------[ cut here ]------------
Voluntary context switch within RCU read-side critical section!
WARNING: CPU: 1 PID: 2874 at kernel/rcu/tree_plugin.h:330 rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Modules linked in:
CPU: 1 PID: 2874 Comm: kworker/u8:11 Tainted: G        W          6.10.0-syzkaller-04472-g51835949dda3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
RIP: 0010:rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Code: 00 ba 02 00 00 00 e8 cb 02 fe ff 4c 8b b4 24 80 00 00 00 eb 91 c6 05 98 3f 1b 0e 01 90 48 c7 c7 40 21 cc 8b e8 8d 26 db ff 90 <0f> 0b 90 90 e9 3b f4 ff ff 90 0f 0b 90 45 84 ed 0f 84 00 f4 ff ff
RSP: 0018:ffffc90009dc6fc0 EFLAGS: 00010046
RAX: 129439ac0980bb00 RBX: ffff88802b6c8444 RCX: ffff88802b6c8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90009dc7110 R08: ffffffff815878a2 R09: fffffbfff1c39d94
R10: dffffc0000000000 R11: fffffbfff1c39d94 R12: ffff88802b6c8000
R13: 0000000000000000 R14: 1ffff920013b8e10 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563178d9e028 CR3: 000000000e134000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __schedule+0x348/0x4a60 kernel/sched/core.c:6417
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678
 mutex_optimistic_spin kernel/locking/mutex.c:510 [inline]
 __mutex_lock_common kernel/locking/mutex.c:612 [inline]
 __mutex_lock+0x391/0xd70 kernel/locking/mutex.c:752
 exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline]
 synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>


---
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