Subject: Re: [syzbot] [net?] BUG: sleeping function called from invalid context in synchronize_net

From: syzbot <[email-masked]>
Date: Thu, 11 Jul 2024 14:10:22 -0700

syzbot has found a reproducer for the following issue on:

HEAD commit:    523b23f0bee3 Add linux-next specific files for 20240710
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=11b62585980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce
dashboard link: https://syzkaller.appspot.com/bug?extid=9b277e2c2076e2661f61
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=148611e1980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10ec9585980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/345bcd25ed2f/disk-523b23f0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a4508962d345/vmlinux-523b23f0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4ba5eb555639/bzImage-523b23f0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

BUG: sleeping function called from invalid context at net/core/dev.c:11239
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 1046, name: kworker/u8:5
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
INFO: lockdep is turned off.
CPU: 0 UID: 0 PID: 1046 Comm: kworker/u8:5 Not tainted 6.10.0-rc7-next-20240710-syzkaller #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:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 __might_resched+0x5d4/0x780 kernel/sched/core.c:8526
 synchronize_net+0x1b/0x50 net/core/dev.c:11239
 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:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 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: 1046 at kernel/rcu/tree_plugin.h:330 rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Modules linked in:
CPU: 1 UID: 0 PID: 1046 Comm: kworker/u8:5 Tainted: G        W          6.10.0-rc7-next-20240710-syzkaller #0
Tainted: [W]=WARN
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 bb 02 fe ff 4c 8b b4 24 80 00 00 00 eb 91 c6 05 a4 4f 1f 0e 01 90 48 c7 c7 e0 2d cc 8b e8 ad c5 da 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:ffffc900041cefc0 EFLAGS: 00010046
RAX: 583d87a6c7750500 RBX: ffff88802123de44 RCX: ffff88802123da00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900041cf110 R08: ffffffff815583f2 R09: fffffbfff1c39f8c
R10: dffffc0000000000 R11: fffffbfff1c39f8c R12: ffff88802123da00
R13: 0000000000000000 R14: 1ffff92000839e10 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5b6614bbe3 CR3: 0000000022676000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __schedule+0x348/0x4a60 kernel/sched/core.c:6491
 __schedule_loop kernel/sched/core.c:6680 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6695
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6752
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
 exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:967
 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:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 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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