syzbot
possible deadlock in ppp_input
Status:
auto-obsoleted due to no activity on 2024/12/25 23:46
Reported-by: syzbot+32f622ecfda20eccd42d@syzkaller.appspotmail.com
First crash: 700d, last: 667d
Sample crash report:
=====================================================
WARNING: SOFTIRQ-READ-safe -> SOFTIRQ-READ-unsafe lock order detected
5.15.167-syzkaller #0 Not tainted
-----------------------------------------------------
syz.3.652/7412 [HC0[0]:SC0[8]:HE1:SE0] is trying to acquire:
ffff8880750b91e0 (&pch->downl){+.+.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline]
ffff8880750b91e0 (&pch->downl){+.+.}-{2:2}, at: ppp_connect_channel+0x190/0x640 drivers/net/ppp/ppp_generic.c:3484
and this task is already holding:
ffff888077558dd0 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline]
ffff888077558dd0 (&ppp->rlock){+...}-{2:2}, at: ppp_connect_channel+0x181/0x640 drivers/net/ppp/ppp_generic.c:3483
which would create a new lock dependency:
(&ppp->rlock){+...}-{2:2} -> (&pch->downl){+.+.}-{2:2}
but this new dependency connects a SOFTIRQ-READ-irq-safe lock:
(&pch->upl){++.-}-{2:2}
... which became SOFTIRQ-READ-irq-safe at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline]
_raw_read_lock_bh+0x39/0x50 kernel/locking/spinlock.c:252
ppp_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306
ppp_async_process+0x7b/0x140 drivers/net/ppp/ppp_async.c:505
tasklet_action_common+0x3cb/0x4a0
handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
__do_softirq kernel/softirq.c:592 [inline]
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
sysvec_call_function_single+0x8e/0xb0 arch/x86/kernel/smp.c:243
asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:646
preempt_schedule_irq+0xf2/0x1c0 kernel/sched/core.c:6777
irqentry_exit+0x53/0x80 kernel/entry/common.c:432
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643
__tasklet_schedule_common+0x1f9/0x260 kernel/softirq.c:737
tasklet_schedule include/linux/interrupt.h:657 [inline]
ppp_asynctty_receive+0x1ea2/0x2000 drivers/net/ppp/ppp_async.c:354
tty_ldisc_receive_buf+0x121/0x160 drivers/tty/tty_buffer.c:455
tty_port_default_receive_buf+0x6a/0x90 drivers/tty/tty_port.c:39
receive_buf drivers/tty/tty_buffer.c:471 [inline]
flush_to_ldisc+0x2b9/0x540 drivers/tty/tty_buffer.c:523
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
to a SOFTIRQ-READ-irq-unsafe lock:
(&pch->downl){+.+.}-{2:2}
... which became SOFTIRQ-READ-irq-unsafe at:
...
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:363 [inline]
ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2271 [inline]
ppp_input+0x160/0x980 drivers/net/ppp/ppp_generic.c:2303
pppoe_rcv_core+0x109/0x2f0 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv include/net/sock.h:1059 [inline]
__release_sock+0x198/0x4b0 net/core/sock.c:2724
release_sock+0x5d/0x1c0 net/core/sock.c:3265
pppoe_sendmsg+0xd1/0x740 drivers/net/ppp/pppoe.c:903
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
__sys_sendmmsg+0x2bf/0x560 net/socket.c:2571
__do_sys_sendmmsg net/socket.c:2600 [inline]
__se_sys_sendmmsg net/socket.c:2597 [inline]
__x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2597
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
other info that might help us debug this:
Chain exists of:
&pch->upl --> &ppp->rlock --> &pch->downl
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&pch->downl);
local_irq_disable();
lock(&pch->upl);
lock(&ppp->rlock);
<Interrupt>
lock(&pch->upl);
*** DEADLOCK ***
5 locks held by syz.3.652/7412:
#0: ffffffff8d2c7a48 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x10e/0x1cd0 drivers/net/ppp/ppp_generic.c:726
#1: ffff888027df44c0 (&pn->all_ppp_mutex){+.+.}-{3:3}, at: ppp_connect_channel+0x5e/0x640 drivers/net/ppp/ppp_generic.c:3473
#2: ffff8880750b9240 (&pch->upl){++.-}-{2:2}, at: ppp_connect_channel+0x87/0x640 drivers/net/ppp/ppp_generic.c:3477
#3: ffff888077558e10 (&ppp->wlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline]
#3: ffff888077558e10 (&ppp->wlock){+...}-{2:2}, at: ppp_connect_channel+0x170/0x640 drivers/net/ppp/ppp_generic.c:3483
#4: ffff888077558dd0 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline]
#4: ffff888077558dd0 (&ppp->rlock){+...}-{2:2}, at: ppp_connect_channel+0x181/0x640 drivers/net/ppp/ppp_generic.c:3483
the dependencies between SOFTIRQ-READ-irq-safe lock and the holding lock:
-> (&pch->upl){++.-}-{2:2} {
HARDIRQ-ON-W at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline]
_raw_write_lock_bh+0x31/0x40 kernel/locking/spinlock.c:324
ppp_disconnect_channel+0x2f/0x2d0 drivers/net/ppp/ppp_generic.c:3521
ppp_unregister_channel+0xb5/0x2f0 drivers/net/ppp/ppp_generic.c:2995
pppox_unbind_sock+0x58/0xa0 drivers/net/ppp/pppox.c:58
pppoe_release+0x158/0x800 drivers/net/ppp/pppoe.c:584
__sock_release net/socket.c:649 [inline]
sock_close+0xcd/0x230 net/socket.c:1336
__fput+0x3fe/0x8e0 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x6a3/0x2480 kernel/exit.c:874
do_group_exit+0x144/0x310 kernel/exit.c:996
get_signal+0xc66/0x14e0 kernel/signal.c:2897
arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
HARDIRQ-ON-R at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline]
_raw_read_lock_bh+0x39/0x50 kernel/locking/spinlock.c:252
ppp_channel_push+0x2c/0x220 drivers/net/ppp/ppp_generic.c:2185
ppp_write+0x291/0x390 drivers/net/ppp/ppp_generic.c:537
do_iter_write+0x39c/0x760 fs/read_write.c:857
vfs_writev fs/read_write.c:928 [inline]
do_pwritev+0x219/0x360 fs/read_write.c:1025
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
IN-SOFTIRQ-R at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline]
_raw_read_lock_bh+0x39/0x50 kernel/locking/spinlock.c:252
ppp_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306
ppp_async_process+0x7b/0x140 drivers/net/ppp/ppp_async.c:505
tasklet_action_common+0x3cb/0x4a0
handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
__do_softirq kernel/softirq.c:592 [inline]
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
sysvec_call_function_single+0x8e/0xb0 arch/x86/kernel/smp.c:243
asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:646
preempt_schedule_irq+0xf2/0x1c0 kernel/sched/core.c:6777
irqentry_exit+0x53/0x80 kernel/entry/common.c:432
asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643
__tasklet_schedule_common+0x1f9/0x260 kernel/softirq.c:737
tasklet_schedule include/linux/interrupt.h:657 [inline]
ppp_asynctty_receive+0x1ea2/0x2000 drivers/net/ppp/ppp_async.c:354
tty_ldisc_receive_buf+0x121/0x160 drivers/tty/tty_buffer.c:455
tty_port_default_receive_buf+0x6a/0x90 drivers/tty/tty_port.c:39
receive_buf drivers/tty/tty_buffer.c:471 [inline]
flush_to_ldisc+0x2b9/0x540 drivers/tty/tty_buffer.c:523
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
INITIAL USE at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline]
_raw_write_lock_bh+0x31/0x40 kernel/locking/spinlock.c:324
ppp_disconnect_channel+0x2f/0x2d0 drivers/net/ppp/ppp_generic.c:3521
ppp_unregister_channel+0xb5/0x2f0 drivers/net/ppp/ppp_generic.c:2995
pppox_unbind_sock+0x58/0xa0 drivers/net/ppp/pppox.c:58
pppoe_release+0x158/0x800 drivers/net/ppp/pppoe.c:584
__sock_release net/socket.c:649 [inline]
sock_close+0xcd/0x230 net/socket.c:1336
__fput+0x3fe/0x8e0 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x6a3/0x2480 kernel/exit.c:874
do_group_exit+0x144/0x310 kernel/exit.c:996
get_signal+0xc66/0x14e0 kernel/signal.c:2897
arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
INITIAL READ USE at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline]
_raw_read_lock_bh+0x39/0x50 kernel/locking/spinlock.c:252
ppp_channel_push+0x2c/0x220 drivers/net/ppp/ppp_generic.c:2185
ppp_write+0x291/0x390 drivers/net/ppp/ppp_generic.c:537
do_iter_write+0x39c/0x760 fs/read_write.c:857
vfs_writev fs/read_write.c:928 [inline]
do_pwritev+0x219/0x360 fs/read_write.c:1025
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
}
... key at: [<ffffffff96bb1580>] ppp_register_net_channel.__key.3+0x0/0x20
-> (&ppp->wlock){+...}-{2:2} {
HARDIRQ-ON-W at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_get_stats64+0xbf/0x290 drivers/net/ppp/ppp_generic.c:1538
dev_get_stats+0x90/0x370 net/core/dev.c:10704
rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205
rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782
rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856
rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline]
rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897
register_netdevice+0x13d2/0x1720 net/core/dev.c:10402
ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline]
ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272
ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline]
ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline]
ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
INITIAL USE at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_get_stats64+0xbf/0x290 drivers/net/ppp/ppp_generic.c:1538
dev_get_stats+0x90/0x370 net/core/dev.c:10704
rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205
rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782
rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856
rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline]
rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897
register_netdevice+0x13d2/0x1720 net/core/dev.c:10402
ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline]
ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272
ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline]
ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline]
ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
}
... key at: [<ffffffff96bb16e0>] ppp_dev_configure.__key.62+0x0/0x20
... acquired at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_connect_channel+0x170/0x640 drivers/net/ppp/ppp_generic.c:3483
ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> (&ppp->rlock){+...}-{2:2} {
HARDIRQ-ON-W at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_get_stats64+0x2f/0x290 drivers/net/ppp/ppp_generic.c:1533
dev_get_stats+0x90/0x370 net/core/dev.c:10704
rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205
rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782
rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856
rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline]
rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897
register_netdevice+0x13d2/0x1720 net/core/dev.c:10402
ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline]
ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272
ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline]
ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline]
ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
INITIAL USE at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_get_stats64+0x2f/0x290 drivers/net/ppp/ppp_generic.c:1533
dev_get_stats+0x90/0x370 net/core/dev.c:10704
rtnl_fill_stats+0x47/0x880 net/core/rtnetlink.c:1205
rtnl_fill_ifinfo+0x1598/0x1d60 net/core/rtnetlink.c:1782
rtmsg_ifinfo_build_skb+0xdc/0x180 net/core/rtnetlink.c:3856
rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline]
rtmsg_ifinfo+0x71/0x120 net/core/rtnetlink.c:3897
register_netdevice+0x13d2/0x1720 net/core/dev.c:10402
ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline]
ppp_dev_configure+0x853/0xad0 drivers/net/ppp/ppp_generic.c:1272
ppp_create_interface drivers/net/ppp/ppp_generic.c:3347 [inline]
ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1057 [inline]
ppp_ioctl+0x702/0x1cd0 drivers/net/ppp/ppp_generic.c:730
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
}
... key at: [<ffffffff96bb16c0>] ppp_dev_configure.__key+0x0/0x20
... acquired at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_dev_uninit+0x68/0x1a0 drivers/net/ppp/ppp_generic.c:1571
unregister_netdevice_many+0x12bb/0x18f0 net/core/dev.c:11111
unregister_netdevice_queue+0x2e6/0x350 net/core/dev.c:11027
unregister_netdevice include/linux/netdevice.h:3012 [inline]
ppp_release+0xec/0x1f0 drivers/net/ppp/ppp_generic.c:407
__fput+0x3fe/0x8e0 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
the dependencies between the lock to be acquired
and SOFTIRQ-READ-irq-unsafe lock:
-> (&pch->downl){+.+.}-{2:2} {
HARDIRQ-ON-W at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_unregister_channel+0x78/0x2f0 drivers/net/ppp/ppp_generic.c:2991
pppox_unbind_sock+0x58/0xa0 drivers/net/ppp/pppox.c:58
pppoe_release+0x158/0x800 drivers/net/ppp/pppoe.c:584
__sock_release net/socket.c:649 [inline]
sock_close+0xcd/0x230 net/socket.c:1336
__fput+0x3fe/0x8e0 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x6a3/0x2480 kernel/exit.c:874
do_group_exit+0x144/0x310 kernel/exit.c:996
get_signal+0xc66/0x14e0 kernel/signal.c:2897
arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
SOFTIRQ-ON-W at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:363 [inline]
ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2271 [inline]
ppp_input+0x160/0x980 drivers/net/ppp/ppp_generic.c:2303
pppoe_rcv_core+0x109/0x2f0 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv include/net/sock.h:1059 [inline]
__release_sock+0x198/0x4b0 net/core/sock.c:2724
release_sock+0x5d/0x1c0 net/core/sock.c:3265
pppoe_sendmsg+0xd1/0x740 drivers/net/ppp/pppoe.c:903
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
__sys_sendmmsg+0x2bf/0x560 net/socket.c:2571
__do_sys_sendmmsg net/socket.c:2600 [inline]
__se_sys_sendmmsg net/socket.c:2597 [inline]
__x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2597
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
INITIAL USE at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_unregister_channel+0x78/0x2f0 drivers/net/ppp/ppp_generic.c:2991
pppox_unbind_sock+0x58/0xa0 drivers/net/ppp/pppox.c:58
pppoe_release+0x158/0x800 drivers/net/ppp/pppoe.c:584
__sock_release net/socket.c:649 [inline]
sock_close+0xcd/0x230 net/socket.c:1336
__fput+0x3fe/0x8e0 fs/file_table.c:280
task_work_run+0x129/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x6a3/0x2480 kernel/exit.c:874
do_group_exit+0x144/0x310 kernel/exit.c:996
get_signal+0xc66/0x14e0 kernel/signal.c:2897
arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
}
... key at: [<ffffffff96bb1560>] ppp_register_net_channel.__key.1+0x0/0x20
... acquired at:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_connect_channel+0x190/0x640 drivers/net/ppp/ppp_generic.c:3484
ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
stack backtrace:
CPU: 1 PID: 7412 Comm: syz.3.652 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
print_bad_irq_dependency kernel/locking/lockdep.c:2567 [inline]
check_irq_usage kernel/locking/lockdep.c:2806 [inline]
check_prev_add kernel/locking/lockdep.c:3057 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain+0x4d01/0x5930 kernel/locking/lockdep.c:3788
__lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
ppp_connect_channel+0x190/0x640 drivers/net/ppp/ppp_generic.c:3484
ppp_ioctl+0xbe5/0x1cd0 drivers/net/ppp/ppp_generic.c:758
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1ebf2f1ff9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1ebd505038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1ebf4aa208 RCX: 00007f1ebf2f1ff9
RDX: 0000000020000300 RSI: 000000004004743a RDI: 0000000000000005
RBP: 00007f1ebf364296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f1ebf4aa208 R15: 00007ffe83837c88
</TASK>
Struck through repros no longer work on HEAD.