===================================================== WARNING: SOFTIRQ-READ-safe -> SOFTIRQ-READ-unsafe lock order detected 6.11.0-syzkaller-02574-ga430d95c5efa #0 Not tainted ----------------------------------------------------- syz.3.3164/19154 [HC0[0]:SC0[8]:HE1:SE0] is trying to acquire: ffff88805f45e9e0 (&pch->downl){+.+.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88805f45e9e0 (&pch->downl){+.+.}-{2:2}, at: ppp_connect_channel drivers/net/ppp/ppp_generic.c:3485 [inline] ffff88805f45e9e0 (&pch->downl){+.+.}-{2:2}, at: ppp_ioctl+0x1955/0x2590 drivers/net/ppp/ppp_generic.c:761 and this task is already holding: ffff88802a76ae10 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88802a76ae10 (&ppp->rlock){+...}-{2:2}, at: ppp_connect_channel drivers/net/ppp/ppp_generic.c:3484 [inline] ffff88802a76ae10 (&ppp->rlock){+...}-{2:2}, at: ppp_ioctl+0x1942/0x2590 drivers/net/ppp/ppp_generic.c:761 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 kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3f/0x70 kernel/locking/spinlock.c:252 ppp_input_error+0x5f/0x210 drivers/net/ppp/ppp_generic.c:2344 ppp_sync_process+0x82/0x160 drivers/net/ppp/ppp_synctty.c:486 tasklet_action_common.constprop.0+0x24c/0x3e0 kernel/softirq.c:785 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 do_softirq kernel/softirq.c:455 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:442 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382 lock_sock include/net/sock.h:1609 [inline] tcp_sendmsg+0x20/0x50 net/ipv4/tcp.c:1356 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:853 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x4ac/0x5b0 net/socket.c:1166 new_sync_write fs/read_write.c:590 [inline] vfs_write+0x6b5/0x1140 fs/read_write.c:683 ksys_write+0x1f8/0x260 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f to a SOFTIRQ-READ-irq-unsafe lock: (&pch->downl){+.+.}-{2:2} ... which became SOFTIRQ-READ-irq-unsafe at: ... lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __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] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ppp_input+0x104/0xbb0 drivers/net/ppp/ppp_generic.c:2304 pppoe_rcv_core+0x22c/0x320 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1113 [inline] __release_sock+0x35f/0x400 net/core/sock.c:3072 release_sock+0x5a/0x220 net/core/sock.c:3626 pppoe_sendmsg+0x5e6/0x770 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2603 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2657 __sys_sendmmsg+0x1a1/0x450 net/socket.c:2743 __do_sys_sendmmsg net/socket.c:2772 [inline] __se_sys_sendmmsg net/socket.c:2769 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2769 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f 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); lock(&pch->upl); *** DEADLOCK *** 5 locks held by syz.3.3164/19154: #0: ffffffff8ef17588 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0xc3/0x2590 drivers/net/ppp/ppp_generic.c:729 #1: ffff888060ade8c0 (&pn->all_ppp_mutex){+.+.}-{3:3}, at: ppp_connect_channel drivers/net/ppp/ppp_generic.c:3474 [inline] #1: ffff888060ade8c0 (&pn->all_ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0xa5c/0x2590 drivers/net/ppp/ppp_generic.c:761 #2: ffff88805f45ea48 (&pch->upl){++.-}-{2:2}, at: ppp_connect_channel drivers/net/ppp/ppp_generic.c:3478 [inline] #2: ffff88805f45ea48 (&pch->upl){++.-}-{2:2}, at: ppp_ioctl+0xa8e/0x2590 drivers/net/ppp/ppp_generic.c:761 #3: ffff88802a76ae50 (&ppp->wlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #3: ffff88802a76ae50 (&ppp->wlock){+...}-{2:2}, at: ppp_connect_channel drivers/net/ppp/ppp_generic.c:3484 [inline] #3: ffff88802a76ae50 (&ppp->wlock){+...}-{2:2}, at: ppp_ioctl+0x192d/0x2590 drivers/net/ppp/ppp_generic.c:761 #4: ffff88802a76ae10 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #4: ffff88802a76ae10 (&ppp->rlock){+...}-{2:2}, at: ppp_connect_channel drivers/net/ppp/ppp_generic.c:3484 [inline] #4: ffff88802a76ae10 (&ppp->rlock){+...}-{2:2}, at: ppp_ioctl+0x1942/0x2590 drivers/net/ppp/ppp_generic.c:761 the dependencies between SOFTIRQ-READ-irq-safe lock and the holding lock: -> (&pch->upl){++.-}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x33/0x40 kernel/locking/spinlock.c:334 ppp_disconnect_channel+0x25/0x340 drivers/net/ppp/ppp_generic.c:3522 ppp_unregister_channel+0xb2/0x380 drivers/net/ppp/ppp_generic.c:2996 ppp_sync_close+0xe4/0x170 drivers/net/ppp/ppp_synctty.c:236 tty_ldisc_close+0x111/0x1a0 drivers/tty/tty_ldisc.c:455 tty_ldisc_kill+0x8e/0x150 drivers/tty/tty_ldisc.c:613 tty_ldisc_release+0x116/0x2a0 drivers/tty/tty_ldisc.c:781 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1696 tty_release+0xe25/0x1410 drivers/tty/tty_io.c:1867 __fput+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xaa3/0x2bb0 kernel/exit.c:882 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3f/0x70 kernel/locking/spinlock.c:252 ppp_input_error+0x5f/0x210 drivers/net/ppp/ppp_generic.c:2344 ppp_sync_process+0x82/0x160 drivers/net/ppp/ppp_synctty.c:486 tasklet_action_common.constprop.0+0x24c/0x3e0 kernel/softirq.c:785 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 do_softirq kernel/softirq.c:455 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:442 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382 lock_sock include/net/sock.h:1609 [inline] tcp_sendmsg+0x20/0x50 net/ipv4/tcp.c:1356 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:853 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x4ac/0x5b0 net/socket.c:1166 new_sync_write fs/read_write.c:590 [inline] vfs_write+0x6b5/0x1140 fs/read_write.c:683 ksys_write+0x1f8/0x260 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f IN-SOFTIRQ-R at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3f/0x70 kernel/locking/spinlock.c:252 ppp_input_error+0x5f/0x210 drivers/net/ppp/ppp_generic.c:2344 ppp_sync_process+0x82/0x160 drivers/net/ppp/ppp_synctty.c:486 tasklet_action_common.constprop.0+0x24c/0x3e0 kernel/softirq.c:785 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 do_softirq kernel/softirq.c:455 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:442 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382 lock_sock include/net/sock.h:1609 [inline] tcp_sendmsg+0x20/0x50 net/ipv4/tcp.c:1356 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:853 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x4ac/0x5b0 net/socket.c:1166 new_sync_write fs/read_write.c:590 [inline] vfs_write+0x6b5/0x1140 fs/read_write.c:683 ksys_write+0x1f8/0x260 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x33/0x40 kernel/locking/spinlock.c:334 ppp_disconnect_channel+0x25/0x340 drivers/net/ppp/ppp_generic.c:3522 ppp_unregister_channel+0xb2/0x380 drivers/net/ppp/ppp_generic.c:2996 ppp_sync_close+0xe4/0x170 drivers/net/ppp/ppp_synctty.c:236 tty_ldisc_close+0x111/0x1a0 drivers/tty/tty_ldisc.c:455 tty_ldisc_kill+0x8e/0x150 drivers/tty/tty_ldisc.c:613 tty_ldisc_release+0x116/0x2a0 drivers/tty/tty_ldisc.c:781 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1696 tty_release+0xe25/0x1410 drivers/tty/tty_io.c:1867 __fput+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xaa3/0x2bb0 kernel/exit.c:882 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3f/0x70 kernel/locking/spinlock.c:252 ppp_input_error+0x5f/0x210 drivers/net/ppp/ppp_generic.c:2344 ppp_sync_process+0x82/0x160 drivers/net/ppp/ppp_synctty.c:486 tasklet_action_common.constprop.0+0x24c/0x3e0 kernel/softirq.c:785 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 do_softirq kernel/softirq.c:455 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:442 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382 lock_sock include/net/sock.h:1609 [inline] tcp_sendmsg+0x20/0x50 net/ipv4/tcp.c:1356 inet_sendmsg+0xb9/0x140 net/ipv4/af_inet.c:853 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x4ac/0x5b0 net/socket.c:1166 new_sync_write fs/read_write.c:590 [inline] vfs_write+0x6b5/0x1140 fs/read_write.c:683 ksys_write+0x1f8/0x260 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.10+0x0/0x40 -> (&ppp->wlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0xcf/0x3a0 drivers/net/ppp/ppp_generic.c:1539 dev_get_stats+0xae/0x9e0 net/core/dev.c:10937 rtnl_fill_stats+0x48/0xa90 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo.constprop.0+0x1622/0x4b50 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x151/0x280 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4102 [inline] rtmsg_ifinfo+0x9f/0x1a0 net/core/rtnetlink.c:4121 register_netdevice+0x18b5/0x1e90 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x9aa/0xc90 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x17eb/0x2590 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18d/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0xcf/0x3a0 drivers/net/ppp/ppp_generic.c:1539 dev_get_stats+0xae/0x9e0 net/core/dev.c:10937 rtnl_fill_stats+0x48/0xa90 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo.constprop.0+0x1622/0x4b50 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x151/0x280 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4102 [inline] rtmsg_ifinfo+0x9f/0x1a0 net/core/rtnetlink.c:4121 register_netdevice+0x18b5/0x1e90 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x9aa/0xc90 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x17eb/0x2590 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18d/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.0+0x0/0x40 ... acquired at: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_connect_channel drivers/net/ppp/ppp_generic.c:3484 [inline] ppp_ioctl+0x192d/0x2590 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18d/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> (&ppp->rlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0x24/0x3a0 drivers/net/ppp/ppp_generic.c:1534 dev_get_stats+0xae/0x9e0 net/core/dev.c:10937 rtnl_fill_stats+0x48/0xa90 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo.constprop.0+0x1622/0x4b50 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x151/0x280 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4102 [inline] rtmsg_ifinfo+0x9f/0x1a0 net/core/rtnetlink.c:4121 register_netdevice+0x18b5/0x1e90 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x9aa/0xc90 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x17eb/0x2590 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18d/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_get_stats64+0x24/0x3a0 drivers/net/ppp/ppp_generic.c:1534 dev_get_stats+0xae/0x9e0 net/core/dev.c:10937 rtnl_fill_stats+0x48/0xa90 net/core/rtnetlink.c:1268 rtnl_fill_ifinfo.constprop.0+0x1622/0x4b50 net/core/rtnetlink.c:1909 rtmsg_ifinfo_build_skb+0x151/0x280 net/core/rtnetlink.c:4079 rtmsg_ifinfo_event net/core/rtnetlink.c:4112 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:4102 [inline] rtmsg_ifinfo+0x9f/0x1a0 net/core/rtnetlink.c:4121 register_netdevice+0x18b5/0x1e90 net/core/dev.c:10534 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline] ppp_dev_configure+0x9aa/0xc90 drivers/net/ppp/ppp_generic.c:1275 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x17eb/0x2590 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18d/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.1+0x0/0x40 ... acquired at: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_dev_uninit+0x67/0x1b0 drivers/net/ppp/ppp_generic.c:1572 unregister_netdevice_many_notify+0xf65/0x1e40 net/core/dev.c:11421 unregister_netdevice_many net/core/dev.c:11461 [inline] unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11335 unregister_netdevice include/linux/netdevice.h:3118 [inline] ppp_release+0x209/0x230 drivers/net/ppp/ppp_generic.c:410 __fput+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f the dependencies between the lock to be acquired and SOFTIRQ-READ-irq-unsafe lock: -> (&pch->downl){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_unregister_channel+0x6d/0x380 drivers/net/ppp/ppp_generic.c:2992 ppp_sync_close+0xe4/0x170 drivers/net/ppp/ppp_synctty.c:236 tty_ldisc_close+0x111/0x1a0 drivers/tty/tty_ldisc.c:455 tty_ldisc_kill+0x8e/0x150 drivers/tty/tty_ldisc.c:613 tty_ldisc_release+0x116/0x2a0 drivers/tty/tty_ldisc.c:781 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1696 tty_release+0xe25/0x1410 drivers/tty/tty_io.c:1867 __fput+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xaa3/0x2bb0 kernel/exit.c:882 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f SOFTIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __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] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2272 [inline] ppp_input+0x104/0xbb0 drivers/net/ppp/ppp_generic.c:2304 pppoe_rcv_core+0x22c/0x320 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1113 [inline] __release_sock+0x35f/0x400 net/core/sock.c:3072 release_sock+0x5a/0x220 net/core/sock.c:3626 pppoe_sendmsg+0x5e6/0x770 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2603 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2657 __sys_sendmmsg+0x1a1/0x450 net/socket.c:2743 __do_sys_sendmmsg net/socket.c:2772 [inline] __se_sys_sendmmsg net/socket.c:2769 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2769 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_unregister_channel+0x6d/0x380 drivers/net/ppp/ppp_generic.c:2992 ppp_sync_close+0xe4/0x170 drivers/net/ppp/ppp_synctty.c:236 tty_ldisc_close+0x111/0x1a0 drivers/tty/tty_ldisc.c:455 tty_ldisc_kill+0x8e/0x150 drivers/tty/tty_ldisc.c:613 tty_ldisc_release+0x116/0x2a0 drivers/tty/tty_ldisc.c:781 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1696 tty_release+0xe25/0x1410 drivers/tty/tty_io.c:1867 __fput+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xaa3/0x2bb0 kernel/exit.c:882 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f } ... key at: [] __key.11+0x0/0x40 ... acquired at: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_connect_channel drivers/net/ppp/ppp_generic.c:3485 [inline] ppp_ioctl+0x1955/0x2590 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18d/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f stack backtrace: CPU: 1 UID: 0 PID: 19154 Comm: syz.3.3164 Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 print_bad_irq_dependency kernel/locking/lockdep.c:2625 [inline] check_irq_usage+0xe3c/0x1490 kernel/locking/lockdep.c:2864 check_prev_add kernel/locking/lockdep.c:3137 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2503/0x3cb0 kernel/locking/lockdep.c:5142 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] ppp_connect_channel drivers/net/ppp/ppp_generic.c:3485 [inline] ppp_ioctl+0x1955/0x2590 drivers/net/ppp/ppp_generic.c:761 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18d/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5d7af7def9 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:00007f5d7bd6d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5d7b135f80 RCX: 00007f5d7af7def9 RDX: 0000000020000300 RSI: 000000004004743a RDI: 0000000000000005 RBP: 00007f5d7aff0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5d7b135f80 R15: 00007ffd77b98d28