===================================================== WARNING: SOFTIRQ-READ-safe -> SOFTIRQ-READ-unsafe lock order detected 5.15.167-syzkaller #0 Not tainted ----------------------------------------------------- syz.2.255/5059 [HC0[0]:SC0[4]:HE1:SE0] is trying to acquire: ffff88801ab8add0 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] ffff88801ab8add0 (&ppp->rlock){+...}-{2:2}, at: ppp_ccp_closed+0x42/0x2a0 drivers/net/ppp/ppp_generic.c:3190 and this task is already holding: ffff88801ab8ae10 (&ppp->wlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] ffff88801ab8ae10 (&ppp->wlock){+...}-{2:2}, at: ppp_ccp_closed+0x31/0x2a0 drivers/net/ppp/ppp_generic.c:3190 which would create a new lock dependency: (&ppp->wlock){+...}-{2:2} -> (&ppp->rlock){+...}-{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 pppoe_rcv_core+0x109/0x2f0 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1059 [inline] __sk_receive_skb+0x416/0x9c0 net/core/sock.c:528 __netif_receive_skb_one_core net/core/dev.c:5485 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5599 process_backlog+0x363/0x7f0 net/core/dev.c:6476 __napi_poll+0xc7/0x440 net/core/dev.c:7035 napi_poll net/core/dev.c:7102 [inline] net_rx_action+0x617/0xda0 net/core/dev.c:7192 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_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 get_current arch/x86/include/asm/current.h:15 [inline] __syscall_enter_from_user_work kernel/entry/common.c:93 [inline] syscall_enter_from_user_mode+0x37/0x240 kernel/entry/common.c:114 do_syscall_64+0x1e/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x66/0xd0 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->wlock --> &pch->downl Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pch->downl); local_irq_disable(); lock(&pch->upl); lock(&ppp->wlock); lock(&pch->upl); *** DEADLOCK *** 1 lock held by syz.2.255/5059: #0: ffff88801ab8ae10 (&ppp->wlock){+...}-{2:2} , at: spin_lock_bh include/linux/spinlock.h:368 [inline] , at: ppp_ccp_closed+0x31/0x2a0 drivers/net/ppp/ppp_generic.c:3190 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 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 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_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306 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 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 pppoe_rcv_core+0x109/0x2f0 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1059 [inline] __sk_receive_skb+0x416/0x9c0 net/core/sock.c:528 __netif_receive_skb_one_core net/core/dev.c:5485 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5599 process_backlog+0x363/0x7f0 net/core/dev.c:6476 __napi_poll+0xc7/0x440 net/core/dev.c:7035 napi_poll net/core/dev.c:7102 [inline] net_rx_action+0x617/0xda0 net/core/dev.c:7192 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_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 get_current arch/x86/include/asm/current.h:15 [inline] __syscall_enter_from_user_work kernel/entry/common.c:93 [inline] syscall_enter_from_user_mode+0x37/0x240 kernel/entry/common.c:114 do_syscall_64+0x1e/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x66/0xd0 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 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 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_input+0x361/0x980 drivers/net/ppp/ppp_generic.c:2306 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 } ... key at: [] 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: [] 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 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 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 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 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 } ... key at: [] 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 -> (&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: [] 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_ccp_closed+0x42/0x2a0 drivers/net/ppp/ppp_generic.c:3190 ppp_destroy_interface+0x9f/0x300 drivers/net/ppp/ppp_generic.c:3394 ppp_release+0x17f/0x1f0 drivers/net/ppp/ppp_generic.c:413 __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 stack backtrace: CPU: 1 PID: 5059 Comm: syz.2.255 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __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_ccp_closed+0x42/0x2a0 drivers/net/ppp/ppp_generic.c:3190 ppp_destroy_interface+0x9f/0x300 drivers/net/ppp/ppp_generic.c:3394 ppp_release+0x17f/0x1f0 drivers/net/ppp/ppp_generic.c:413 __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 RIP: 0033:0x7f8441abaf39 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:00007ffe529ef878 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000023647 RCX: 00007f8441abaf39 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f8441c74a80 R08: 0000000000000001 R09: 00007ffe529efb6f R10: 00007f844193d000 R11: 0000000000000246 R12: 00000000000236ce R13: 00007ffe529ef980 R14: 0000000000000032 R15: ffffffffffffffff