===================================================== WARNING: SOFTIRQ-READ-safe -> SOFTIRQ-READ-unsafe lock order detected 5.15.167-syzkaller #0 Not tainted ----------------------------------------------------- syz.1.432/5739 [HC0[0]:SC0[8]:HE1:SE0] is trying to acquire: ffff0000cdcd11e0 (&pch->downl){+.+.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] ffff0000cdcd11e0 (&pch->downl){+.+.}-{2:2}, at: ppp_connect_channel+0x160/0x580 drivers/net/ppp/ppp_generic.c:3484 and this task is already holding: ffff0000d6bf2dd0 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] ffff0000d6bf2dd0 (&ppp->rlock){+...}-{2:2}, at: ppp_connect_channel+0x154/0x580 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+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x154/0x224 kernel/locking/spinlock.c:252 ppp_input+0x344/0x840 drivers/net/ppp/ppp_generic.c:2306 ppp_sync_process+0x88/0x160 drivers/net/ppp/ppp_synctty.c:501 tasklet_action_common+0x364/0x404 tasklet_action+0x60/0x84 kernel/softirq.c:809 handle_softirqs+0x384/0xdbc kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] do_softirq+0xfc/0x1b0 kernel/softirq.c:459 __local_bh_enable_ip+0x298/0x470 kernel/softirq.c:383 local_bh_enable+0x20/0x2c include/linux/bottom_half.h:32 srcu_invoke_callbacks+0x188/0x370 kernel/rcu/srcutree.c:1273 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 to a SOFTIRQ-READ-irq-unsafe lock: (&pch->downl){+.+.}-{2:2} ... which became SOFTIRQ-READ-irq-unsafe at: ... lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0xb0/0x10c 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+0x168/0x840 drivers/net/ppp/ppp_generic.c:2303 pppoe_rcv_core+0xf8/0x330 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1059 [inline] __release_sock+0x1a8/0x408 net/core/sock.c:2724 release_sock+0x68/0x270 net/core/sock.c:3265 pppoe_sendmsg+0xc8/0x5d0 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x584/0x870 net/socket.c:2431 ___sys_sendmsg+0x214/0x294 net/socket.c:2485 __sys_sendmmsg+0x23c/0x648 net/socket.c:2571 __do_sys_sendmmsg net/socket.c:2600 [inline] __se_sys_sendmmsg net/socket.c:2597 [inline] __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2597 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 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.1.432/5739: #0: ffff80001610f868 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x118/0x2870 drivers/net/ppp/ppp_generic.c:726 #1: ffff0000ca64d0c0 (&pn->all_ppp_mutex){+.+.}-{3:3}, at: ppp_connect_channel+0x74/0x580 drivers/net/ppp/ppp_generic.c:3473 #2: ffff0000cdcd1240 (&pch->upl){++.-}-{2:2}, at: ppp_connect_channel+0x94/0x580 drivers/net/ppp/ppp_generic.c:3477 #3: ffff0000d6bf2e10 (&ppp->wlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] #3: ffff0000d6bf2e10 (&ppp->wlock){+...}-{2:2}, at: ppp_connect_channel+0x148/0x580 drivers/net/ppp/ppp_generic.c:3483 #4: ffff0000d6bf2dd0 (&ppp->rlock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] #4: ffff0000d6bf2dd0 (&ppp->rlock){+...}-{2:2}, at: ppp_connect_channel+0x154/0x580 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+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline] _raw_write_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:324 ppp_disconnect_channel+0x3c/0x2ac drivers/net/ppp/ppp_generic.c:3521 ppp_unregister_channel+0xa8/0x2c0 drivers/net/ppp/ppp_generic.c:2995 pppox_unbind_sock+0x68/0xbc drivers/net/ppp/pppox.c:58 pppoe_connect+0x200/0xd68 drivers/net/ppp/pppoe.c:646 __sys_connect_file net/socket.c:1918 [inline] __sys_connect+0x268/0x290 net/socket.c:1935 __do_sys_connect net/socket.c:1945 [inline] __se_sys_connect net/socket.c:1942 [inline] __arm64_sys_connect+0x7c/0x94 net/socket.c:1942 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 HARDIRQ-ON-R at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x154/0x224 kernel/locking/spinlock.c:252 ppp_channel_push+0x38/0x208 drivers/net/ppp/ppp_generic.c:2185 ppp_write+0x314/0x454 drivers/net/ppp/ppp_generic.c:537 vfs_write+0x280/0xb44 fs/read_write.c:592 ksys_write+0x15c/0x26c fs/read_write.c:647 __do_sys_write fs/read_write.c:659 [inline] __se_sys_write fs/read_write.c:656 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:656 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 IN-SOFTIRQ-R at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x154/0x224 kernel/locking/spinlock.c:252 ppp_input+0x344/0x840 drivers/net/ppp/ppp_generic.c:2306 ppp_sync_process+0x88/0x160 drivers/net/ppp/ppp_synctty.c:501 tasklet_action_common+0x364/0x404 tasklet_action+0x60/0x84 kernel/softirq.c:809 handle_softirqs+0x384/0xdbc kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] do_softirq+0xfc/0x1b0 kernel/softirq.c:459 __local_bh_enable_ip+0x298/0x470 kernel/softirq.c:383 local_bh_enable+0x20/0x2c include/linux/bottom_half.h:32 srcu_invoke_callbacks+0x188/0x370 kernel/rcu/srcutree.c:1273 process_one_work+0x790/0x11b8 kernel/workqueue.c:2310 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 INITIAL USE at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline] _raw_write_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:324 ppp_disconnect_channel+0x3c/0x2ac drivers/net/ppp/ppp_generic.c:3521 ppp_unregister_channel+0xa8/0x2c0 drivers/net/ppp/ppp_generic.c:2995 pppox_unbind_sock+0x68/0xbc drivers/net/ppp/pppox.c:58 pppoe_connect+0x200/0xd68 drivers/net/ppp/pppoe.c:646 __sys_connect_file net/socket.c:1918 [inline] __sys_connect+0x268/0x290 net/socket.c:1935 __do_sys_connect net/socket.c:1945 [inline] __se_sys_connect net/socket.c:1942 [inline] __arm64_sys_connect+0x7c/0x94 net/socket.c:1942 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 INITIAL READ USE at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x154/0x224 kernel/locking/spinlock.c:252 ppp_channel_push+0x38/0x208 drivers/net/ppp/ppp_generic.c:2185 ppp_write+0x314/0x454 drivers/net/ppp/ppp_generic.c:537 vfs_write+0x280/0xb44 fs/read_write.c:592 ksys_write+0x15c/0x26c fs/read_write.c:647 __do_sys_write fs/read_write.c:659 [inline] __se_sys_write fs/read_write.c:656 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:656 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 } ... key at: [] ppp_register_net_channel.__key.3+0x0/0x20 -> (&ppp->wlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0xbc/0x268 drivers/net/ppp/ppp_generic.c:1538 dev_get_stats+0x9c/0x1e0 net/core/dev.c:10704 rtnl_fill_stats+0x50/0x7c0 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x125c/0x1970 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xf8/0x1b4 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x8c/0x128 net/core/rtnetlink.c:3897 register_netdevice+0xff8/0x12d4 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x720/0x9e0 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+0xa88/0x2870 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 fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 INITIAL USE at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0xbc/0x268 drivers/net/ppp/ppp_generic.c:1538 dev_get_stats+0x9c/0x1e0 net/core/dev.c:10704 rtnl_fill_stats+0x50/0x7c0 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x125c/0x1970 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xf8/0x1b4 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x8c/0x128 net/core/rtnetlink.c:3897 register_netdevice+0xff8/0x12d4 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x720/0x9e0 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+0xa88/0x2870 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 fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 } ... key at: [] ppp_dev_configure.__key.67+0x0/0x20 ... acquired at: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x148/0x580 drivers/net/ppp/ppp_generic.c:3483 ppp_ioctl+0x1450/0x2870 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 fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> (&ppp->rlock){+...}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0x3c/0x268 drivers/net/ppp/ppp_generic.c:1533 dev_get_stats+0x9c/0x1e0 net/core/dev.c:10704 rtnl_fill_stats+0x50/0x7c0 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x125c/0x1970 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xf8/0x1b4 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x8c/0x128 net/core/rtnetlink.c:3897 register_netdevice+0xff8/0x12d4 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x720/0x9e0 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+0xa88/0x2870 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 fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 INITIAL USE at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_get_stats64+0x3c/0x268 drivers/net/ppp/ppp_generic.c:1533 dev_get_stats+0x9c/0x1e0 net/core/dev.c:10704 rtnl_fill_stats+0x50/0x7c0 net/core/rtnetlink.c:1205 rtnl_fill_ifinfo+0x125c/0x1970 net/core/rtnetlink.c:1782 rtmsg_ifinfo_build_skb+0xf8/0x1b4 net/core/rtnetlink.c:3856 rtmsg_ifinfo_event net/core/rtnetlink.c:3888 [inline] rtmsg_ifinfo+0x8c/0x128 net/core/rtnetlink.c:3897 register_netdevice+0xff8/0x12d4 net/core/dev.c:10402 ppp_unit_register drivers/net/ppp/ppp_generic.c:1216 [inline] ppp_dev_configure+0x720/0x9e0 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+0xa88/0x2870 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 fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 } ... key at: [] ppp_dev_configure.__key+0x0/0x20 ... acquired at: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_dev_uninit+0x68/0x168 drivers/net/ppp/ppp_generic.c:1571 unregister_netdevice_many+0x11cc/0x189c net/core/dev.c:11111 unregister_netdevice_queue+0x2d0/0x31c net/core/dev.c:11027 unregister_netdevice include/linux/netdevice.h:3012 [inline] ppp_release+0xe8/0x230 drivers/net/ppp/ppp_generic.c:407 __fput+0x1c4/0x800 fs/file_table.c:280 ____fput+0x20/0x30 fs/file_table.c:308 task_work_run+0x130/0x1e4 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 the dependencies between the lock to be acquired and SOFTIRQ-READ-irq-unsafe lock: -> (&pch->downl){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_unregister_channel+0x78/0x2c0 drivers/net/ppp/ppp_generic.c:2991 pppox_unbind_sock+0x68/0xbc drivers/net/ppp/pppox.c:58 pppoe_connect+0x200/0xd68 drivers/net/ppp/pppoe.c:646 __sys_connect_file net/socket.c:1918 [inline] __sys_connect+0x268/0x290 net/socket.c:1935 __do_sys_connect net/socket.c:1945 [inline] __se_sys_connect net/socket.c:1942 [inline] __arm64_sys_connect+0x7c/0x94 net/socket.c:1942 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 SOFTIRQ-ON-W at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0xb0/0x10c 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+0x168/0x840 drivers/net/ppp/ppp_generic.c:2303 pppoe_rcv_core+0xf8/0x330 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1059 [inline] __release_sock+0x1a8/0x408 net/core/sock.c:2724 release_sock+0x68/0x270 net/core/sock.c:3265 pppoe_sendmsg+0xc8/0x5d0 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x584/0x870 net/socket.c:2431 ___sys_sendmsg+0x214/0x294 net/socket.c:2485 __sys_sendmmsg+0x23c/0x648 net/socket.c:2571 __do_sys_sendmmsg net/socket.c:2600 [inline] __se_sys_sendmmsg net/socket.c:2597 [inline] __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2597 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 INITIAL USE at: lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_unregister_channel+0x78/0x2c0 drivers/net/ppp/ppp_generic.c:2991 pppox_unbind_sock+0x68/0xbc drivers/net/ppp/pppox.c:58 pppoe_connect+0x200/0xd68 drivers/net/ppp/pppoe.c:646 __sys_connect_file net/socket.c:1918 [inline] __sys_connect+0x268/0x290 net/socket.c:1935 __do_sys_connect net/socket.c:1945 [inline] __se_sys_connect net/socket.c:1942 [inline] __arm64_sys_connect+0x7c/0x94 net/socket.c:1942 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 } ... key at: [] ppp_register_net_channel.__key.1+0x0/0x20 ... acquired at: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x160/0x580 drivers/net/ppp/ppp_generic.c:3484 ppp_ioctl+0x1450/0x2870 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 fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 stack backtrace: CPU: 0 PID: 5739 Comm: syz.1.432 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 __lock_acquire+0x62bc/0x7638 kernel/locking/lockdep.c:5012 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ppp_connect_channel+0x160/0x580 drivers/net/ppp/ppp_generic.c:3484 ppp_ioctl+0x1450/0x2870 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 fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584