usb 5-1: async_complete: urb error -71 usb 5-1: async_complete: urb error -71 usb 5-1: async_complete: urb error -71 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.3.90/6265 is trying to acquire lock: ffff888064996ba0 (slock-AF_PHONET){+...}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] ffff888064996ba0 (slock-AF_PHONET){+...}-{3:3}, at: __sk_receive_skb+0x1f1/0x9e0 net/core/sock.c:565 but task is already holding lock: ffff88803960f460 (slock-AF_PHONET/1){+.+.}-{3:3}, at: __sk_receive_skb+0x1bf/0x9e0 net/core/sock.c:563 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (slock-AF_PHONET/1){+.+.}-{3:3}: rt_spin_lock_nested+0x81/0x3f0 kernel/locking/spinlock_rt.c:64 __sk_receive_skb+0x1bf/0x9e0 net/core/sock.c:563 sk_receive_skb include/net/sock.h:2022 [inline] pep_do_rcv+0x685/0xaa0 net/phonet/pep.c:675 sk_backlog_rcv include/net/sock.h:1190 [inline] __sk_receive_skb+0x962/0x9e0 net/core/sock.c:572 sk_receive_skb include/net/sock.h:2022 [inline] phonet_rcv+0x781/0xc40 net/phonet/af_phonet.c:-1 __netif_receive_skb_one_core net/core/dev.c:6209 [inline] __netif_receive_skb net/core/dev.c:6322 [inline] process_backlog+0x5e1/0xc60 net/core/dev.c:6673 __napi_poll+0xab/0x550 net/core/dev.c:7737 napi_poll net/core/dev.c:7800 [inline] net_rx_action+0x696/0xe00 net/core/dev.c:7957 handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] __local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:912 [inline] __dev_queue_xmit+0x1eaf/0x3900 net/core/dev.c:4905 dev_queue_xmit include/linux/netdevice.h:3401 [inline] batadv_send_skb_packet+0x418/0x690 net/batman-adv/send.c:100 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:391 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:419 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x631/0x7e0 net/batman-adv/bat_iv_ogm.c:1700 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 (slock-AF_PHONET){+...}-{3:3}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56 spin_lock include/linux/spinlock_rt.h:45 [inline] __sk_receive_skb+0x1f1/0x9e0 net/core/sock.c:565 sk_receive_skb include/net/sock.h:2022 [inline] phonet_rcv+0x781/0xc40 net/phonet/af_phonet.c:-1 __netif_receive_skb_one_core net/core/dev.c:6209 [inline] __netif_receive_skb net/core/dev.c:6322 [inline] process_backlog+0x5e1/0xc60 net/core/dev.c:6673 __napi_poll+0xab/0x550 net/core/dev.c:7737 napi_poll net/core/dev.c:7800 [inline] net_rx_action+0x696/0xe00 net/core/dev.c:7957 handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] __local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302 local_bh_enable include/linux/bottom_half.h:33 [inline] netif_rx+0xb9/0xf0 net/core/dev.c:5775 pn_send+0x62a/0x8e0 net/phonet/af_phonet.c:188 pn_skb_send+0x218/0x510 net/phonet/af_phonet.c:275 pep_indicate net/phonet/pep.c:123 [inline] pipe_snd_status+0x1f1/0x320 net/phonet/pep.c:221 pipe_grant_credits net/phonet/pep.c:244 [inline] pipe_do_rcv+0xf15/0x16a0 net/phonet/pep.c:433 sk_backlog_rcv include/net/sock.h:1190 [inline] __sk_receive_skb+0x962/0x9e0 net/core/sock.c:572 sk_receive_skb include/net/sock.h:2022 [inline] pep_do_rcv+0x685/0xaa0 net/phonet/pep.c:675 sk_backlog_rcv include/net/sock.h:1190 [inline] __release_sock+0x2a9/0x3d0 net/core/sock.c:3216 release_sock+0x1be/0x290 net/core/sock.c:3815 pep_sock_accept+0xd47/0x11e0 net/phonet/pep.c:879 pn_socket_accept+0xc1/0x310 net/phonet/socket.c:303 do_accept+0x52b/0x760 net/socket.c:2047 __sys_accept4_file net/socket.c:2081 [inline] __sys_accept4+0x139/0x230 net/socket.c:2103 __do_sys_accept4 net/socket.c:2110 [inline] __se_sys_accept4 net/socket.c:2107 [inline] __x64_sys_accept4+0x9a/0xb0 net/socket.c:2107 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(slock-AF_PHONET/1); lock(slock-AF_PHONET); lock(slock-AF_PHONET/1); lock(slock-AF_PHONET); *** DEADLOCK *** 6 locks held by syz.3.90/6265: #0: ffff888064997518 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline] #0: ffff888064997518 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: pep_sock_accept+0x107/0x11e0 net/phonet/pep.c:780 #1: ffff88803960f460 (slock-AF_PHONET/1){+.+.}-{3:3}, at: __sk_receive_skb+0x1bf/0x9e0 net/core/sock.c:563 #2: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #2: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #2: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #2: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock_nested+0x1de/0x3f0 kernel/locking/spinlock_rt.c:65 #3: ffff88803960f518 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: sk_receive_skb include/net/sock.h:2022 [inline] #3: ffff88803960f518 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: pep_do_rcv+0x685/0xaa0 net/phonet/pep.c:675 #4: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163 #5: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #5: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #5: ffffffff8dfc80c0 (rcu_read_lock){....}-{1:3}, at: process_backlog+0x271/0xc60 net/core/dev.c:6672 stack backtrace: CPU: 1 UID: 0 PID: 6265 Comm: syz.3.90 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56 spin_lock include/linux/spinlock_rt.h:45 [inline] __sk_receive_skb+0x1f1/0x9e0 net/core/sock.c:565 sk_receive_skb include/net/sock.h:2022 [inline] phonet_rcv+0x781/0xc40 net/phonet/af_phonet.c:-1 __netif_receive_skb_one_core net/core/dev.c:6209 [inline] __netif_receive_skb net/core/dev.c:6322 [inline] process_backlog+0x5e1/0xc60 net/core/dev.c:6673 __napi_poll+0xab/0x550 net/core/dev.c:7737 napi_poll net/core/dev.c:7800 [inline] net_rx_action+0x696/0xe00 net/core/dev.c:7957 handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] __local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302 local_bh_enable include/linux/bottom_half.h:33 [inline] netif_rx+0xb9/0xf0 net/core/dev.c:5775 pn_send+0x62a/0x8e0 net/phonet/af_phonet.c:188 pn_skb_send+0x218/0x510 net/phonet/af_phonet.c:275 pep_indicate net/phonet/pep.c:123 [inline] pipe_snd_status+0x1f1/0x320 net/phonet/pep.c:221 pipe_grant_credits net/phonet/pep.c:244 [inline] pipe_do_rcv+0xf15/0x16a0 net/phonet/pep.c:433 sk_backlog_rcv include/net/sock.h:1190 [inline] __sk_receive_skb+0x962/0x9e0 net/core/sock.c:572 sk_receive_skb include/net/sock.h:2022 [inline] pep_do_rcv+0x685/0xaa0 net/phonet/pep.c:675 sk_backlog_rcv include/net/sock.h:1190 [inline] __release_sock+0x2a9/0x3d0 net/core/sock.c:3216 release_sock+0x1be/0x290 net/core/sock.c:3815 pep_sock_accept+0xd47/0x11e0 net/phonet/pep.c:879 pn_socket_accept+0xc1/0x310 net/phonet/socket.c:303 do_accept+0x52b/0x760 net/socket.c:2047 __sys_accept4_file net/socket.c:2081 [inline] __sys_accept4+0x139/0x230 net/socket.c:2103 __do_sys_accept4 net/socket.c:2110 [inline] __se_sys_accept4 net/socket.c:2107 [inline] __x64_sys_accept4+0x9a/0xb0 net/socket.c:2107 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f159266c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f15908a5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000120 RAX: ffffffffffffffda RBX: 00007f15928e6090 RCX: 00007f159266c819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f1592702c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000080000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f15928e6128 R14: 00007f15928e6090 R15: 00007ffe0e5ac308