vxcan0: j1939_tp_rxtimer: 0xffff888077469c00: rx timeout, send abort ====================================================== WARNING: possible circular locking dependency detected 6.2.0-rc5-syzkaller-00108-g83abd4d4c4be #0 Not tainted ------------------------------------------------------ syz-executor.1/23401 is trying to acquire lock: ffff88803945d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88803945d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 but task is already holding lock: ffff88803945d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88803945d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88803945d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe9/0x220 net/can/j1939/transport.c:1248 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&priv->active_session_list_lock){+.-.}-{2:2}: __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:355 [inline] j1939_session_list_lock net/can/j1939/transport.c:238 [inline] j1939_session_activate+0x47/0x4b0 net/can/j1939/transport.c:1561 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x1b6/0x450 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1109 [inline] j1939_session_completed+0x19a/0x1f0 net/can/j1939/transport.c:1222 j1939_xtp_rx_eoma_one net/can/j1939/transport.c:1392 [inline] j1939_xtp_rx_eoma+0x2a1/0x5e0 net/can/j1939/transport.c:1407 j1939_tp_cmd_recv net/can/j1939/transport.c:2096 [inline] j1939_tp_recv+0x71c/0xcd0 net/can/j1939/transport.c:2141 j1939_can_recv net/can/j1939/main.c:112 [inline] j1939_can_recv+0x78e/0xa30 net/can/j1939/main.c:38 deliver net/can/af_can.c:572 [inline] can_rcv_filter+0x5d4/0x8d0 net/can/af_can.c:606 can_receive+0x31d/0x580 net/can/af_can.c:663 can_rcv+0x1e1/0x230 net/can/af_can.c:687 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5482 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5596 process_backlog+0x3e4/0x810 net/core/dev.c:5924 __napi_poll+0xb8/0x770 net/core/dev.c:6485 napi_poll net/core/dev.c:6552 [inline] net_rx_action+0xa00/0xde0 net/core/dev.c:6663 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0xa20 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #1 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: __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:355 [inline] j1939_sk_queue_drop_all+0x3b/0x2f0 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0x7f/0x160 net/can/j1939/socket.c:1275 j1939_netdev_notify+0x19d/0x1d0 net/can/j1939/main.c:379 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1944 call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] call_netdevice_notifiers net/core/dev.c:1996 [inline] __dev_notify_flags+0x1ea/0x2d0 net/core/dev.c:8571 dev_change_flags+0x11b/0x170 net/core/dev.c:8607 do_setlink+0x9f1/0x3bb0 net/core/rtnetlink.c:2827 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3590 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&priv->j1939_socks_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __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:355 [inline] j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 __j1939_session_cancel+0x3b9/0x460 net/can/j1939/transport.c:1132 j1939_tp_rxtimer.cold+0x1f6/0x24f net/can/j1939/transport.c:1257 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 lock_acquire+0x59/0x630 kernel/locking/lockdep.c:5636 __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:350 [inline] drop_pagecache_sb+0x147/0x2a0 fs/drop_caches.c:24 iterate_supers+0x140/0x2a0 fs/super.c:724 drop_caches_sysctl_handler+0xdf/0x110 fs/drop_caches.c:62 proc_sys_call_handler+0x49c/0x6d0 fs/proc/proc_sysctl.c:604 call_write_iter include/linux/fs.h:2189 [inline] do_iter_readv_writev+0x20b/0x3b0 fs/read_write.c:735 do_iter_write+0x182/0x700 fs/read_write.c:861 vfs_iter_write+0x74/0xa0 fs/read_write.c:902 iter_file_splice_write+0x745/0xc90 fs/splice.c:686 do_splice_from fs/splice.c:764 [inline] direct_splice_actor+0x114/0x180 fs/splice.c:931 splice_direct_to_actor+0x335/0x8a0 fs/splice.c:886 do_splice_direct+0x1ab/0x280 fs/splice.c:974 do_sendfile+0xb19/0x1270 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1309 [inline] __x64_sys_sendfile64+0x14d/0x210 fs/read_write.c:1309 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &priv->j1939_socks_lock --> &jsk->sk_session_queue_lock --> &priv->active_session_list_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&priv->active_session_list_lock); lock(&jsk->sk_session_queue_lock); lock(&priv->active_session_list_lock); lock(&priv->j1939_socks_lock); *** DEADLOCK *** 4 locks held by syz-executor.1/23401: #0: ffff888021e3e460 (sb_writers#3){.+.+}-{0:0}, at: __do_sys_sendfile64 fs/read_write.c:1317 [inline] #0: ffff888021e3e460 (sb_writers#3){.+.+}-{0:0}, at: __se_sys_sendfile64 fs/read_write.c:1309 [inline] #0: ffff888021e3e460 (sb_writers#3){.+.+}-{0:0}, at: __x64_sys_sendfile64+0x14d/0x210 fs/read_write.c:1309 #1: ffff88802b5b80e0 (&type->s_umount_key#51){++++}-{3:3}, at: iterate_supers+0xdf/0x2a0 fs/super.c:722 #2: ffff88802b5b89d8 (&s->s_inode_list_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline] #2: ffff88802b5b89d8 (&s->s_inode_list_lock){+.+.}-{2:2}, at: drop_pagecache_sb+0x29/0x2a0 fs/drop_caches.c:22 #3: ffff88803945d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #3: ffff88803945d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #3: ffff88803945d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe9/0x220 net/can/j1939/transport.c:1248 stack backtrace: CPU: 0 PID: 23401 Comm: syz-executor.1 Not tainted 6.2.0-rc5-syzkaller-00108-g83abd4d4c4be #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __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:355 [inline] j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 __j1939_session_cancel+0x3b9/0x460 net/can/j1939/transport.c:1132 j1939_tp_rxtimer.cold+0x1f6/0x24f net/can/j1939/transport.c:1257 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_acquire+0x59/0x630 kernel/locking/lockdep.c:5636 Code: 8d 5c 24 18 4c 89 0c 24 48 c7 44 24 18 b3 8a b5 41 48 c1 eb 03 48 c7 44 24 20 af a4 f0 8b 48 01 d8 48 c7 44 24 28 80 26 63 81 00 f1 f1 f1 f1 c7 40 04 f1 f1 00 00 c7 40 08 00 00 00 f3 c7 40 RSP: 0018:ffffc900047ef550 EFLAGS: 00000282 RAX: fffff520008fdead RBX: 1ffff920008fdead RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88807a6b25f0 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: ffffed100f4d6419 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88807a6b25f0 R15: 0000000000000000 __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:350 [inline] drop_pagecache_sb+0x147/0x2a0 fs/drop_caches.c:24 iterate_supers+0x140/0x2a0 fs/super.c:724 drop_caches_sysctl_handler+0xdf/0x110 fs/drop_caches.c:62 proc_sys_call_handler+0x49c/0x6d0 fs/proc/proc_sysctl.c:604 call_write_iter include/linux/fs.h:2189 [inline] do_iter_readv_writev+0x20b/0x3b0 fs/read_write.c:735 do_iter_write+0x182/0x700 fs/read_write.c:861 vfs_iter_write+0x74/0xa0 fs/read_write.c:902 iter_file_splice_write+0x745/0xc90 fs/splice.c:686 do_splice_from fs/splice.c:764 [inline] direct_splice_actor+0x114/0x180 fs/splice.c:931 splice_direct_to_actor+0x335/0x8a0 fs/splice.c:886 do_splice_direct+0x1ab/0x280 fs/splice.c:974 do_sendfile+0xb19/0x1270 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1309 [inline] __x64_sys_sendfile64+0x14d/0x210 fs/read_write.c:1309 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6b0108c0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6aff9bc168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f6b011ac1f0 RCX: 00007f6b0108c0c9 RDX: 0000000020002080 RSI: 0000000000000007 RDI: 0000000000000008 RBP: 00007f6b010e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000870 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd2fdc98df R14: 00007f6aff9bc300 R15: 0000000000022000 vxcan0: j1939_tp_rxtimer: 0xffff888077469c00: abort rx timeout. Force session deactivation ---------------- Code disassembly (best guess): 0: 8d 5c 24 18 lea 0x18(%rsp),%ebx 4: 4c 89 0c 24 mov %r9,(%rsp) 8: 48 c7 44 24 18 b3 8a movq $0x41b58ab3,0x18(%rsp) f: b5 41 11: 48 c1 eb 03 shr $0x3,%rbx 15: 48 c7 44 24 20 af a4 movq $0xffffffff8bf0a4af,0x20(%rsp) 1c: f0 8b 1e: 48 01 d8 add %rbx,%rax 21: 48 c7 44 24 28 80 26 movq $0xffffffff81632680,0x28(%rsp) 28: 63 81 * 2a: c7 00 f1 f1 f1 f1 movl $0xf1f1f1f1,(%rax) <-- trapping instruction 30: c7 40 04 f1 f1 00 00 movl $0xf1f1,0x4(%rax) 37: c7 40 08 00 00 00 f3 movl $0xf3000000,0x8(%rax) 3e: c7 .byte 0xc7 3f: 40 rex