netlink: 'syz-executor.3': attribute type 21 has an invalid length.
netlink: 'syz-executor.3': attribute type 1 has an invalid length.
FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 1
======================================================
WARNING: possible circular locking dependency detected
6.7.0-rc5-syzkaller-01540-g5abde6246522 #0 Not tainted
------------------------------------------------------
syz-executor.3/5651 is trying to acquire lock:
ffffffff8cf99798 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139

but task is already holding lock:
ffff8880b993c718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&rq->__lock){-.-.}-{2:2}:
       _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
       raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558
       raw_spin_rq_lock kernel/sched/sched.h:1349 [inline]
       rq_lock kernel/sched/sched.h:1663 [inline]
       task_fork_fair+0x70/0x240 kernel/sched/fair.c:12586
       sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4812
       copy_process+0x4c86/0x73f0 kernel/fork.c:2609
       kernel_clone+0xfd/0x930 kernel/fork.c:2907
       user_mode_thread+0xb4/0xf0 kernel/fork.c:2985
       rest_init+0x27/0x2b0 init/main.c:695
       arch_call_rest_init+0x13/0x30 init/main.c:827
       start_kernel+0x39f/0x480 init/main.c:1072
       x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:555
       x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:536
       secondary_startup_64_no_verify+0x166/0x16b

-> #1 (&p->pi_lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:518 [inline]
       try_to_wake_up+0xb0/0x13d0 kernel/sched/core.c:4226
       up+0x79/0xb0 kernel/locking/semaphore.c:191
       __up_console_sem kernel/printk/printk.c:340 [inline]
       __console_unlock kernel/printk/printk.c:2706 [inline]
       console_unlock+0x1cf/0x260 kernel/printk/printk.c:3038
       vprintk_emit+0x17f/0x5f0 kernel/printk/printk.c:2303
       vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
       _printk+0xc8/0x100 kernel/printk/printk.c:2328
       test_rcu_tasks_callback+0x33/0x70 kernel/rcu/tasks.h:2004
       rcu_tasks_invoke_cbs+0x2b4/0x7d0 kernel/rcu/tasks.h:545
       rcu_tasks_one_gp+0x880/0xf20 kernel/rcu/tasks.h:595
       rcu_tasks_kthread+0x1c8/0x260 kernel/rcu/tasks.h:625
       kthread+0x2c6/0x3a0 kernel/kthread.c:388
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

-> #0 ((console_sem).lock){-...}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2433/0x3b20 kernel/locking/lockdep.c:5137
       lock_acquire kernel/locking/lockdep.c:5754 [inline]
       lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
       down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
       __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:323
       console_trylock+0x73/0x130 kernel/printk/printk.c:2659
       console_trylock_spinning kernel/printk/printk.c:1923 [inline]
       vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2302
       vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
       _printk+0xc8/0x100 kernel/printk/printk.c:2328
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail_ex+0x46b/0x5b0 lib/fault-inject.c:153
       strncpy_from_user+0x38/0x300 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x80/0x180 mm/maccess.c:186
       bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
       ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:225 [inline]
       bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:222
       bpf_prog_6fb7ada547f278f2+0x3d/0x3f
       bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline]
       __bpf_prog_run include/linux/filter.h:651 [inline]
       bpf_prog_run include/linux/filter.h:658 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
       bpf_trace_run4+0x173/0x450 kernel/trace/bpf_trace.c:2422
       __bpf_trace_sched_switch+0x13e/0x180 include/trace/events/sched.h:222
       __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x21f3/0x5af0 kernel/sched/core.c:6685
       preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6865
       preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
       vprintk_emit+0x53e/0x5f0 kernel/printk/printk.c:2304
       vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
       _printk+0xc8/0x100 kernel/printk/printk.c:2328
       validate_nla lib/nlattr.c:410 [inline]
       __nla_validate_parse+0x1897/0x28b0 lib/nlattr.c:631
       __nla_parse+0x40/0x50 lib/nlattr.c:728
       nla_parse_nested_deprecated include/net/netlink.h:1325 [inline]
       ip6_tun_build_state+0x107/0x680 net/ipv4/ip_tunnel_core.c:949
       lwtunnel_build_state+0x1d3/0x670 net/core/lwtunnel.c:135
       fib_nh_common_init+0x149/0x2d0 net/ipv4/fib_semantics.c:604
       fib_nh_init+0xbd/0x450 net/ipv4/fib_semantics.c:630
       fib_create_info+0x24fb/0x4d50 net/ipv4/fib_semantics.c:1497
       fib_table_insert+0x1d7/0x1d70 net/ipv4/fib_trie.c:1236
       inet_rtm_newroute+0x11f/0x200 net/ipv4/fib_frontend.c:903
       rtnetlink_rcv_msg+0x3c7/0xe00 net/core/rtnetlink.c:6560
       netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543
       netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
       netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1367
       netlink_sendmsg+0x8b7/0xd70 net/netlink/af_netlink.c:1908
       sock_sendmsg_nosec net/socket.c:730 [inline]
       __sock_sendmsg+0xd5/0x180 net/socket.c:745
       ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
       ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
       __sys_sendmsg+0x117/0x1e0 net/socket.c:2667
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x63/0x6b

other info that might help us debug this:

Chain exists of:
  (console_sem).lock --> &p->pi_lock --> &rq->__lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rq->__lock);
                               lock(&p->pi_lock);
                               lock(&rq->__lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

3 locks held by syz-executor.3/5651:
 #0: ffffffff8eaa9728 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8eaa9728 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe00 net/core/rtnetlink.c:6557
 #1: ffff8880b993c718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558
 #2: ffffffff8cfabd20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline]
 #2: ffffffff8cfabd20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
 #2: ffffffff8cfabd20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline]
 #2: ffffffff8cfabd20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x107/0x450 kernel/trace/bpf_trace.c:2422

stack backtrace:
CPU: 1 PID: 5651 Comm: syz-executor.3 Not tainted 6.7.0-rc5-syzkaller-01540-g5abde6246522 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 check_noncircular+0x317/0x400 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2433/0x3b20 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
 down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
 __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:323
 console_trylock+0x73/0x130 kernel/printk/printk.c:2659
 console_trylock_spinning kernel/printk/printk.c:1923 [inline]
 vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2302
 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
 _printk+0xc8/0x100 kernel/printk/printk.c:2328
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail_ex+0x46b/0x5b0 lib/fault-inject.c:153
 strncpy_from_user+0x38/0x300 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x80/0x180 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:225 [inline]
 bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:222
 bpf_prog_6fb7ada547f278f2+0x3d/0x3f
 bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline]
 __bpf_prog_run include/linux/filter.h:651 [inline]
 bpf_prog_run include/linux/filter.h:658 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run4+0x173/0x450 kernel/trace/bpf_trace.c:2422
 __bpf_trace_sched_switch+0x13e/0x180 include/trace/events/sched.h:222
 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x21f3/0x5af0 kernel/sched/core.c:6685
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6865
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 vprintk_emit+0x53e/0x5f0 kernel/printk/printk.c:2304
 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
 _printk+0xc8/0x100 kernel/printk/printk.c:2328
 validate_nla lib/nlattr.c:410 [inline]
 __nla_validate_parse+0x1897/0x28b0 lib/nlattr.c:631
 __nla_parse+0x40/0x50 lib/nlattr.c:728
 nla_parse_nested_deprecated include/net/netlink.h:1325 [inline]
 ip6_tun_build_state+0x107/0x680 net/ipv4/ip_tunnel_core.c:949
 lwtunnel_build_state+0x1d3/0x670 net/core/lwtunnel.c:135
 fib_nh_common_init+0x149/0x2d0 net/ipv4/fib_semantics.c:604
 fib_nh_init+0xbd/0x450 net/ipv4/fib_semantics.c:630
 fib_create_info+0x24fb/0x4d50 net/ipv4/fib_semantics.c:1497
 fib_table_insert+0x1d7/0x1d70 net/ipv4/fib_trie.c:1236
 inet_rtm_newroute+0x11f/0x200 net/ipv4/fib_frontend.c:903
 rtnetlink_rcv_msg+0x3c7/0xe00 net/core/rtnetlink.c:6560
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0x8b7/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0xd5/0x180 net/socket.c:745
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7feaae47cba9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007feaaf1840c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007feaae59bf80 RCX: 00007feaae47cba9
RDX: 0000000000000000 RSI: 0000000020000940 RDI: 0000000000000003
RBP: 00007feaaf184120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 000000000000000b R14: 00007feaae59bf80 R15: 00007fffe8890208
 </TASK>
CPU: 1 PID: 5651 Comm: syz-executor.3 Not tainted 6.7.0-rc5-syzkaller-01540-g5abde6246522 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail_ex+0x496/0x5b0 lib/fault-inject.c:153
 strncpy_from_user+0x38/0x300 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x80/0x180 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:225 [inline]
 bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:222
 bpf_prog_6fb7ada547f278f2+0x3d/0x3f
 bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline]
 __bpf_prog_run include/linux/filter.h:651 [inline]
 bpf_prog_run include/linux/filter.h:658 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run4+0x173/0x450 kernel/trace/bpf_trace.c:2422
 __bpf_trace_sched_switch+0x13e/0x180 include/trace/events/sched.h:222
 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x21f3/0x5af0 kernel/sched/core.c:6685
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6865
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 vprintk_emit+0x53e/0x5f0 kernel/printk/printk.c:2304
 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45
 _printk+0xc8/0x100 kernel/printk/printk.c:2328
 validate_nla lib/nlattr.c:410 [inline]
 __nla_validate_parse+0x1897/0x28b0 lib/nlattr.c:631
 __nla_parse+0x40/0x50 lib/nlattr.c:728
 nla_parse_nested_deprecated include/net/netlink.h:1325 [inline]
 ip6_tun_build_state+0x107/0x680 net/ipv4/ip_tunnel_core.c:949
 lwtunnel_build_state+0x1d3/0x670 net/core/lwtunnel.c:135
 fib_nh_common_init+0x149/0x2d0 net/ipv4/fib_semantics.c:604
 fib_nh_init+0xbd/0x450 net/ipv4/fib_semantics.c:630
 fib_create_info+0x24fb/0x4d50 net/ipv4/fib_semantics.c:1497
 fib_table_insert+0x1d7/0x1d70 net/ipv4/fib_trie.c:1236
 inet_rtm_newroute+0x11f/0x200 net/ipv4/fib_frontend.c:903
 rtnetlink_rcv_msg+0x3c7/0xe00 net/core/rtnetlink.c:6560
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0x8b7/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0xd5/0x180 net/socket.c:745
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7feaae47cba9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007feaaf1840c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007feaae59bf80 RCX: 00007feaae47cba9
RDX: 0000000000000000 RSI: 0000000020000940 RDI: 0000000000000003
RBP: 00007feaaf184120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 000000000000000b R14: 00007feaae59bf80 R15: 00007fffe8890208
 </TASK>