FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 1
======================================================
WARNING: possible circular locking dependency detected
6.1.129-syzkaller #0 Not tainted
------------------------------------------------------
syz.5.257/5654 is trying to acquire lock:
ffffffff8d20a538 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:139

but task is already holding lock:
ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&rq->__lock){-.-.}-{2:2}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:378
       raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
       raw_spin_rq_lock kernel/sched/sched.h:1355 [inline]
       rq_lock kernel/sched/sched.h:1645 [inline]
       task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11886
       sched_cgroup_fork+0x374/0x400 kernel/sched/core.c:4684
       copy_process+0x2482/0x40a0 kernel/fork.c:2383
       kernel_clone+0x222/0x920 kernel/fork.c:2681
       user_mode_thread+0x140/0x1b0 kernel/fork.c:2757
       rest_init+0x23/0x300 init/main.c:698
       start_kernel+0x0/0x53f init/main.c:893
       start_kernel+0x496/0x53f init/main.c:1140
       secondary_startup_64_no_verify+0xcf/0xdb

-> #1 (&p->pi_lock){-.-.}-{2:2}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       try_to_wake_up+0xad/0x1250 kernel/sched/core.c:4110
       up+0x6e/0x90 kernel/locking/semaphore.c:191
       __up_console_sem+0x11a/0x1e0 kernel/printk/printk.c:260
       __console_unlock kernel/printk/printk.c:2697 [inline]
       console_unlock+0x591/0x7c0 kernel/printk/printk.c:2908
       vprintk_emit+0x523/0x740 kernel/printk/printk.c:2303
       _printk+0xd1/0x111 kernel/printk/printk.c:2328
       batadv_check_known_mac_addr+0x2b6/0x400 net/batman-adv/hard-interface.c:527
       batadv_hard_if_event+0x308/0x1550 net/batman-adv/hard-interface.c:992
       notifier_call_chain kernel/notifier.c:87 [inline]
       raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455
       call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
       call_netdevice_notifiers net/core/dev.c:2022 [inline]
       dev_set_mac_address+0x345/0x460 net/core/dev.c:8855
       dev_set_mac_address_user+0x2d/0x50 net/core/dev.c:8869
       do_setlink+0x914/0x4060 net/core/rtnetlink.c:2785
       __rtnl_newlink net/core/rtnetlink.c:3605 [inline]
       rtnl_newlink+0x1736/0x2060 net/core/rtnetlink.c:3652
       rtnetlink_rcv_msg+0x822/0x1000 net/core/rtnetlink.c:6150
       netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2493
       netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
       netlink_unicast+0x7e2/0x970 net/netlink/af_netlink.c:1337
       netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1859
       sock_sendmsg_nosec net/socket.c:718 [inline]
       __sock_sendmsg net/socket.c:730 [inline]
       __sys_sendto+0x480/0x600 net/socket.c:2153
       __do_sys_sendto net/socket.c:2165 [inline]
       __se_sys_sendto net/socket.c:2161 [inline]
       __x64_sys_sendto+0xda/0xf0 net/socket.c:2161
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 ((console_sem).lock){-...}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:139
       __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:243
       console_trylock kernel/printk/printk.c:2650 [inline]
       console_trylock_spinning kernel/printk/printk.c:1896 [inline]
       vprintk_emit+0x1ee/0x740 kernel/printk/printk.c:2302
       _printk+0xd1/0x111 kernel/printk/printk.c:2328
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail_ex+0x387/0x4d0 lib/fault-inject.c:147
       strncpy_from_user+0x32/0x360 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:186
       bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline]
       ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline]
       bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210
       bpf_prog_bc7c5c6b9645592f+0x35/0x37
       bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline]
       __bpf_prog_run include/linux/filter.h:603 [inline]
       bpf_prog_run include/linux/filter.h:610 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline]
       bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2325
       __traceiter_sched_switch+0x91/0xc0 include/trace/events/sched.h:222
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x2128/0x4570 kernel/sched/core.c:6557
       preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6729
       preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6753
       preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
       percpu_up_read include/linux/percpu-rwsem.h:121 [inline]
       __sb_end_write include/linux/fs.h:1886 [inline]
       file_end_write+0x209/0x250 include/linux/fs.h:3029
       vfs_write+0x6cf/0xbc0 fs/read_write.c:592
       ksys_write+0x19c/0x2c0 fs/read_write.c:637
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

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.5.257/5654:
 #0: ffff888027f4dc68 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ba/0x360 fs/file.c:1032
 #1: ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
 #2: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #2: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #2: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2283 [inline]
 #2: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x16a/0x470 kernel/trace/bpf_trace.c:2325

stack backtrace:
CPU: 0 PID: 5654 Comm: syz.5.257 Not tainted 6.1.129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:139
 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:243
 console_trylock kernel/printk/printk.c:2650 [inline]
 console_trylock_spinning kernel/printk/printk.c:1896 [inline]
 vprintk_emit+0x1ee/0x740 kernel/printk/printk.c:2302
 _printk+0xd1/0x111 kernel/printk/printk.c:2328
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail_ex+0x387/0x4d0 lib/fault-inject.c:147
 strncpy_from_user+0x32/0x360 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline]
 ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline]
 bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210
 bpf_prog_bc7c5c6b9645592f+0x35/0x37
 bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline]
 bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2325
 __traceiter_sched_switch+0x91/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x2128/0x4570 kernel/sched/core.c:6557
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6729
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6753
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 percpu_up_read include/linux/percpu-rwsem.h:121 [inline]
 __sb_end_write include/linux/fs.h:1886 [inline]
 file_end_write+0x209/0x250 include/linux/fs.h:3029
 vfs_write+0x6cf/0xbc0 fs/read_write.c:592
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe1fd58bc1f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fe1fd3bd030 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fe1fd58bc1f
RDX: 0000000000000001 RSI: 00007fe1fd3bd090 RDI: 0000000000000005
RBP: 00007fe1fd3bd090 R08: 0000000000000000 R09: 00007fe1fd3bcdf7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 0000000000000001 R14: 00007fe1fd7a6160 R15: 00007ffe5d6f9018
 </TASK>
CPU: 0 PID: 5654 Comm: syz.5.257 Not tainted 6.1.129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail_ex+0x3a6/0x4d0 lib/fault-inject.c:147
 strncpy_from_user+0x32/0x360 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:204 [inline]
 ____bpf_probe_read_user_str kernel/trace/bpf_trace.c:213 [inline]
 bpf_probe_read_user_str+0x26/0x70 kernel/trace/bpf_trace.c:210
 bpf_prog_bc7c5c6b9645592f+0x35/0x37
 bpf_dispatcher_nop_func include/linux/bpf.h:1000 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2284 [inline]
 bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2325
 __traceiter_sched_switch+0x91/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x2128/0x4570 kernel/sched/core.c:6557
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6729
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6753
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 percpu_up_read include/linux/percpu-rwsem.h:121 [inline]
 __sb_end_write include/linux/fs.h:1886 [inline]
 file_end_write+0x209/0x250 include/linux/fs.h:3029
 vfs_write+0x6cf/0xbc0 fs/read_write.c:592
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe1fd58bc1f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fe1fd3bd030 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fe1fd58bc1f
RDX: 0000000000000001 RSI: 00007fe1fd3bd090 RDI: 0000000000000005
RBP: 00007fe1fd3bd090 R08: 0000000000000000 R09: 00007fe1fd3bcdf7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 0000000000000001 R14: 00007fe1fd7a6160 R15: 00007ffe5d6f9018
 </TASK>