FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
5.15.178-syzkaller #0 Not tainted
------------------------------------------------------
syz.6.745/7478 is trying to acquire lock:
ffffffff8c9fc538 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138

but task is already holding lock:
ffff8880b8f3a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&rq->__lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:368
       raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
       raw_spin_rq_lock kernel/sched/sched.h:1326 [inline]
       rq_lock kernel/sched/sched.h:1621 [inline]
       task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11488
       sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4463
       copy_process+0x224a/0x3ef0 kernel/fork.c:2319
       kernel_clone+0x210/0x960 kernel/fork.c:2603
       kernel_thread+0x168/0x1e0 kernel/fork.c:2655
       rest_init+0x21/0x330 init/main.c:706
       start_kernel+0x48c/0x540 init/main.c:1140
       secondary_startup_64_no_verify+0xb1/0xbb

-> #1 (&p->pi_lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __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+0xae/0x1300 kernel/sched/core.c:4027
       up+0x6e/0x90 kernel/locking/semaphore.c:190
       __up_console_sem+0x11a/0x1e0 kernel/printk/printk.c:256
       console_unlock+0x1145/0x12b0 kernel/printk/printk.c:2760
       vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
       _printk+0xd1/0x120 kernel/printk/printk.c:2299
       __ext4_msg+0x1fc/0x210 fs/ext4/super.c:917
       parse_options+0x2b50/0x32b0 fs/ext4/super.c:2505
       ext4_fill_super+0x236e/0xa110 fs/ext4/super.c:4177
       mount_bdev+0x2c9/0x3f0 fs/super.c:1400
       legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
       vfs_get_tree+0x88/0x270 fs/super.c:1530
       do_new_mount+0x2ba/0xb40 fs/namespace.c:3012
       do_mount fs/namespace.c:3355 [inline]
       __do_sys_mount fs/namespace.c:3563 [inline]
       __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3540
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 ((console_sem).lock){-.-.}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __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:138
       __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239
       console_trylock kernel/printk/printk.c:2575 [inline]
       console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867
       vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273
       _printk+0xd1/0x120 kernel/printk/printk.c:2299
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail+0x36c/0x4c0 lib/fault-inject.c:146
       strncpy_from_user+0x32/0x370 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:295
       bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:194 [inline]
       ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:300 [inline]
       bpf_probe_read_compat_str+0xe4/0x180 kernel/trace/bpf_trace.c:296
       bpf_prog_c1796171ffc7efef+0x35/0x920
       bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
       __bpf_prog_run include/linux/filter.h:628 [inline]
       bpf_prog_run include/linux/filter.h:635 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
       bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1916
       __traceiter_sched_switch+0x7d/0xb0 include/trace/events/sched.h:220
       trace_sched_switch include/trace/events/sched.h:220 [inline]
       __schedule+0x1e8d/0x45b0 kernel/sched/core.c:6370
       preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
       irqentry_exit+0x53/0x80 kernel/entry/common.c:432
       asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681
       tomoyo_socket_sendmsg_permission+0x0/0x410
       security_socket_sendmsg+0x6d/0xa0 security/security.c:2252
       __sock_sendmsg net/socket.c:713 [inline]
       __sys_sendto+0x4d4/0x720 net/socket.c:2063
       __do_sys_sendto net/socket.c:2075 [inline]
       __se_sys_sendto net/socket.c:2071 [inline]
       __x64_sys_sendto+0xda/0xf0 net/socket.c:2071
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

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 ***

2 locks held by syz.6.745/7478:
 #0: ffff8880b8f3a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffffffff8cb1fce0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311

stack backtrace:
CPU: 1 PID: 7478 Comm: syz.6.745 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __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:138
 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239
 console_trylock kernel/printk/printk.c:2575 [inline]
 console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867
 vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail+0x36c/0x4c0 lib/fault-inject.c:146
 strncpy_from_user+0x32/0x370 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:295
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:194 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:300 [inline]
 bpf_probe_read_compat_str+0xe4/0x180 kernel/trace/bpf_trace.c:296
 bpf_prog_c1796171ffc7efef+0x35/0x920
 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1916
 __traceiter_sched_switch+0x7d/0xb0 include/trace/events/sched.h:220
 trace_sched_switch include/trace/events/sched.h:220 [inline]
 __schedule+0x1e8d/0x45b0 kernel/sched/core.c:6370
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681
RIP: 0010:tomoyo_socket_sendmsg_permission+0x0/0x410 security/tomoyo/network.c:760
Code: 89 d9 80 e1 07 fe c1 38 c1 0f 8c 5d ff ff ff 48 89 df e8 b3 90 f8 fd e9 50 ff ff ff e8 29 72 6d 06 66 0f 1f 84 00 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00
RSP: 0018:ffffc9000343fca0 EFLAGS: 00000293
RAX: ffffffff83d21d62 RBX: ffffffff8c5ce3a8 RCX: ffff888021e4bb80
RDX: 0000000000000218 RSI: ffffc9000343fde0 RDI: ffff888075683600
RBP: ffffffff8c5ce3c0 R08: ffffffff884ca647 R09: fffff52000687faa
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888075683600
R13: dffffc0000000000 R14: 0000000000000218 R15: ffffc9000343fde0
 security_socket_sendmsg+0x6d/0xa0 security/security.c:2252
 __sock_sendmsg net/socket.c:713 [inline]
 __sys_sendto+0x4d4/0x720 net/socket.c:2063
 __do_sys_sendto net/socket.c:2075 [inline]
 __se_sys_sendto net/socket.c:2071 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2071
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5c9404ede9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5c91e76038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f5c94268160 RCX: 00007f5c9404ede9
RDX: 0000000000000218 RSI: 0000000000000000 RDI: 000000000000000a
RBP: 00007f5c91e76090 R08: 0000400000e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f5c94268160 R15: 00007ffcbf4223b8
 </TASK>
CPU: 1 PID: 7478 Comm: syz.6.745 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail+0x38a/0x4c0 lib/fault-inject.c:146
 strncpy_from_user+0x32/0x370 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x6c/0x130 mm/maccess.c:295
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:194 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:300 [inline]
 bpf_probe_read_compat_str+0xe4/0x180 kernel/trace/bpf_trace.c:296
 bpf_prog_c1796171ffc7efef+0x35/0x920
 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1916
 __traceiter_sched_switch+0x7d/0xb0 include/trace/events/sched.h:220
 trace_sched_switch include/trace/events/sched.h:220 [inline]
 __schedule+0x1e8d/0x45b0 kernel/sched/core.c:6370
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681
RIP: 0010:tomoyo_socket_sendmsg_permission+0x0/0x410 security/tomoyo/network.c:760
Code: 89 d9 80 e1 07 fe c1 38 c1 0f 8c 5d ff ff ff 48 89 df e8 b3 90 f8 fd e9 50 ff ff ff e8 29 72 6d 06 66 0f 1f 84 00 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00
RSP: 0018:ffffc9000343fca0 EFLAGS: 00000293
RAX: ffffffff83d21d62 RBX: ffffffff8c5ce3a8 RCX: ffff888021e4bb80
RDX: 0000000000000218 RSI: ffffc9000343fde0 RDI: ffff888075683600
RBP: ffffffff8c5ce3c0 R08: ffffffff884ca647 R09: fffff52000687faa
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888075683600
R13: dffffc0000000000 R14: 0000000000000218 R15: ffffc9000343fde0
 security_socket_sendmsg+0x6d/0xa0 security/security.c:2252
 __sock_sendmsg net/socket.c:713 [inline]
 __sys_sendto+0x4d4/0x720 net/socket.c:2063
 __do_sys_sendto net/socket.c:2075 [inline]
 __se_sys_sendto net/socket.c:2071 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2071
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5c9404ede9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5c91e76038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f5c94268160 RCX: 00007f5c9404ede9
RDX: 0000000000000218 RSI: 0000000000000000 RDI: 000000000000000a
RBP: 00007f5c91e76090 R08: 0000400000e68000 R09: 0000000000000010
R10: 00000000200007fd R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f5c94268160 R15: 00007ffcbf4223b8
 </TASK>
----------------
Code disassembly (best guess):
   0:	89 d9                	mov    %ebx,%ecx
   2:	80 e1 07             	and    $0x7,%cl
   5:	fe c1                	inc    %cl
   7:	38 c1                	cmp    %al,%cl
   9:	0f 8c 5d ff ff ff    	jl     0xffffff6c
   f:	48 89 df             	mov    %rbx,%rdi
  12:	e8 b3 90 f8 fd       	call   0xfdf890ca
  17:	e9 50 ff ff ff       	jmp    0xffffff6c
  1c:	e8 29 72 6d 06       	call   0x66d724a
  21:	66 0f 1f 84 00 00 00 	nopw   0x0(%rax,%rax,1)
  28:	00 00
* 2a:	55                   	push   %rbp <-- trapping instruction
  2b:	48 89 e5             	mov    %rsp,%rbp
  2e:	41 57                	push   %r15
  30:	41 56                	push   %r14
  32:	41 55                	push   %r13
  34:	41 54                	push   %r12
  36:	53                   	push   %rbx
  37:	48 83 e4 e0          	and    $0xffffffffffffffe0,%rsp
  3b:	48                   	rex.W
  3c:	81                   	.byte 0x81
  3d:	ec                   	in     (%dx),%al
  3e:	e0 00                	loopne 0x40