FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
5.15.165-syzkaller #0 Not tainted
------------------------------------------------------
syz.2.713/6873 is trying to acquire lock:
ffffffff8c7fc438 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138

but task is already holding lock:
ffff8880b9a3a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa8/0x140 kernel/sched/core.c:483

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:11484
       sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4463
       copy_process+0x224a/0x3ef0 kernel/fork.c:2320
       kernel_clone+0x210/0x960 kernel/fork.c:2604
       kernel_thread+0x168/0x1e0 kernel/fork.c:2656
       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
       exfat_msg+0x136/0x180 fs/exfat/misc.c:61
       exfat_load_upcase_table fs/exfat/nls.c:702 [inline]
       exfat_create_upcase_table+0xcbe/0xfa0 fs/exfat/nls.c:784
       __exfat_fill_super fs/exfat/super.c:588 [inline]
       exfat_fill_super+0x1249/0x2d70 fs/exfat/super.c:644
       get_tree_bdev+0x3fe/0x620 fs/super.c:1323
       vfs_get_tree+0x88/0x270 fs/super.c:1528
       do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
       do_mount fs/namespace.c:3348 [inline]
       __do_sys_mount fs/namespace.c:3556 [inline]
       __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
       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+0x35/0x7c4
       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:1880 [inline]
       bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
       __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:643
       __begin_current_label_crit_section security/apparmor/include/cred.h:142 [inline]
       common_file_perm+0x112/0x1d0 security/apparmor/lsm.c:474
       security_file_permission+0x65/0xa0 security/security.c:1521
       rw_verify_area fs/read_write.c:389 [inline]
       do_sendfile+0x2c7/0x1000 fs/read_write.c:1203
       __do_sys_sendfile64 fs/read_write.c:1317 [inline]
       __se_sys_sendfile64+0x178/0x1e0 fs/read_write.c:1303
       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.2.713/6873:
 #0: ffff8880b9a3a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa8/0x140 kernel/sched/core.c:483
 #1: ffffffff8c91fbe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311

stack backtrace:
CPU: 1 PID: 6873 Comm: syz.2.713 Not tainted 5.15.165-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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+0x35/0x7c4
 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:1880 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
 __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:643
RIP: 0010:__begin_current_label_crit_section security/apparmor/include/cred.h:142 [inline]
RIP: 0010:common_file_perm+0x112/0x1d0 security/apparmor/lsm.c:474
Code: 48 89 ef e8 40 a6 fd fd 4c 8b 7d 00 4d 85 ff 0f 84 b0 00 00 00 e8 5e dd b3 fd 49 8d 5f 40 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 14 a6 fd fd 48 8b 1b bd 00 08 00 00 be 00 08 00
RSP: 0018:ffffc90002dd7c88 EFLAGS: 00000246
RAX: 1ffff110023baa5e RBX: ffff888011dd52f0 RCX: ffff88801cb70000
RDX: 0000000000000000 RSI: ffff88801907db80 RDI: ffffffff8ad35580
RBP: ffff88802375a848 R08: ffffffff81d5b510 R09: fffffbfff1bd2a56
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88801907db80 R14: dffffc0000000000 R15: ffff888011dd52b0
 security_file_permission+0x65/0xa0 security/security.c:1521
 rw_verify_area fs/read_write.c:389 [inline]
 do_sendfile+0x2c7/0x1000 fs/read_write.c:1203
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x178/0x1e0 fs/read_write.c:1303
 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: 0033:0x7f09a58dde79
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:00007f09a3d18038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f09a5a7a130 RCX: 00007f09a58dde79
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000006
RBP: 00007f09a3d18090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000020000023893 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f09a5a7a130 R15: 00007ffc3c362c38
 </TASK>
CPU: 1 PID: 6873 Comm: syz.2.713 Not tainted 5.15.165-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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+0x35/0x7c4
 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:1880 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
 __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:643
RIP: 0010:__begin_current_label_crit_section security/apparmor/include/cred.h:142 [inline]
RIP: 0010:common_file_perm+0x112/0x1d0 security/apparmor/lsm.c:474
Code: 48 89 ef e8 40 a6 fd fd 4c 8b 7d 00 4d 85 ff 0f 84 b0 00 00 00 e8 5e dd b3 fd 49 8d 5f 40 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 14 a6 fd fd 48 8b 1b bd 00 08 00 00 be 00 08 00
RSP: 0018:ffffc90002dd7c88 EFLAGS: 00000246
RAX: 1ffff110023baa5e RBX: ffff888011dd52f0 RCX: ffff88801cb70000
RDX: 0000000000000000 RSI: ffff88801907db80 RDI: ffffffff8ad35580
RBP: ffff88802375a848 R08: ffffffff81d5b510 R09: fffffbfff1bd2a56
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88801907db80 R14: dffffc0000000000 R15: ffff888011dd52b0
 security_file_permission+0x65/0xa0 security/security.c:1521
 rw_verify_area fs/read_write.c:389 [inline]
 do_sendfile+0x2c7/0x1000 fs/read_write.c:1203
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x178/0x1e0 fs/read_write.c:1303
 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: 0033:0x7f09a58dde79
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:00007f09a3d18038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f09a5a7a130 RCX: 00007f09a58dde79
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000006
RBP: 00007f09a3d18090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000020000023893 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 00007f09a5a7a130 R15: 00007ffc3c362c38
 </TASK>
----------------
Code disassembly (best guess):
   0:	48 89 ef             	mov    %rbp,%rdi
   3:	e8 40 a6 fd fd       	call   0xfdfda648
   8:	4c 8b 7d 00          	mov    0x0(%rbp),%r15
   c:	4d 85 ff             	test   %r15,%r15
   f:	0f 84 b0 00 00 00    	je     0xc5
  15:	e8 5e dd b3 fd       	call   0xfdb3dd78
  1a:	49 8d 5f 40          	lea    0x40(%r15),%rbx
  1e:	48 89 d8             	mov    %rbx,%rax
  21:	48 c1 e8 03          	shr    $0x3,%rax
  25:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
* 2a:	74 08                	je     0x34 <-- trapping instruction
  2c:	48 89 df             	mov    %rbx,%rdi
  2f:	e8 14 a6 fd fd       	call   0xfdfda648
  34:	48 8b 1b             	mov    (%rbx),%rbx
  37:	bd 00 08 00 00       	mov    $0x800,%ebp
  3c:	be                   	.byte 0xbe
  3d:	00 08                	add    %cl,(%rax)