WARNING: kernel/printk/printk_ringbuffer.c:1278 at get_data+0x364/0x400, CPU#0: syz-executor.4/14538
Modules linked in:
CPU: 0 UID: 0 PID: 14538 Comm: syz-executor.4 Not tainted 6.18.0-rc2-next-20251023 #1 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:get_data+0x364/0x400
Code: e8 83 e0 07 83 c0 03 38 d0 0f 8c be fe ff ff 84 d2 0f 84 b6 fe ff ff 48 89 ef e8 07 89 5b 00 e9 a9 fe ff ff e8 cd b7 1e 00 90 <0f> 0b 90 45 31 e4 e9 3b ff ff ff e8 bc b7 1e 00 90 0f 0b 90 45 31
RSP: 0018:ffff88806ce08640 EFLAGS: 00010006
RAX: 0000000000010100 RBX: ffff88806ce08758 RCX: ffffffff81556526
RDX: ffff88804d608000 RSI: ffffffff815566f3 RDI: 0000000000000006
RBP: ffff88806ce08720 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff85d30690
R13: 00003fffffffffff R14: 0000000000000000 R15: 0000000000000000
FS: 00007f91f87f3700(0000) GS:ffff8880e53f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f91f87f2f78 CR3: 000000004d4c8000 CR4: 0000000000350ef0
Call Trace:
_prb_read_valid+0x2f3/0x830
prb_read_valid+0x78/0xa0
printk_get_next_message+0x10b/0x570
console_flush_all+0x630/0xb70
console_unlock+0xc2/0x1f0
wake_up_klogd_work_func+0xcf/0x110
irq_work_single+0x128/0x260
irq_work_run_list+0x91/0xc0
update_process_times+0x12f/0x210
tick_nohz_handler+0x414/0x6d0
__hrtimer_run_queues+0x60f/0xac0
hrtimer_interrupt+0x369/0x830
__sysvec_apic_timer_interrupt+0xbb/0x330
sysvec_apic_timer_interrupt+0x34/0x80
asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:handle_softirqs+0x174/0x770
Code: c8 83 83 3c 0a 00 00 01 c7 44 24 20 0a 00 00 00 48 89 44 24 18 65 66 c7 05 0f e3 66 06 00 00 e8 42 be 40 00 fb bb ff ff ff ff <48> c7 c5 c0 c0 c0 85 41 0f bc de 83 c3 01 0f 85 9b 00 00 00 e9 8d
RSP: 0018:ffff88806ce08f78 EFLAGS: 00000202
RAX: 00000000000000f4 RBX: 00000000ffffffff RCX: 0000000000000004
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff813bbd2e
RBP: ffff88804d2efb18 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff86645c57 R11: ffff88806ce37018 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000200 R15: 0000000000000000
__irq_exit_rcu+0xc4/0x100
irq_exit_rcu+0x9/0x20
sysvec_call_function_single+0xa6/0xc0
asm_sysvec_call_function_single+0x1a/0x20
RIP: 0010:dump_stack_lvl+0x115/0x120
Code: fc ff ff 4c 89 e2 31 f6 31 ff e8 86 a7 72 fc e8 f1 b7 9c fc 48 89 ee 31 ff e8 27 7c bc fc e8 c2 80 bc fc e8 6d dd c4 fc fb 5b <5d> 41 5c e9 b3 80 bc fc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffff88804d2efbc8 EFLAGS: 00000202
RAX: 00000000000000f1 RBX: ffffffff8609f220 RCX: 0000000000000040
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff84b79e03
RBP: 0000000000000200 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff86645c57 R11: 0000000000000001 R12: ffffffff85518ce0
R13: ffffffff8609f230 R14: 0000000000000000 R15: 0000000000000000
should_fail_ex+0x4d7/0x5e0
_copy_to_user+0x32/0xd0
simple_read_from_buffer+0xe0/0x180
proc_fail_nth_read+0x18a/0x240
vfs_read+0x1eb/0xc70
ksys_read+0x121/0x240
do_syscall_64+0xbf/0x390
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f91fb29269c
Code: ec 28 48 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 fc ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 48 89 44 24 08 e8 2f fd ff ff 48
RSP: 002b:00007f91f87f3170 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 00007f91fb29269c
RDX: 000000000000000f RSI: 00007f91f87f31e0 RDI: 0000000000000006
RBP: 00007f91f87f31d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffefcf611cf R14: 00007f91f87f3300 R15: 0000000000022000
irq event stamp: 245
hardirqs last enabled at (244): [] handle_softirqs+0x16e/0x770
hardirqs last disabled at (245): [] sysvec_apic_timer_interrupt+0xf/0x80
softirqs last enabled at (236): [] handle_softirqs+0x50c/0x770
softirqs last disabled at (243): [] __irq_exit_rcu+0xc4/0x100
---[ end trace 0000000000000000 ]---
loop2: detected capacity change from 0 to 264192
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 UID: 0 PID: 14542 Comm: syz-executor.5 Tainted: G W 6.18.0-rc2-next-20251023 #1 PREEMPT(voluntary)
Tainted: [W]=WARN
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
dump_stack_lvl+0xfa/0x120
should_fail_ex+0x4d7/0x5e0
should_failslab+0xc2/0x120
__kmalloc_cache_noprof+0x81/0x6b0
kobject_uevent_env+0x22e/0xf90
device_del+0x80a/0xd20
device_unregister+0x15/0x30
bdi_unregister+0x3eb/0x5b0
__del_gendisk+0x9a6/0xb70
del_gendisk+0x142/0x1f0
loop_control_ioctl+0x459/0x640
__x64_sys_ioctl+0x18f/0x210
do_syscall_64+0xbf/0x390
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f71ef4bcb19
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f71eca32188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f71ef5cff60 RCX: 00007f71ef4bcb19
RDX: 0000000000000001 RSI: 0000000000004c81 RDI: 0000000000000003
RBP: 00007f71eca321d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe5e6ed32f R14: 00007f71eca32300 R15: 0000000000022000
EXT4-fs (loop2): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
EXT4-fs (loop2): unmounting filesystem 00000000-0000-0000-0000-000000000000.
----------------
Code disassembly (best guess):
0: c8 83 83 3c enterq $0x8383,$0x3c
4: 0a 00 or (%rax),%al
6: 00 01 add %al,(%rcx)
8: c7 44 24 20 0a 00 00 movl $0xa,0x20(%rsp)
f: 00
10: 48 89 44 24 18 mov %rax,0x18(%rsp)
15: 65 66 c7 05 0f e3 66 movw $0x0,%gs:0x666e30f(%rip) # 0x666e32e
1c: 06 00 00
1f: e8 42 be 40 00 callq 0x40be66
24: fb sti
25: bb ff ff ff ff mov $0xffffffff,%ebx
* 2a: 48 c7 c5 c0 c0 c0 85 mov $0xffffffff85c0c0c0,%rbp <-- trapping instruction
31: 41 0f bc de bsf %r14d,%ebx
35: 83 c3 01 add $0x1,%ebx
38: 0f 85 9b 00 00 00 jne 0xd9
3e: e9 .byte 0xe9
3f: 8d .byte 0x8d