random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) ================================ WARNING: inconsistent lock state 4.17.0-rc2+ #14 Not tainted -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. syzkaller151432/4525 [HC1[1]:SC0[0]:HE0:SE1] takes: (ptrval) (fs_reclaim){?.+.}, at: fs_reclaim_acquire.part.82+0x0/0x30 mm/page_alloc.c:463 {HARDIRQ-ON-W} state was registered at: lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 fs_reclaim_acquire.part.82+0x24/0x30 mm/page_alloc.c:3739 fs_reclaim_acquire+0x14/0x20 mm/page_alloc.c:3740 slab_pre_alloc_hook mm/slab.h:418 [inline] slab_alloc_node mm/slab.c:3299 [inline] kmem_cache_alloc_node_trace+0x39/0x770 mm/slab.c:3661 kmalloc_node include/linux/slab.h:550 [inline] kzalloc_node include/linux/slab.h:712 [inline] alloc_worker+0xbd/0x2e0 kernel/workqueue.c:1704 init_rescuer.part.25+0x1f/0x190 kernel/workqueue.c:4000 init_rescuer kernel/workqueue.c:3997 [inline] workqueue_init+0x51f/0x7d0 kernel/workqueue.c:5732 kernel_init_freeable+0x2ad/0x58e init/main.c:1115 kernel_init+0x11/0x1b3 init/main.c:1053 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 irq event stamp: 927456 hardirqs last enabled at (927455): [] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (927455): [] _raw_spin_unlock_irq+0x27/0x70 kernel/locking/spinlock.c:192 hardirqs last disabled at (927456): [] interrupt_entry+0xb5/0xf0 arch/x86/entry/entry_64.S:625 softirqs last enabled at (927430): [] spin_unlock_bh include/linux/spinlock.h:355 [inline] softirqs last enabled at (927430): [] wb_queue_work+0x302/0x6e0 fs/fs-writeback.c:203 softirqs last disabled at (927426): [] spin_lock_bh include/linux/spinlock.h:315 [inline] softirqs last disabled at (927426): [] wb_queue_work+0x117/0x6e0 fs/fs-writeback.c:195 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(fs_reclaim); lock(fs_reclaim); *** DEADLOCK *** 1 lock held by syzkaller151432/4525: #0: (ptrval) (&type->s_umount_key#29){++++}, at: __do_sys_syncfs fs/sync.c:170 [inline] #0: (ptrval) (&type->s_umount_key#29){++++}, at: __se_sys_syncfs fs/sync.c:160 [inline] #0: (ptrval) (&type->s_umount_key#29){++++}, at: __x64_sys_syncfs+0xb6/0x120 fs/sync.c:160 stack backtrace: CPU: 0 PID: 4525 Comm: syzkaller151432 Not tainted 4.17.0-rc2+ #14 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_usage_bug.cold.59+0x320/0x41a kernel/locking/lockdep.c:2542 valid_state kernel/locking/lockdep.c:2555 [inline] mark_lock_irq kernel/locking/lockdep.c:2749 [inline] mark_lock+0x1034/0x19e0 kernel/locking/lockdep.c:3147 mark_irqflags kernel/locking/lockdep.c:3022 [inline] __lock_acquire+0x1595/0x5140 kernel/locking/lockdep.c:3388 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 fs_reclaim_acquire.part.82+0x24/0x30 mm/page_alloc.c:3739 fs_reclaim_acquire+0x14/0x20 mm/page_alloc.c:3740 slab_pre_alloc_hook mm/slab.h:418 [inline] slab_alloc mm/slab.c:3378 [inline] __do_kmalloc mm/slab.c:3716 [inline] __kmalloc+0x45/0x760 mm/slab.c:3727 kmalloc_array include/linux/slab.h:631 [inline] kcalloc include/linux/slab.h:642 [inline] numa_crng_init drivers/char/random.c:798 [inline] crng_reseed+0x427/0x920 drivers/char/random.c:923 credit_entropy_bits+0x98d/0xa30 drivers/char/random.c:708 add_interrupt_randomness+0x494/0x860 drivers/char/random.c:1254 handle_irq_event_percpu+0xf9/0x1c0 kernel/irq/handle.c:191 handle_irq_event+0xa7/0x135 kernel/irq/handle.c:206 handle_edge_irq+0x20f/0x870 kernel/irq/chip.c:791 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x18c/0x2e7 arch/x86/kernel/irq_64.c:77 do_IRQ+0x78/0x190 arch/x86/kernel/irq.c:245 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:642 RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:793 [inline] RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] RIP: 0010:_raw_spin_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:192 RSP: 0018:ffff8801ab34f6b0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffda RAX: dffffc0000000000 RBX: ffff8801dae2c580 RCX: 1ffff10035f7393b RDX: 1ffffffff11a315f RSI: ffff8801afb9c9b8 RDI: ffffffff88d18af8 RBP: ffff8801ab34f6b8 R08: ffff8801afb9c9b8 R09: 0000000000000006 R10: ffff8801afb9c180 R11: 0000000000000000 R12: ffff8801afb9c180 R13: ffff8801d2136600 R14: ffff8801b0312c80 R15: ffff8801afb9c180 finish_lock_switch kernel/sched/core.c:2603 [inline] finish_task_switch+0x1ca/0x810 kernel/sched/core.c:2701 context_switch kernel/sched/core.c:2851 [inline] __schedule+0x809/0x1e30 kernel/sched/core.c:3490 preempt_schedule_common+0x22/0x60 kernel/sched/core.c:3629 _cond_resched+0x1d/0x30 kernel/sched/core.c:4978 __wait_for_common kernel/sched/completion.c:99 [inline] wait_for_common_io kernel/sched/completion.c:121 [inline] wait_for_completion_io+0xa7/0x870 kernel/sched/completion.c:169 submit_bio_wait+0x13c/0x1e0 block/bio.c:947 blkdev_issue_flush+0x226/0x320 block/blk-flush.c:548 ext4_sync_fs+0x604/0xaf0 fs/ext4/super.c:4895 __sync_filesystem fs/sync.c:39 [inline] sync_filesystem+0x265/0x310 fs/sync.c:67 __do_sys_syncfs fs/sync.c:171 [inline] __se_sys_syncfs fs/sync.c:160 [inline] __x64_sys_syncfs+0xbe/0x120 fs/sync.c:160 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440069 RSP: 002b:00007ffd92dff978 EFLAGS: 00000246 ORIG_RAX: 0000000000000132 RAX: ffffffffffffffda RBX: 00007ffd92dff980 RCX: 0000000000440069 RDX: 0000000000400ae0 RSI: ffffffffffffffff RDI: 00000000000003ff RBP: 0000000020000380 R08: 000000000000000f R09: 65732f636f72702f R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004a1528 R13: 00000000004a15f4 R14: 00000000000077f0 R15: 0000000000000000 BUG: sleeping function called from invalid context at mm/slab.h:421 in_atomic(): 1, irqs_disabled(): 1, pid: 4525, name: syzkaller151432 INFO: lockdep is turned off. irq event stamp: 927456 hardirqs last enabled at (927455): [] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (927455): [] _raw_spin_unlock_irq+0x27/0x70 kernel/locking/spinlock.c:192 hardirqs last disabled at (927456): [] interrupt_entry+0xb5/0xf0 arch/x86/entry/entry_64.S:625 softirqs last enabled at (927430): [] spin_unlock_bh include/linux/spinlock.h:355 [inline] softirqs last enabled at (927430): [] wb_queue_work+0x302/0x6e0 fs/fs-writeback.c:203 softirqs last disabled at (927426): [] spin_lock_bh include/linux/spinlock.h:315 [inline] softirqs last disabled at (927426): [] wb_queue_work+0x117/0x6e0 fs/fs-writeback.c:195 CPU: 0 PID: 4525 Comm: syzkaller151432 Not tainted 4.17.0-rc2+ #14 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 ___might_sleep.cold.87+0x11f/0x13a kernel/sched/core.c:6188 __might_sleep+0x95/0x190 kernel/sched/core.c:6141 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3378 [inline] __do_kmalloc mm/slab.c:3716 [inline] __kmalloc+0x2b9/0x760 mm/slab.c:3727 kmalloc_array include/linux/slab.h:631 [inline] kcalloc include/linux/slab.h:642 [inline] numa_crng_init drivers/char/random.c:798 [inline] crng_reseed+0x427/0x920 drivers/char/random.c:923 credit_entropy_bits+0x98d/0xa30 drivers/char/random.c:708 add_interrupt_randomness+0x494/0x860 drivers/char/random.c:1254 handle_irq_event_percpu+0xf9/0x1c0 kernel/irq/handle.c:191 handle_irq_event+0xa7/0x135 kernel/irq/handle.c:206 handle_edge_irq+0x20f/0x870 kernel/irq/chip.c:791 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x18c/0x2e7 arch/x86/kernel/irq_64.c:77 do_IRQ+0x78/0x190 arch/x86/kernel/irq.c:245 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:642 RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:793 [inline] RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] RIP: 0010:_raw_spin_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:192 RSP: 0018:ffff8801ab34f6b0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffda RAX: dffffc0000000000 RBX: ffff8801dae2c580 RCX: 1ffff10035f7393b RDX: 1ffffffff11a315f RSI: ffff8801afb9c9b8 RDI: ffffffff88d18af8 RBP: ffff8801ab34f6b8 R08: ffff8801afb9c9b8 R09: 0000000000000006 R10: ffff8801afb9c180 R11: 0000000000000000 R12: ffff8801afb9c180 R13: ffff8801d2136600 R14: ffff8801b0312c80 R15: ffff8801afb9c180 finish_lock_switch kernel/sched/core.c:2603 [inline] finish_task_switch+0x1ca/0x810 kernel/sched/core.c:2701 context_switch kernel/sched/core.c:2851 [inline] __schedule+0x809/0x1e30 kernel/sched/core.c:3490 preempt_schedule_common+0x22/0x60 kernel/sched/core.c:3629 _cond_resched+0x1d/0x30 kernel/sched/core.c:4978 __wait_for_common kernel/sched/completion.c:99 [inline] wait_for_common_io kernel/sched/completion.c:121 [inline] wait_for_completion_io+0xa7/0x870 kernel/sched/completion.c:169 submit_bio_wait+0x13c/0x1e0 block/bio.c:947 blkdev_issue_flush+0x226/0x320 block/blk-flush.c:548 ext4_sync_fs+0x604/0xaf0 fs/ext4/super.c:4895 __sync_filesystem fs/sync.c:39 [inline] sync_filesystem+0x265/0x310 fs/sync.c:67 __do_sys_syncfs fs/sync.c:171 [inline] __se_sys_syncfs fs/sync.c:160 [inline] __x64_sys_syncfs+0xbe/0x120 fs/sync.c:160 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440069 RSP: 002b:00007ffd92dff978 EFLAGS: 00000246 ORIG_RAX: 0000000000000132 RAX: ffffffffffffffda RBX: 00007ffd92dff980 RCX: 0000000000440069 RDX: 0000000000400ae0 RSI: ffffffffffffffff RDI: 00000000000003ff RBP: 0000000020000380 R08: 000000000000000f R09: 65732f636f72702f R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004a1528 R13: 00000000004a15f4 R14: 00000000000077f0 R15: 0000000000000000 random: crng init done