Hello, syzbot found the following issue on: HEAD commit: 787af64d05cd mm: page_alloc: validate buddy before check i.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=109c0687700000 kernel config: https://syzkaller.appspot.com/x/.config?x=3daed5742799b46b dashboard link: https://syzkaller.appspot.com/bug?extid=d17750670998d5d4f5ec compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d17750670998d5d4f5ec@xxxxxxxxxxxxxxxxxxxxxxxxx BUG: sleeping function called from invalid context at block/blk-sysfs.c:766 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 3123, name: udevd preempt_count: 100, expected: 0 RCU nest depth: 2, expected: 0 4 locks held by udevd/3123: #0: ffffffff8c592858 (tomoyo_ss){....}-{0:0}, at: tomoyo_check_open_permission+0xe8/0x380 security/tomoyo/file.c:761 #1: ffffffff8bd7f3e0 (rcu_read_lock){....}-{1:2}, at: prepend_path+0x0/0xea0 fs/d_path.c:368 #2: ffffffff8bd7f3e0 (rcu_read_lock){....}-{1:2}, at: need_seqretry include/linux/seqlock.h:1158 [inline] #2: ffffffff8bd7f3e0 (rcu_read_lock){....}-{1:2}, at: prepend_path+0x25f/0xea0 fs/d_path.c:182 #3: ffffffff8bd7f2c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2524 [inline] #3: ffffffff8bd7f2c0 (rcu_callback){....}-{0:0}, at: rcu_core+0x73d/0x1880 kernel/rcu/tree.c:2786 <IRQ> kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:753 blkg_free.part.0+0x112/0x1f0 block/blk-cgroup.c:86 blkg_free block/blk-cgroup.c:78 [inline] __blkg_release+0x105/0x160 block/blk-cgroup.c:102 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0x7b1/0x1880 kernel/rcu/tree.c:2786 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: 48 89 ef 5d e9 f1 90 4a 00 5d be 03 00 00 00 e9 36 66 74 02 66 0f 1f 44 00 00 48 8b be a8 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 <65> 8b 05 c9 a2 8a 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc900030ff5c8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000000 RDX: ffff888021002280 RSI: ffffffff81df460e RDI: 0000000000000003 RBP: ffffc900030ff6d8 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff81df4604 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88801ab435d0 R14: dffffc0000000000 R15: dffffc0000000000 __seqprop_spinlock_sequence include/linux/seqlock.h:277 [inline] read_seqbegin include/linux/seqlock.h:840 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1144 [inline] prepend_path+0x3b4/0xea0 fs/d_path.c:170 d_absolute_path+0xef/0x1a0 fs/d_path.c:233 tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline] tomoyo_file_open+0x9d/0xc0 security/tomoyo/tomoyo.c:306 security_file_open+0x45/0xb0 security/security.c:1651 do_dentry_open+0x349/0x11e0 fs/open.c:811 do_open fs/namei.c:3476 [inline] path_openat+0x1c71/0x2910 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4c0 fs/open.c:1213 do_sys_open fs/open.c:1229 [inline] __do_sys_openat fs/open.c:1245 [inline] __se_sys_openat fs/open.c:1240 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1240 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa17d125697 Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f RSP: 002b:00007ffeed1068f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000564cae660160 RCX: 00007fa17d125697 RDX: 0000000000080000 RSI: 00007ffeed106a28 RDI: 00000000ffffff9c RBP: 00007ffeed106a28 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 0000564cae660160 R14: 0000000000000001 R15: 0000000000000000 </TASK> ================================ WARNING: inconsistent lock state 5.17.0-syzkaller-13430-g787af64d05cd #0 Tainted: G W -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. udevd/3123 [HC0[0]:SC1[1]:HE0:SE0] takes: ffff8880140d2160 (&xa->xa_lock#8){+.?.}-{2:2}, at: xa_destroy+0xb3/0x360 lib/xarray.c:2207 {SOFTIRQ-ON-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:349 [inline] xa_insert include/linux/xarray.h:772 [inline] blk_mq_init_hctx block/blk-mq.c:3501 [inline] blk_mq_alloc_and_init_hctx+0x52d/0x1190 block/blk-mq.c:3962 blk_mq_realloc_hw_ctxs+0x43d/0x590 block/blk-mq.c:3991 blk_mq_init_allocated_queue+0x457/0x13d0 block/blk-mq.c:4053 blk_mq_init_queue_data block/blk-mq.c:3906 [inline] __blk_mq_alloc_disk+0xd1/0x1c0 block/blk-mq.c:3926 floppy_alloc_disk+0x3d/0x390 drivers/block/floppy.c:4495 do_floppy_init drivers/block/floppy.c:4576 [inline] floppy_async_init+0x316/0x21ca drivers/block/floppy.c:4746 async_run_entry_fn+0x9d/0x550 kernel/async.c:127 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 softirqs last enabled at (20583496): [<ffffffff8146ca53>] invoke_softirq kernel/softirq.c:432 [inline] softirqs last enabled at (20583496): [<ffffffff8146ca53>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 softirqs last disabled at (20587107): [<ffffffff8146ca53>] invoke_softirq kernel/softirq.c:432 [inline] softirqs last disabled at (20587107): [<ffffffff8146ca53>] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&xa->xa_lock#8); <Interrupt> *** DEADLOCK *** #0: ffffffff8c592858 (tomoyo_ss){....}-{0:0}, at: tomoyo_check_open_permission+0xe8/0x380 security/tomoyo/file.c:761 #2: ffffffff8bd7f3e0 (rcu_read_lock){....}-{1:2}, at: need_seqretry include/linux/seqlock.h:1158 [inline] #2: ffffffff8bd7f3e0 (rcu_read_lock){....}-{1:2}, at: prepend_path+0x25f/0xea0 fs/d_path.c:182 stack backtrace: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:3935 [inline] valid_state kernel/locking/lockdep.c:3947 [inline] mark_lock_irq kernel/locking/lockdep.c:4150 [inline] mark_lock.part.0.cold+0x18/0xd8 kernel/locking/lockdep.c:4607 mark_lock kernel/locking/lockdep.c:4571 [inline] mark_usage kernel/locking/lockdep.c:4502 [inline] __lock_acquire+0x11e7/0x56c0 kernel/locking/lockdep.c:4983 lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 blk_mq_release+0x2b1/0x3e0 block/blk-mq.c:3887 blk_release_queue+0x15b/0x320 block/blk-sysfs.c:780 blkg_free.part.0+0x112/0x1f0 block/blk-cgroup.c:86 blkg_free block/blk-cgroup.c:78 [inline] __blkg_release+0x105/0x160 block/blk-cgroup.c:102 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0x7b1/0x1880 kernel/rcu/tree.c:2786 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: 48 89 ef 5d e9 f1 90 4a 00 5d be 03 00 00 00 e9 36 66 74 02 66 0f 1f 44 00 00 48 8b be a8 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 <65> 8b 05 c9 a2 8a 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc900030ff5c8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000000 RDX: ffff888021002280 RSI: ffffffff81df460e RDI: 0000000000000003 RBP: ffffc900030ff6d8 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff81df4604 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88801ab435d0 R14: dffffc0000000000 R15: dffffc0000000000 __seqprop_spinlock_sequence include/linux/seqlock.h:277 [inline] read_seqbegin include/linux/seqlock.h:840 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1144 [inline] prepend_path+0x3b4/0xea0 fs/d_path.c:170 d_absolute_path+0xef/0x1a0 fs/d_path.c:233 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x272/0x380 security/tomoyo/file.c:771 tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline] tomoyo_file_open+0x9d/0xc0 security/tomoyo/tomoyo.c:306 do_dentry_open+0x349/0x11e0 fs/open.c:811 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 RIP: 0033:0x7fa17d125697 RSP: 002b:00007ffeed1068f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 BUG: sleeping function called from invalid context at kernel/locking/mutex.c:577 INFO: lockdep is turned off. Preemption disabled at: [<ffffffff89a000e1>] softirq_handle_begin kernel/softirq.c:396 [inline] [<ffffffff89a000e1>] __do_softirq+0xe1/0x9c2 kernel/softirq.c:534 CPU: 0 PID: 3123 Comm: udevd Tainted: G W 5.17.0-syzkaller-13430-g787af64d05cd #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 __might_resched.cold+0x222/0x26b kernel/sched/core.c:9733 blk_trace_shutdown+0x1d/0x100 kernel/trace/blktrace.c:773 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:753 blkg_free.part.0+0x112/0x1f0 block/blk-cgroup.c:86 blkg_free block/blk-cgroup.c:78 [inline] __blkg_release+0x105/0x160 block/blk-cgroup.c:102 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0x7b1/0x1880 kernel/rcu/tree.c:2786 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: 48 89 ef 5d e9 f1 90 4a 00 5d be 03 00 00 00 e9 36 66 74 02 66 0f 1f 44 00 00 48 8b be a8 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 <65> 8b 05 c9 a2 8a 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc900030ff5c8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000000 RDX: ffff888021002280 RSI: ffffffff81df460e RDI: 0000000000000003 RBP: ffffc900030ff6d8 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff81df4604 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88801ab435d0 R14: dffffc0000000000 R15: dffffc0000000000 __seqprop_spinlock_sequence include/linux/seqlock.h:277 [inline] read_seqbegin include/linux/seqlock.h:840 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1144 [inline] prepend_path+0x3b4/0xea0 fs/d_path.c:170 d_absolute_path+0xef/0x1a0 fs/d_path.c:233 tomoyo_get_absolute_path security/tomoyo/realpath.c:101 [inline] tomoyo_realpath_from_path+0x288/0x620 security/tomoyo/realpath.c:276 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x272/0x380 security/tomoyo/file.c:771 tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline] tomoyo_file_open+0x9d/0xc0 security/tomoyo/tomoyo.c:306 security_file_open+0x45/0xb0 security/security.c:1651 do_dentry_open+0x349/0x11e0 fs/open.c:811 do_open fs/namei.c:3476 [inline] path_openat+0x1c71/0x2910 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4c0 fs/open.c:1213 do_sys_open fs/open.c:1229 [inline] __do_sys_openat fs/open.c:1245 [inline] __se_sys_openat fs/open.c:1240 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1240 RIP: 0033:0x7fa17d125697 RAX: ffffffffffffffda RBX: 0000564cae660160 RCX: 00007fa17d125697 R13: 0000564cae660160 R14: 0000000000000001 R15: 0000000000000000 </TASK> BUG: sleeping function called from invalid context at block/blk-sysfs.c:766 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/0 preempt_count: 101, expected: 0 RCU nest depth: 0, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [<ffffffff895f3be9>] schedule_preempt_disabled+0x19/0x20 kernel/sched/core.c:6514 CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 5.17.0-syzkaller-13430-g787af64d05cd #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 __might_resched.cold+0x222/0x26b kernel/sched/core.c:9733 blk_release_queue+0x1f/0x320 block/blk-sysfs.c:766 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:753 blkg_free.part.0+0x112/0x1f0 block/blk-cgroup.c:86 blkg_free block/blk-cgroup.c:78 [inline] __blkg_release+0x105/0x160 block/blk-cgroup.c:102 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0x7b1/0x1880 kernel/rcu/tree.c:2786 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:734 Code: ff ff ff 48 89 df e8 d4 78 62 f8 e9 55 ff ff ff 4c 89 e7 e8 c7 78 62 f8 eb 96 0f 1f 44 00 00 eb 07 0f 00 2d d7 24 66 00 fb f4 <c3> cc cc cc cc 41 55 41 54 55 48 89 fd 53 e8 12 68 17 f8 e8 6d 1d RSP: 0018:ffffffff8ba07e40 EFLAGS: 00000246 RAX: 00000000000ff8da RBX: ffffffff8babc700 RCX: ffffffff895d77c1 RDX: ffffed1005947603 RSI: 0000000000000001 RDI: ffffffff8960688f RBP: 0000000000000000 R08: 0000000000000000 R09: ffff88802ca3b013 R10: ffffed1005947602 R11: 0000000000000000 R12: fffffbfff17578e0 R13: 0000000000000000 R14: ffffffff8db63990 R15: 0000000000000000 default_idle_call+0x87/0xd0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x401/0x590 kernel/sched/idle.c:303 secondary_startup_64_no_verify+0xc3/0xcb ---------------- Code disassembly (best guess): 0: 48 89 ef mov %rbp,%rdi 3: 5d pop %rbp 4: e9 f1 90 4a 00 jmpq 0x4a90fa 9: 5d pop %rbp a: be 03 00 00 00 mov $0x3,%esi f: e9 36 66 74 02 jmpq 0x274664a 14: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 1a: 48 8b be a8 01 00 00 mov 0x1a8(%rsi),%rdi 21: e8 b4 ff ff ff callq 0xffffffda 26: 31 c0 xor %eax,%eax 28: c3 retq 29: 90 nop * 2a: 65 8b 05 c9 a2 8a 7e mov %gs:0x7e8aa2c9(%rip),%eax # 0x7e8aa2fa <-- trapping instruction 31: 89 c1 mov %eax,%ecx 33: 48 8b 34 24 mov (%rsp),%rsi 37: 81 e1 00 01 00 00 and $0x100,%ecx 3d: 65 gs 3e: 48 rex.W 3f: 8b .byte 0x8b --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
