audit: type=1400 audit(1687774259.971:19): avc: denied { block_suspend } for pid=8571 comm="syz-executor.1" capability=36 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 syz-executor.7 (8570) used greatest stack depth: 23040 bytes left ======================================================== WARNING: possible irq lock inversion dependency detected 6.4.0-rc7-next-20230623 #1 Not tainted -------------------------------------------------------- syz-executor.2/4456 just changed the state of lock: ffffffff85815818 (blkg_stat_lock){+.-.}-{2:2}, at: __blkcg_rstat_flush.isra.0+0x11f/0x4e0 but this lock was taken by another, HARDIRQ-safe lock in the past: (per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)){-.-.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(blkg_stat_lock); local_irq_disable(); lock(per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)); lock(blkg_stat_lock); lock(per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)); *** DEADLOCK *** 5 locks held by syz-executor.2/4456: #0: ffffffff85687bb0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap+0xf5/0x1770 #1: ffff88801dba4260 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap+0x113/0x1770 #2: ffff8880190fde20 (&mm->mmap_lock/1){+.+.}-{3:3}, at: dup_mmap+0x163/0x1770 #3: ffffffff8560b5a0 (rcu_callback){....}-{0:0}, at: rcu_core+0x83e/0x28b0 #4: ffffffff8560b6c0 (rcu_read_lock){....}-{1:2}, at: __blkcg_rstat_flush.isra.0+0x93/0x4e0 the shortest dependencies between 2nd lock and 1st lock: -> (per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock_irqsave+0x3a/0x60 cgroup_rstat_updated+0xcb/0x2e0 __cgroup_account_cputime_field+0xa0/0x120 account_system_index_time+0x199/0x2c0 update_process_times+0x26/0x150 tick_sched_handle+0x8e/0x170 tick_sched_timer+0xe6/0x110 __hrtimer_run_queues+0x17f/0xb60 hrtimer_interrupt+0x2ef/0x750 __sysvec_apic_timer_interrupt+0xff/0x380 sysvec_apic_timer_interrupt+0x69/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 _raw_spin_unlock_irq+0x2b/0x40 css_task_iter_next+0x1f6/0x2e0 kernfs_seq_next+0x159/0x420 seq_read_iter+0xadd/0x1300 kernfs_fop_read_iter+0x4d4/0x690 vfs_read+0x4b5/0x8f0 ksys_read+0x122/0x250 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 IN-SOFTIRQ-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock_irqsave+0x3a/0x60 cgroup_rstat_updated+0xcb/0x2e0 __cgroup_account_cputime+0x75/0xc0 update_curr+0x350/0x6d0 dequeue_task_fair+0x20e/0x14a0 load_balance+0xcb4/0x2790 rebalance_domains+0x66c/0xc00 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 default_idle+0xf/0x20 default_idle_call+0x67/0xa0 do_idle+0x305/0x3c0 cpu_startup_entry+0x18/0x20 start_secondary+0x1ba/0x210 secondary_startup_64_no_verify+0x179/0x17b INITIAL USE at: lock_acquire+0x19a/0x4c0 _raw_spin_lock_irqsave+0x3a/0x60 cgroup_rstat_flush_locked+0x131/0xd80 cgroup_rstat_flush+0x37/0x50 do_flush_stats+0x97/0xf0 flush_memcg_stats_dwork+0x9/0x50 process_one_work+0xabf/0x1770 worker_thread+0x64f/0x12a0 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 } ... key at: [] __key.0+0x0/0x40 ... acquired at: _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 blkcg_rstat_flush+0x87/0xb0 cgroup_rstat_flush_locked+0x706/0xd80 cgroup_rstat_flush+0x37/0x50 do_flush_stats+0x97/0xf0 mem_cgroup_wb_stats+0x3d8/0x4b0 balance_dirty_pages+0x339/0x2640 balance_dirty_pages_ratelimited_flags+0xbce/0x1130 fault_dirty_shared_page+0x2b3/0x500 do_wp_page+0x3c8/0x3b00 __handle_mm_fault+0xcbc/0x2d20 handle_mm_fault+0x1af/0xba0 do_user_addr_fault+0x58e/0x12f0 exc_page_fault+0x9c/0x1a0 asm_exc_page_fault+0x26/0x30 -> (blkg_stat_lock){+.-.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 __orc_find+0x6f/0xf0 unwind_next_frame+0x2b1/0x2490 arch_stack_walk+0x87/0xf0 stack_trace_save+0x90/0xd0 kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc+0x16b/0x370 __create_object+0x3c/0xc90 kmem_cache_alloc+0x20b/0x370 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'. vm_area_dup+0x52/0x160 dup_mmap+0x94e/0x1770 copy_process+0x3e68/0x7320 kernel_clone+0xeb/0x7d0 __do_sys_clone+0xba/0x100 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 IN-SOFTIRQ-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 __orc_find+0x6f/0xf0 unwind_next_frame+0x2b1/0x2490 arch_stack_walk+0x87/0xf0 stack_trace_save+0x90/0xd0 kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc+0x16b/0x370 __create_object+0x3c/0xc90 kmem_cache_alloc+0x20b/0x370 vm_area_dup+0x52/0x160 dup_mmap+0x94e/0x1770 copy_process+0x3e68/0x7320 kernel_clone+0xeb/0x7d0 __do_sys_clone+0xba/0x100 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 INITIAL USE at: lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 blkcg_rstat_flush+0x87/0xb0 cgroup_rstat_flush_locked+0x706/0xd80 cgroup_rstat_flush+0x37/0x50 do_flush_stats+0x97/0xf0 mem_cgroup_wb_stats+0x3d8/0x4b0 balance_dirty_pages+0x339/0x2640 balance_dirty_pages_ratelimited_flags+0xbce/0x1130 fault_dirty_shared_page+0x2b3/0x500 do_wp_page+0x3c8/0x3b00 __handle_mm_fault+0xcbc/0x2d20 handle_mm_fault+0x1af/0xba0 do_user_addr_fault+0x58e/0x12f0 exc_page_fault+0x9c/0x1a0 asm_exc_page_fault+0x26/0x30 } ... key at: [] blkg_stat_lock+0x18/0x60 ... acquired at: __lock_acquire+0x8b8/0x6340 lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 __orc_find+0x6f/0xf0 unwind_next_frame+0x2b1/0x2490 arch_stack_walk+0x87/0xf0 stack_trace_save+0x90/0xd0 kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc+0x16b/0x370 __create_object+0x3c/0xc90 kmem_cache_alloc+0x20b/0x370 vm_area_dup+0x52/0x160 dup_mmap+0x94e/0x1770 copy_process+0x3e68/0x7320 kernel_clone+0xeb/0x7d0 __do_sys_clone+0xba/0x100 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 stack backtrace: CPU: 1 PID: 4456 Comm: syz-executor.2 Not tainted 6.4.0-rc7-next-20230623 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x91/0xf0 print_irq_inversion_bug.part.0+0x3d5/0x570 mark_lock.part.0+0x900/0x2f50 __lock_acquire+0x8b8/0x6340 lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0010:__orc_find+0x6f/0xf0 Code: 72 4d 4c 89 e0 48 29 e8 48 89 c2 48 c1 e8 3f 48 c1 fa 02 48 01 d0 48 d1 f8 48 8d 5c 85 00 48 89 d8 48 c1 e8 03 42 0f b6 14 38 <48> 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 50 48 63 03 48 01 RSP: 0018:ffff888013107430 EFLAGS: 00000216 RAX: 1ffffffff0bb3528 RBX: ffffffff85d9a940 RCX: ffffffff81171c5a RDX: 0000000000000000 RSI: ffffffff860a6160 RDI: ffffffff85d9a940 RBP: ffffffff85d9a940 R08: ffffffff860a6160 R09: ffff888013107528 R10: 0000000000038001 R11: 0000000000007260 R12: ffffffff85d9a940 R13: ffffffff85d9a940 R14: ffffffff85d9a940 R15: dffffc0000000000 unwind_next_frame+0x2b1/0x2490 arch_stack_walk+0x87/0xf0 stack_trace_save+0x90/0xd0 kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc+0x16b/0x370 __create_object+0x3c/0xc90 kmem_cache_alloc+0x20b/0x370 vm_area_dup+0x52/0x160 dup_mmap+0x94e/0x1770 copy_process+0x3e68/0x7320 kernel_clone+0xeb/0x7d0 __do_sys_clone+0xba/0x100 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 RIP: 0033:0x7f190940b10b Code: ed 0f 85 60 01 00 00 64 4c 8b 0c 25 10 00 00 00 45 31 c0 4d 8d 91 d0 02 00 00 31 d2 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 89 00 00 00 41 89 c5 85 c0 0f 85 90 00 00 RSP: 002b:00007ffd7a4c0220 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f190940b10b RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 00005555573b5400 R10: 00005555573b56d0 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffd7a4c0300 audit: type=1400 audit(1687774260.283:20): avc: denied { create } for pid=8571 comm="syz-executor.1" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:unconfined_execmem_exec_t:s0 tclass=udp_socket permissive=1 ---------------- Code disassembly (best guess): 0: 72 4d jb 0x4f 2: 4c 89 e0 mov %r12,%rax 5: 48 29 e8 sub %rbp,%rax 8: 48 89 c2 mov %rax,%rdx b: 48 c1 e8 3f shr $0x3f,%rax f: 48 c1 fa 02 sar $0x2,%rdx 13: 48 01 d0 add %rdx,%rax 16: 48 d1 f8 sar %rax 19: 48 8d 5c 85 00 lea 0x0(%rbp,%rax,4),%rbx 1e: 48 89 d8 mov %rbx,%rax 21: 48 c1 e8 03 shr $0x3,%rax 25: 42 0f b6 14 38 movzbl (%rax,%r15,1),%edx * 2a: 48 89 d8 mov %rbx,%rax <-- trapping instruction 2d: 83 e0 07 and $0x7,%eax 30: 83 c0 03 add $0x3,%eax 33: 38 d0 cmp %dl,%al 35: 7c 04 jl 0x3b 37: 84 d2 test %dl,%dl 39: 75 50 jne 0x8b 3b: 48 63 03 movslq (%rbx),%rax 3e: 48 rex.W 3f: 01 .byte 0x1