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BUG: KASAN: use-after-free in dev_map_flush_old kernel/bpf/devmap.c:389 [inline]
BUG: KASAN: use-after-free in __dev_map_entry_free+0x2a9/0x330 kernel/bpf/devmap.c:403
Read of size 8 at addr ffff888091ec5d88 by task kworker/1:4/7780

CPU: 1 PID: 7780 Comm: kworker/1:4 Not tainted 5.0.0-rc4+ #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue:            (null) (events)
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 dev_map_flush_old kernel/bpf/devmap.c:389 [inline]
 __dev_map_entry_free+0x2a9/0x330 kernel/bpf/devmap.c:403
 __rcu_reclaim kernel/rcu/rcu.h:240 [inline]
 rcu_do_batch kernel/rcu/tree.c:2452 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline]
 rcu_process_callbacks+0x928/0x1390 kernel/rcu/tree.c:2754
 __do_softirq+0x266/0x95a kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x180/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x14a/0x570 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x54/0x90 kernel/locking/spinlock.c:192
Code: c0 00 82 92 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 33 48 83 3d c5 64 8e 01 00 74 20 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 32 91 49 fa 65 8b 05 7b d0 fd 78 85 c0 74 06 41
RSP: 0018:ffff888088dafce8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff1125040 RBX: ffff888088da2580 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff888088da2dfc
RBP: ffff888088dafcf0 R08: ffff888088da2580 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880ae92cfc0
R13: ffff8880858ac1c0 R14: 0000000000000000 R15: 0000000000000000
 finish_lock_switch kernel/sched/core.c:2594 [inline]
 finish_task_switch+0x146/0x790 kernel/sched/core.c:2694
 context_switch kernel/sched/core.c:2847 [inline]
 __schedule+0x81f/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 worker_thread+0x248/0xe40 kernel/workqueue.c:2317
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Allocated by task 3634:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3609
 kmalloc include/linux/slab.h:545 [inline]
 kzalloc include/linux/slab.h:740 [inline]
 dev_map_alloc kernel/bpf/devmap.c:102 [inline]
 dev_map_alloc+0x1be/0x6e0 kernel/bpf/devmap.c:88
 find_and_alloc_map kernel/bpf/syscall.c:129 [inline]
 map_create kernel/bpf/syscall.c:526 [inline]
 __do_sys_bpf+0x97b/0x3ea0 kernel/bpf/syscall.c:2642
 __se_sys_bpf kernel/bpf/syscall.c:2619 [inline]
 __x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:2619
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 2980:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466
 __cache_free mm/slab.c:3487 [inline]
 kfree+0xcf/0x230 mm/slab.c:3806
 dev_map_free+0x43c/0x540 kernel/bpf/devmap.c:192
 bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:290
 process_one_work+0x98e/0x1760 kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff888091ec5c80
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 264 bytes inside of
 512-byte region [ffff888091ec5c80, ffff888091ec5e80)
The buggy address belongs to the page:
page:ffffea000247b140 count:1 mapcount:0 mapping:ffff88812c3f0940 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea000222e048 ffffea000222e108 ffff88812c3f0940
raw: 0000000000000000 ffff888091ec5000 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888091ec5c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888091ec5d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888091ec5d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888091ec5e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888091ec5e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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