================================================================== 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 ffff88806fb3c6c8 by task syz-executor.5/20033 CPU: 1 PID: 20033 Comm: syz-executor.5 Not tainted 5.0.0-rc4+ #34 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+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 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:766 [inline] RIP: 0010:lock_acquire+0x1ea/0x3f0 kernel/locking/lockdep.c:3844 Code: 7c 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 c7 01 00 00 48 83 3d 62 30 3b 07 00 0f 84 3b 01 00 00 48 8b 7d c8 57 9d <0f> 1f 44 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 65 8b RSP: 0000:ffff8880a84bfb00 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff112503e RBX: ffff8880596b8100 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffff8880596b89a8 RDI: 0000000000000282 RBP: ffff8880a84bfb48 R08: 0000000000000001 R09: 0000000000006c30 R10: ffff8880596b89a8 R11: 0000000000000001 R12: ffffffff88a133e0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 __fs_reclaim_acquire mm/page_alloc.c:3883 [inline] fs_reclaim_acquire.part.0+0x24/0x30 mm/page_alloc.c:3894 fs_reclaim_acquire mm/page_alloc.c:4474 [inline] prepare_alloc_pages mm/page_alloc.c:4471 [inline] __alloc_pages_nodemask+0x46f/0x710 mm/page_alloc.c:4523 alloc_pages_current+0x107/0x210 mm/mempolicy.c:2106 alloc_pages include/linux/gfp.h:509 [inline] pte_alloc_one+0x1b/0x1a0 arch/x86/mm/pgtable.c:35 do_fault_around mm/memory.c:3385 [inline] do_read_fault mm/memory.c:3425 [inline] do_fault mm/memory.c:3556 [inline] handle_pte_fault mm/memory.c:3787 [inline] __handle_mm_fault+0x34e4/0x3f20 mm/memory.c:3911 handle_mm_fault+0x43f/0xb30 mm/memory.c:3948 do_user_addr_fault arch/x86/mm/fault.c:1475 [inline] __do_page_fault+0x5da/0xd60 arch/x86/mm/fault.c:1541 do_page_fault+0x71/0x581 arch/x86/mm/fault.c:1572 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1143 RIP: 0033:0x4563fa Code: Bad RIP value. RSP: 002b:00007ffe366f1aa0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00007ffe366f1aa0 RCX: 00000000004563fa RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007ffe366f1ae0 R08: 0000000000000001 R09: 0000000002566940 R10: 0000000002566c10 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005 Allocated by task 20019: 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 12: 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 ffff88806fb3c5c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 264 bytes inside of 512-byte region [ffff88806fb3c5c0, ffff88806fb3c7c0) The buggy address belongs to the page: page:ffffea0001becf00 count:1 mapcount:0 mapping:ffff88812c3f0940 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00026eab48 ffffea0001becf48 ffff88812c3f0940 raw: 0000000000000000 ffff88806fb3c0c0 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806fb3c580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff88806fb3c600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806fb3c680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806fb3c700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806fb3c780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================