================================================================== 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 ffff8880a65d28c8 by task syz-executor.1/13160 CPU: 1 PID: 13160 Comm: syz-executor.1 Not tainted 5.1.0-rc2+ #69 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:132 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:227 [inline] rcu_do_batch kernel/rcu/tree.c:2475 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2788 [inline] rcu_core+0x928/0x1390 kernel/rcu/tree.c:2769 __do_softirq+0x266/0x95a kernel/softirq.c:293 invoke_softirq kernel/softirq.c:374 [inline] irq_exit+0x180/0x1d0 kernel/softirq.c:414 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:mod_zone_state mm/vmstat.c:482 [inline] RIP: 0010:dec_zone_page_state+0x94/0x1a0 mm/vmstat.c:532 Code: 69 5e 89 83 e3 03 48 69 c3 80 06 00 00 49 89 dc 49 8d 7c 05 58 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 d9 00 00 00 49 69 c4 80 06 00 00 41 89 f6 49 8b 7c 05 58 4a RSP: 0018:ffff888065bbf800 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff81328f70 RDX: 1ffff11025fff8db RSI: 0000000000000008 RDI: ffff88812fffc6d8 RBP: ffff888065bbf830 R08: ffff888060fb6640 R09: ffffed1015d25bc8 R10: ffffed1015d25bc7 R11: ffff8880ae92de3b R12: 0000000000000001 R13: ffff88812fffc000 R14: 00000000f0000000 R15: ffff888065bbf9c8 pgtable_page_dtor include/linux/mm.h:1949 [inline] ___pte_free_tlb+0x91/0x160 arch/x86/mm/pgtable.c:64 __pte_free_tlb arch/x86/include/asm/pgalloc.h:73 [inline] free_pte_range mm/memory.c:199 [inline] free_pmd_range mm/memory.c:217 [inline] free_pud_range mm/memory.c:251 [inline] free_p4d_range mm/memory.c:285 [inline] free_pgd_range+0x8e2/0xed0 mm/memory.c:365 free_pgtables+0x236/0x2f0 mm/memory.c:397 exit_mmap+0x2d1/0x530 mm/mmap.c:3139 __mmput kernel/fork.c:1046 [inline] mmput+0x15f/0x4c0 kernel/fork.c:1067 exit_mm kernel/exit.c:546 [inline] do_exit+0x816/0x2fa0 kernel/exit.c:863 do_group_exit+0x135/0x370 kernel/exit.c:980 get_signal+0x399/0x1d50 kernel/signal.c:2577 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458209 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8af85b2cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000073bfa8 RCX: 0000000000458209 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000073bfa8 RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000073bfac R13: 00007ffde2c1f9ef R14: 00007f8af85b39c0 R15: 000000000073bfac Allocated by task 13159: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:511 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3621 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:534 [inline] __do_sys_bpf+0x946/0x3e50 kernel/bpf/syscall.c:2695 __se_sys_bpf kernel/bpf/syscall.c:2672 [inline] __x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:2672 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8179: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3821 dev_map_free+0x43c/0x540 kernel/bpf/devmap.c:192 bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:298 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8880a65d27c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 264 bytes inside of 512-byte region [ffff8880a65d27c0, ffff8880a65d29c0) The buggy address belongs to the page: page:ffffea0002997480 count:1 mapcount:0 mapping:ffff88812c3f0940 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea000224bc08 ffffea00026be7c8 ffff88812c3f0940 raw: 0000000000000000 ffff8880a65d2040 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a65d2780: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8880a65d2800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a65d2880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a65d2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a65d2980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================