================================================================== 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 ffff88808e99d8c8 by task syz-fuzzer/7484 CPU: 1 PID: 7484 Comm: syz-fuzzer Not tainted 5.0.0-rc4+ #35 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 kobject: 'queues' (00000000eb41e098): kobject_uevent_env 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: 0033:0x72f9f7 Code: c7 44 24 10 00 00 00 00 48 c7 44 24 18 00 00 00 00 e9 7d 70 fe ff cc cc cc cc cc cc cc cc cc cc cc cc cc 48 8b 44 24 08 84 00 <48> 89 44 24 08 48 c7 44 24 10 00 00 00 00 48 c7 44 24 18 00 00 00 kobject: 'queues' (00000000eb41e098): kobject_uevent_env: filter function caused the event to drop! RSP: 002b:000000c428597298 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 000000c42981e600 RBX: 000000000072f9f0 RCX: 000000c428597860 RDX: 0000000000ba84e0 RSI: 000000c42981e600 RDI: 0000000000000348 RBP: 000000c428597320 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000991aea R11: 0000000000000004 R12: 0000000000000000 R13: 0000000000000020 R14: 0000000000000013 R15: 000000c427baed30 Allocated by task 23257: 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 kobject: 'rx-0' (00000000afb64b65): kobject_add_internal: parent: 'queues', set: 'queues' 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 kobject: 'rx-0' (00000000afb64b65): kobject_uevent_env 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 kobject: 'rx-0' (00000000afb64b65): fill_kobj_path: path = '/devices/virtual/net/4/queues/rx-0' 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 ffff88808e99d7c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 264 bytes inside of 512-byte region [ffff88808e99d7c0, ffff88808e99d9c0) The buggy address belongs to the page: page:ffffea00023a6740 count:1 mapcount:0 mapping:ffff88812c3f0940 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002411cc8 ffffea00023b5148 ffff88812c3f0940 kobject: 'tx-0' (0000000019c6309e): kobject_add_internal: parent: 'queues', set: 'queues' raw: 0000000000000000 ffff88808e99d040 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808e99d780: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff88808e99d800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88808e99d880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808e99d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808e99d980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================