================================================================== BUG: KASAN: use-after-free in inet_frag_destroy_rcu+0xd9/0xe0 net/ipv4/inet_fragment.c:201 Read of size 8 at addr ffff8880956bd818 by task blkid/17416 CPU: 0 PID: 17416 Comm: blkid Not tainted 5.2.0-rc1+ #4 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:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 inet_frag_destroy_rcu+0xd9/0xe0 net/ipv4/inet_fragment.c:201 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2092 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline] rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291 __do_softirq+0x25c/0x94c 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+0x13b/0x550 arch/x86/kernel/apic/apic.c:1068 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806 RIP: 0010:arch_vma_access_permitted arch/x86/include/asm/mmu_context.h:336 [inline] RIP: 0010:handle_mm_fault+0x340/0xa90 mm/memory.c:4043 Code: 0f 8f 5b 05 00 00 e8 5f 85 d5 ff 44 89 eb 31 ff 81 e3 80 01 00 00 89 de e8 cd 86 d5 ff 85 db 0f 84 8a 01 00 00 49 8d 44 24 50 <48> 89 45 d0 e8 37 85 d5 ff 44 89 eb 31 ff 83 e3 40 89 de e8 a8 86 RSP: 0000:ffff888069467e50 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 RAX: ffff8880a9aacba8 RBX: 0000000000000100 RCX: ffffffff819b1f23 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000005 RBP: ffff888069467e90 R08: ffff88806a64c700 R09: 0000000000000002 R10: ffffed1015d06bdf R11: ffff8880ae835efb R12: ffff8880a9aacb58 R13: 0000000000000154 R14: 00007f4b9d6f07d0 R15: ffff8880a9aacb98 do_user_addr_fault arch/x86/mm/fault.c:1457 [inline] __do_page_fault+0x5ef/0xda0 arch/x86/mm/fault.c:1523 do_page_fault+0x71/0x57d arch/x86/mm/fault.c:1554 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1156 RIP: 0033:0x7f4b9d6f07d0 Code: Bad RIP value. RSP: 002b:00007ffcbf8e83e8 EFLAGS: 00010202 RAX: 00007f4b9d6f07d0 RBX: 00007f4b9de3f9a8 RCX: 0000000000000001 RDX: 00000000000000c0 RSI: 0000000000000025 RDI: 0000000000000002 RBP: 00007ffcbf8e84d0 R08: 0000000000000001 R09: 000000000000002f R10: 00007f4b9d68baf0 R11: 00007ffcbf8e8220 R12: 00007f4b9d66d000 R13: 00007f4b9d9f4038 R14: 00007f4b9d68bac0 R15: 00007f4b9d9f4d98 Allocated by task 8565: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503 kmem_cache_alloc_trace+0x151/0x750 mm/slab.c:3555 kmalloc include/linux/slab.h:547 [inline] kzalloc include/linux/slab.h:742 [inline] fqdir_init include/net/inet_frag.h:115 [inline] ipv6_frags_init_net+0x48/0x460 net/ipv6/reassembly.c:513 ops_init+0xb3/0x410 net/core/net_namespace.c:130 setup_net+0x2d3/0x740 net/core/net_namespace.c:316 copy_net_ns+0x1df/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:206 ksys_unshare+0x440/0x980 kernel/fork.c:2692 __do_sys_unshare kernel/fork.c:2760 [inline] __se_sys_unshare kernel/fork.c:2758 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2758 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 3757: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kfree+0xcf/0x220 mm/slab.c:3755 fqdir_rwork_fn+0x33/0x40 net/ipv4/inet_fragment.c:154 process_one_work+0x989/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8880956bd800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of 512-byte region [ffff8880956bd800, ffff8880956bda00) The buggy address belongs to the page: page:ffffea000255af40 refcount:1 mapcount:0 mapping:ffff8880aa400940 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00026cf608 ffffea0002a47248 ffff8880aa400940 raw: 0000000000000000 ffff8880956bd080 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880956bd700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880956bd780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880956bd800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880956bd880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880956bd900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================