================================================================== BUG: KASAN: use-after-free in inet_frag_destroy_rcu+0xd9/0xe0 net/ipv4/inet_fragment.c:201 Read of size 8 at addr ffff8880a472d318 by task kworker/u4:5/9546 CPU: 0 PID: 9546 Comm: kworker/u4:5 Not tainted 5.2.0-rc1+ #3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net 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:debug_lockdep_rcu_enabled.part.0+0x26/0x60 kernel/rcu/update.c:237 Code: 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 65 48 8b 1c 25 c0 fd 01 00 48 8d bb 7c 08 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 10 8b RSP: 0000:ffff88806399fb10 EFLAGS: 00000a03 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffff8880a9260240 RCX: 1ffffffff13016d6 RDX: 1ffff1101524c157 RSI: ffffffff88ba3180 RDI: ffff8880a9260abc RBP: ffff88806399fb18 R08: ffff8880a9260240 R09: 0000000000000004 R10: ffffed1015d06bdf R11: ffff8880ae835efb R12: ffffffff880ae5c0 R13: 000000000000010b R14: 00000000000022e3 R15: dffffc0000000000 debug_lockdep_rcu_enabled+0x71/0xa0 kernel/rcu/update.c:236 ___might_sleep+0x30/0x280 kernel/sched/core.c:6103 inet_twsk_purge+0x96/0x5f0 net/ipv4/inet_timewait_sock.c:267 tcp_sk_exit_batch+0x22/0xa0 net/ipv4/tcp_ipv4.c:2720 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:157 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:553 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 Allocated by task 8832: 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] ipv4_frags_init_net+0x48/0x4e0 net/ipv4/ip_fragment.c:645 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 10826: 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 ffff8880a472d300 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of 512-byte region [ffff8880a472d300, ffff8880a472d500) The buggy address belongs to the page: page:ffffea000291cb40 refcount:1 mapcount:0 mapping:ffff8880aa400940 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00028589c8 ffffea00022b3788 ffff8880aa400940 raw: 0000000000000000 ffff8880a472d080 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a472d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a472d280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a472d300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a472d380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a472d400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================