================================================================== BUG: KASAN: slab-out-of-bounds in __xfrm6_tunnel_spi_lookup+0x3a9/0x3b0 net/ipv6/xfrm6_tunnel.c:79 Read of size 8 at addr ffff8880933d6e28 by task syz-executor.5/16458 CPU: 0 PID: 16458 Comm: syz-executor.5 Not tainted 5.8.0-rc5-next-20200716-syzkaller #0 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+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 __xfrm6_tunnel_spi_lookup+0x3a9/0x3b0 net/ipv6/xfrm6_tunnel.c:79 xfrm6_tunnel_spi_lookup+0x8a/0x1d0 net/ipv6/xfrm6_tunnel.c:95 xfrmi6_rcv_tunnel+0xb9/0x100 net/xfrm/xfrm_interface.c:824 tunnel46_rcv+0xef/0x2b0 net/ipv6/tunnel6.c:193 ip6_protocol_deliver_rcu+0x2e8/0x1670 net/ipv6/ip6_input.c:433 ip6_input_finish+0x7f/0x160 net/ipv6/ip6_input.c:474 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:483 dst_input include/net/dst.h:449 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ipv6_rcv+0x28e/0x3c0 net/ipv6/ip6_input.c:307 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5287 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5401 netif_receive_skb_internal net/core/dev.c:5503 [inline] netif_receive_skb+0x159/0x990 net/core/dev.c:5562 tun_rx_batched.isra.0+0x460/0x720 drivers/net/tun.c:1518 tun_get_user+0x23b2/0x35b0 drivers/net/tun.c:1972 tun_chr_write_iter+0xba/0x151 drivers/net/tun.c:2001 call_write_iter include/linux/fs.h:1879 [inline] new_sync_write+0x422/0x650 fs/read_write.c:515 vfs_write+0x5c6/0x6f0 fs/read_write.c:595 ksys_write+0x12d/0x250 fs/read_write.c:648 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x415c91 Code: Bad RIP value. RSP: 002b:00007ff6dc4e8c60 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000078bf00 RCX: 0000000000415c91 RDX: 000000000000004a RSI: 0000000020000280 RDI: 00000000000000f0 RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ff6dc4e99d0 R11: 0000000000000293 R12: 000000000078bf0c R13: 00007ffde5100ccf R14: 00007ff6dc4e99c0 R15: 000000000078bf0c Allocated by task 3903: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 kmem_cache_alloc_trace+0x16e/0x2c0 mm/slab.c:3550 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:666 [inline] kernfs_fop_open+0x2c5/0xd40 fs/kernfs/file.c:647 do_dentry_open+0x4b9/0x11b0 fs/open.c:822 do_open fs/namei.c:3249 [inline] path_openat+0x1b97/0x2720 fs/namei.c:3366 do_filp_open+0x17e/0x3c0 fs/namei.c:3393 do_sys_openat2+0x16d/0x3e0 fs/open.c:1173 do_sys_open fs/open.c:1189 [inline] ksys_open include/linux/syscalls.h:1398 [inline] __do_sys_open fs/open.c:1195 [inline] __se_sys_open fs/open.c:1193 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1193 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 3903: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3418 [inline] kfree+0x103/0x2c0 mm/slab.c:3756 kernfs_fop_release+0x120/0x190 fs/kernfs/file.c:782 __fput+0x27e/0x8e0 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:135 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:239 [inline] __prepare_exit_to_usermode+0x1e0/0x1f0 arch/x86/entry/common.c:269 do_syscall_64+0x6c/0xe0 arch/x86/entry/common.c:393 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Last call_rcu(): kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346 __call_rcu kernel/rcu/tree.c:2883 [inline] call_rcu+0x14f/0x7e0 kernel/rcu/tree.c:2957 inetdev_destroy net/ipv4/devinet.c:328 [inline] inetdev_event+0xcc5/0x14fd net/ipv4/devinet.c:1599 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2033 call_netdevice_notifiers_extack net/core/dev.c:2045 [inline] call_netdevice_notifiers net/core/dev.c:2059 [inline] rollback_registered_many+0x665/0xf60 net/core/dev.c:8977 unregister_netdevice_many.part.0+0x1a/0x2f0 net/core/dev.c:10122 unregister_netdevice_many+0x36/0x50 net/core/dev.c:10121 ip_tunnel_delete_nets+0x3da/0x580 net/ipv4/ip_tunnel.c:1125 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189 cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the object at ffff8880933d6c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 40 bytes to the right of 512-byte region [ffff8880933d6c00, ffff8880933d6e00) The buggy address belongs to the page: page:00000000ae679002 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x933d6 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00029cad88 ffffea00024c55c8 ffff8880aa000600 raw: 0000000000000000 ffff8880933d6000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880933d6d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880933d6d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880933d6e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880933d6e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880933d6f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================