================================================================== BUG: KASAN: use-after-free in nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 Read of size 1 at addr ffff8801ae7e595d by task syz-executor5/16210 CPU: 1 PID: 16210 Comm: syz-executor5 Not tainted 4.17.0-rc6+ #74 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+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 nfnl_acct_new+0x574/0xc50 net/netfilter/nfnetlink_acct.c:118 nfnetlink_rcv_msg+0xd6d/0x1050 net/netfilter/nfnetlink.c:228 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2448 nfnetlink_rcv+0x1b8/0x4b0 net/netfilter/nfnetlink.c:551 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x58b/0x740 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x9f0/0xfa0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 sock_write_iter+0x35a/0x5a0 net/socket.c:908 call_write_iter include/linux/fs.h:1784 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x64d/0x960 fs/read_write.c:487 vfs_write+0x1f8/0x560 fs/read_write.c:549 ksys_write+0xf9/0x250 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a09 RSP: 002b:00007f8fec40ac68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8fec40b6d4 RCX: 0000000000455a09 RDX: 000000000000001f RSI: 0000000020000000 RDI: 0000000000000015 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000007a8 R14: 0000000000700860 R15: 0000000000000000 Allocated by task 519: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3696 __kmalloc_reserve.isra.39+0x3a/0xe0 net/core/skbuff.c:137 __alloc_skb+0x14d/0x780 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:989 [inline] nlmsg_new include/net/netlink.h:511 [inline] __neigh_notify+0x8c/0x160 net/core/neighbour.c:2907 neigh_cleanup_and_release+0x7b/0xe0 net/core/neighbour.c:104 neigh_flush_dev+0x5b1/0x8e0 net/core/neighbour.c:278 neigh_ifdown+0x44/0x2c0 net/core/neighbour.c:294 rt6_disable_ip+0x6a1/0x7c0 net/ipv6/route.c:4072 addrconf_ifdown+0x167/0x1650 net/ipv6/addrconf.c:3647 addrconf_notify+0x6e9/0x27e0 net/ipv6/addrconf.c:3572 notifier_call_chain+0x178/0x380 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735 call_netdevice_notifiers net/core/dev.c:1753 [inline] dev_close_many+0x43c/0x8a0 net/core/dev.c:1505 rollback_registered_many+0x523/0xed0 net/core/dev.c:7467 unregister_netdevice_many+0xf3/0x4c0 net/core/dev.c:8595 ip6gre_exit_batch_net+0x5c3/0x7d0 net/ipv6/ip6_gre.c:1609 ops_exit_list.isra.7+0x105/0x160 net/core/net_namespace.c:155 cleanup_net+0x51d/0xb20 net/core/net_namespace.c:523 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Freed by task 519: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 skb_free_head+0x99/0xc0 net/core/skbuff.c:550 skb_release_data+0x690/0x860 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] consume_skb+0x18b/0x550 net/core/skbuff.c:701 netlink_broadcast_filtered+0x666/0x1580 net/netlink/af_netlink.c:1512 netlink_broadcast net/netlink/af_netlink.c:1534 [inline] nlmsg_multicast include/net/netlink.h:591 [inline] nlmsg_notify+0xa0/0x1a0 net/netlink/af_netlink.c:2491 rtnl_notify+0xce/0xf0 net/core/rtnetlink.c:732 __neigh_notify+0xe2/0x160 net/core/neighbour.c:2918 neigh_cleanup_and_release+0x7b/0xe0 net/core/neighbour.c:104 neigh_flush_dev+0x5b1/0x8e0 net/core/neighbour.c:278 neigh_ifdown+0x44/0x2c0 net/core/neighbour.c:294 rt6_disable_ip+0x6a1/0x7c0 net/ipv6/route.c:4072 addrconf_ifdown+0x167/0x1650 net/ipv6/addrconf.c:3647 addrconf_notify+0x6e9/0x27e0 net/ipv6/addrconf.c:3572 notifier_call_chain+0x178/0x380 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735 call_netdevice_notifiers net/core/dev.c:1753 [inline] dev_close_many+0x43c/0x8a0 net/core/dev.c:1505 rollback_registered_many+0x523/0xed0 net/core/dev.c:7467 unregister_netdevice_many+0xf3/0x4c0 net/core/dev.c:8595 ip6gre_exit_batch_net+0x5c3/0x7d0 net/ipv6/ip6_gre.c:1609 ops_exit_list.isra.7+0x105/0x160 net/core/net_namespace.c:155 cleanup_net+0x51d/0xb20 net/core/net_namespace.c:523 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 The buggy address belongs to the object at ffff8801ae7e57c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 413 bytes inside of 512-byte region [ffff8801ae7e57c0, ffff8801ae7e59c0) The buggy address belongs to the page: page:ffffea0006b9f940 count:1 mapcount:0 mapping:ffff8801ae7e5040 index:0xffff8801ae7e57c0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801ae7e5040 ffff8801ae7e57c0 0000000100000005 raw: ffffea0006c642a0 ffffea00071b2ca0 ffff8801da800940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801ae7e5800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801ae7e5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801ae7e5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801ae7e5980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8801ae7e5a00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================