IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready team0: Port device team_slave_1 added IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready ================================================================== BUG: KASAN: use-after-free in pppol2tp_session_close+0xcd/0xe0 net/l2tp/l2tp_ppp.c:436 Read of size 8 at addr ffff8880625e6960 by task kworker/u4:2/11228 CPU: 1 PID: 11228 Comm: kworker/u4:2 Not tainted 4.14.158-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: l2tp l2tp_tunnel_del_work Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x142/0x197 lib/dump_stack.c:58 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 pppol2tp_session_close+0xcd/0xe0 net/l2tp/l2tp_ppp.c:436 l2tp_tunnel_closeall+0x243/0x380 net/l2tp/l2tp_core.c:1340 l2tp_tunnel_del_work+0x64/0x410 net/l2tp/l2tp_core.c:1380 process_one_work+0x863/0x1600 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Allocated by task 25917: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529 __do_kmalloc mm/slab.c:3720 [inline] __kmalloc+0x15d/0x7a0 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] kzalloc include/linux/slab.h:661 [inline] __register_sysctl_table+0xc7/0xe50 fs/proc/proc_sysctl.c:1304 register_net_sysctl+0x29/0x30 net/sysctl_net.c:120 __addrconf_sysctl_register+0x209/0x3e0 net/ipv6/addrconf.c:6411 addrconf_sysctl_register net/ipv6/addrconf.c:6458 [inline] addrconf_sysctl_register+0xf9/0x1a0 net/ipv6/addrconf.c:6447 ipv6_add_dev net/ipv6/addrconf.c:460 [inline] ipv6_add_dev+0x8e2/0xfb0 net/ipv6/addrconf.c:375 addrconf_notify+0x60f/0x1b40 net/ipv6/addrconf.c:3365 notifier_call_chain+0x111/0x1b0 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x56/0x70 net/core/dev.c:1671 call_netdevice_notifiers net/core/dev.c:1687 [inline] register_netdevice+0x9c8/0xca0 net/core/dev.c:7697 veth_newlink+0x4c8/0x900 drivers/net/veth.c:443 rtnl_newlink+0xecb/0x1700 net/core/rtnetlink.c:2719 rtnetlink_rcv_msg+0x3da/0xb70 net/core/rtnetlink.c:4306 netlink_rcv_skb+0x14f/0x3c0 net/netlink/af_netlink.c:2432 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4318 netlink_unicast_kernel net/netlink/af_netlink.c:1286 [inline] netlink_unicast+0x44d/0x650 net/netlink/af_netlink.c:1312 netlink_sendmsg+0x7c4/0xc60 net/netlink/af_netlink.c:1877 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xce/0x110 net/socket.c:656 SYSC_sendto+0x206/0x310 net/socket.c:1763 SyS_sendto+0x40/0x50 net/socket.c:1731 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 17: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcc/0x270 mm/slab.c:3815 __rcu_reclaim kernel/rcu/rcu.h:190 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x8d0/0x12b0 kernel/rcu/tree.c:2946 __do_softirq+0x244/0x9a0 kernel/softirq.c:288 The buggy address belongs to the object at ffff8880625e6580 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 992 bytes inside of 2048-byte region [ffff8880625e6580, ffff8880625e6d80) The buggy address belongs to the page: page:ffffea0001897980 count:1 mapcount:0 mapping:ffff8880625e6580 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffff8880625e6580 0000000000000000 0000000100000003 raw: ffffea0001e8ed20 ffffea0001e1bca0 ffff8880aa800c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880625e6800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880625e6880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880625e6900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880625e6980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880625e6a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================