============================= WARNING: suspicious RCU usage 4.14.232-syzkaller #0 Not tainted ----------------------------- include/net/sock.h:1800 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 4 locks held by kworker/u4:7/17254: #0: ("%s""netns"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: (net_cleanup_work){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (net_mutex){+.+.}, at: [] cleanup_net+0x110/0x840 net/core/net_namespace.c:450 #3: (rtnl_mutex){+.+.}, at: [] netdev_run_todo+0x20e/0xad0 net/core/dev.c:7926 stack backtrace: CPU: 0 PID: 17254 Comm: kworker/u4:7 Not tainted 4.14.232-syzkaller #0 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:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 __sk_dst_set include/net/sock.h:1800 [inline] __sk_dst_reset include/net/sock.h:1820 [inline] tcp_disconnect+0x1412/0x1890 net/ipv4/tcp.c:2383 rds_tcp_conn_paths_destroy net/rds/tcp.c:515 [inline] rds_tcp_kill_sock net/rds/tcp.c:544 [inline] rds_tcp_dev_event+0x73f/0xa30 net/rds/tcp.c:573 notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93 call_netdevice_notifiers_info net/core/dev.c:1667 [inline] call_netdevice_notifiers net/core/dev.c:1683 [inline] netdev_run_todo+0x242/0xad0 net/core/dev.c:7927 default_device_exit_batch+0x2e2/0x380 net/core/dev.c:8747 ops_exit_list+0xf9/0x150 net/core/net_namespace.c:145 cleanup_net+0x3b3/0x840 net/core/net_namespace.c:484 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 FAT-fs (loop1): Unrecognized mount option "audit" or missing value FAT-fs (loop1): Unrecognized mount option "audit" or missing value tmpfs: Bad value 'd' for mount option 'mpol' tmpfs: Bad value 'd' for mount option 'mpol' FAT-fs (loop1): Unrecognized mount option "audit" or missing value ip_tables: iptables: counters copy to user failed while replacing table ip_tables: iptables: counters copy to user failed while replacing table ip_tables: iptables: counters copy to user failed while replacing table ip_tables: iptables: counters copy to user failed while replacing table ip_tables: iptables: counters copy to user failed while replacing table Cannot find add_set index 0 as target Cannot find add_set index 0 as target Cannot find add_set index 0 as target hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected nla_parse: 11 callbacks suppressed netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready