============================= 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: UBIFS error (pid: 25208): cannot open "(null)", error -22 rcu_scheduler_active = 2, debug_locks = 1 4 locks held by kworker/u4:8/15990: #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: 15990 Comm: kworker/u4:8 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 netlink: 40 bytes leftover after parsing attributes in process `syz-executor.2'. UBIFS error (pid: 25222): cannot open "(null)", error -22 UBIFS error (pid: 25241): cannot open "(null)", error -22 netlink: 14 bytes leftover after parsing attributes in process `syz-executor.2'. IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state device bridge0 entered promiscuous mode netlink: 14 bytes leftover after parsing attributes in process `syz-executor.2'. bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state device bridge0 left promiscuous mode IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state device bridge0 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state device bridge0 left promiscuous mode IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state device bridge0 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state device bridge0 left promiscuous mode IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): bridge0: link becomes ready bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state device bridge0 entered promiscuous mode nla_parse: 2 callbacks suppressed netlink: 14 bytes leftover after parsing attributes in process `syz-executor.2'. bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state device bridge0 left promiscuous mode bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state device bridge0 entered promiscuous mode netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. mmap: syz-executor.3 (25414) uses deprecated remap_file_pages() syscall. See Documentation/vm/remap_file_pages.txt. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored new mount options do not match the existing superblock, will be ignored syz-executor.1 (25661) used greatest stack depth: 23520 bytes left 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 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 hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected