WARNING: suspicious RCU usage 5.8.0-rc7-syzkaller #0 Not tainted ----------------------------- net/openvswitch/flow_table.c:940 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by syz-executor.1/10282: #0: ffffffff8a832390 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:741 #1: ffffffff8aa792e8 (ovs_mutex){+.+.}-{3:3}, at: ovs_lock net/openvswitch/datapath.c:105 [inline] #1: ffffffff8aa792e8 (ovs_mutex){+.+.}-{3:3}, at: ovs_dp_cmd_new+0x4db/0xea0 net/openvswitch/datapath.c:1707 stack backtrace: CPU: 0 PID: 10282 Comm: syz-executor.1 Not tainted 5.8.0-rc7-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 ovs_flow_tbl_masks_cache_size+0xc3/0xe0 net/openvswitch/flow_table.c:940 ovs_dp_cmd_fill_info+0x4e4/0x880 net/openvswitch/datapath.c:1539 ovs_dp_cmd_new+0x584/0xea0 net/openvswitch/datapath.c:1728 genl_family_rcv_msg_doit net/netlink/genetlink.c:669 [inline] genl_family_rcv_msg net/netlink/genetlink.c:714 [inline] genl_rcv_msg+0x61d/0x980 net/netlink/genetlink.c:731 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470 genl_rcv+0x24/0x40 net/netlink/genetlink.c:742 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2359 ___sys_sendmsg+0xf3/0x170 net/socket.c:2413 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2446 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45ccd9 Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f16bb795c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002bec0 RCX: 000000000045ccd9 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007ffc07116c8f R14: 00007f16bb7969c0 R15: 000000000078bf0c