batman_adv: batadv0: Interface activated: batadv_slave_1 ====================================================== WARNING: possible circular locking dependency detected 5.5.0-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor284/9739 is trying to acquire lock: ffff8880a92a6128 ((wq_completion)wg-kex-wireguard0){+.+.}, at: flush_workqueue+0xf7/0x14c0 kernel/workqueue.c:2772 but task is already holding lock: ffff8880a2c50e80 (&wg->static_identity.lock){++++}, at: wg_set_device+0xe8b/0x1350 drivers/net/wireguard/netlink.c:567 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&wg->static_identity.lock){++++}: down_read+0x95/0x430 kernel/locking/rwsem.c:1495 wg_noise_handshake_create_initiation+0xc0/0x670 drivers/net/wireguard/noise.c:499 wg_packet_send_handshake_initiation+0x185/0x250 drivers/net/wireguard/send.c:34 wg_packet_handshake_send_worker+0x1d/0x30 drivers/net/wireguard/send.c:51 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 -> #1 ((work_completion)(&peer->transmit_handshake_work)){+.+.}: process_one_work+0x972/0x17a0 kernel/workqueue.c:2240 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 -> #0 ((wq_completion)wg-kex-wireguard0){+.+.}: check_prev_add kernel/locking/lockdep.c:2475 [inline] check_prevs_add kernel/locking/lockdep.c:2580 [inline] validate_chain kernel/locking/lockdep.c:2970 [inline] __lock_acquire+0x2596/0x4a00 kernel/locking/lockdep.c:3954 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 flush_workqueue+0x126/0x14c0 kernel/workqueue.c:2775 peer_remove_after_dead+0x16b/0x230 drivers/net/wireguard/peer.c:141 wg_peer_remove+0x244/0x340 drivers/net/wireguard/peer.c:176 wg_set_device+0xf76/0x1350 drivers/net/wireguard/netlink.c:575 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline] genl_family_rcv_msg net/netlink/genetlink.c:717 [inline] genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: (wq_completion)wg-kex-wireguard0 --> (work_completion)(&peer->transmit_handshake_work) --> &wg->static_identity.lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&wg->static_identity.lock); lock((work_completion)(&peer->transmit_handshake_work)); lock(&wg->static_identity.lock); lock((wq_completion)wg-kex-wireguard0); *** DEADLOCK *** 5 locks held by syz-executor284/9739: #0: ffffffff8a7899e8 (cb_lock){++++}, at: genl_rcv+0x1a/0x40 net/netlink/genetlink.c:744 #1: ffffffff8a789aa0 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8a789aa0 (genl_mutex){+.+.}, at: genl_rcv_msg+0x7de/0xea0 net/netlink/genetlink.c:732 #2: ffffffff8a733c80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 #3: ffff8880a2c510a0 (&wg->device_update_lock){+.+.}, at: wg_set_device+0x2be/0x1350 drivers/net/wireguard/netlink.c:510 #4: ffff8880a2c50e80 (&wg->static_identity.lock){++++}, at: wg_set_device+0xe8b/0x1350 drivers/net/wireguard/netlink.c:567 stack backtrace: CPU: 0 PID: 9739 Comm: syz-executor284 Not tainted 5.5.0-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+0x197/0x210 lib/dump_stack.c:118 print_circular_bug.isra.0.cold+0x163/0x172 kernel/locking/lockdep.c:1684 check_noncircular+0x32e/0x3e0 kernel/locking/lockdep.c:1808 check_prev_add kernel/locking/lockdep.c:2475 [inline] check_prevs_add kernel/locking/lockdep.c:2580 [inline] validate_chain kernel/locking/lockdep.c:2970 [inline] __lock_acquire+0x2596/0x4a00 kernel/locking/lockdep.c:3954 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 flush_workqueue+0x126/0x14c0 kernel/workqueue.c:2775 peer_remove_after_dead+0x16b/0x230 drivers/net/wireguard/peer.c:141 wg_peer_remove+0x244/0x340 drivers/net/wireguard/peer.c:176 wg_set_device+0xf76/0x1350 drivers/net/wireguard/netlink.c:575 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline] genl_family_rcv_msg net/netlink/genetlink.c:717 [inline] genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x446909 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 9b d4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff2cc3c8f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000003064 RCX: 0000000000446909 RDX: 0000000000000000 RSI: 0000000020001340 RDI: 0000000000000004 RBP: 7261756765726977 R08: 0000000000000000 R09: 0000000001bbbbbb R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000004042c0 R14: 0000000000000000 R15: 0000000000000000