ip6gre6: entered promiscuous mode
veth24: entered promiscuous mode
veth25: entered promiscuous mode
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.13934/9366 is trying to acquire lock:
ffffffff90094cc0 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_cache_noprof+0x61/0x600

but task is already holding lock:
ffff888100b2d760 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: vxlan_igmp_leave+0x306/0x450

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #7 (k-sk_lock-AF_INET){+.+.}-{0:0}:
       lock_sock_nested+0x41/0x100
       mptcp_listen+0x235/0x4a0
       __x64_sys_listen+0x1c7/0x240
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #6 (sk_lock-AF_INET){+.+.}-{0:0}:
       lock_sock_nested+0x41/0x100
       inet_shutdown+0x6a/0x390
       nbd_mark_nsock_dead+0x2cb/0x550
       recv_work+0x1d14/0x1e30
       process_scheduled_works+0xc3d/0x1630
       worker_thread+0xa47/0xfb0
       kthread+0x38b/0x480
       ret_from_fork+0x514/0xb70
       ret_from_fork_asm+0x1a/0x30

-> #5 (&nsock->tx_lock){+.+.}-{4:4}:
       __mutex_lock+0x197/0x15a0
       nbd_queue_rq+0x373/0xff0
       blk_mq_dispatch_rq_list+0x499/0x1990
       __blk_mq_sched_dispatch_requests+0xd36/0x1580
       blk_mq_sched_dispatch_requests+0xd7/0x190
       blk_mq_run_work_fn+0x167/0x2f0
       process_scheduled_works+0xc3d/0x1630
       worker_thread+0xa47/0xfb0
       kthread+0x38b/0x480
       ret_from_fork+0x514/0xb70
       ret_from_fork_asm+0x1a/0x30

-> #4 (&cmd->lock){+.+.}-{4:4}:
       __mutex_lock+0x197/0x15a0
       nbd_queue_rq+0xc1/0xff0
       blk_mq_dispatch_rq_list+0x499/0x1990
       __blk_mq_sched_dispatch_requests+0xd36/0x1580
       blk_mq_sched_dispatch_requests+0xd7/0x190
       blk_mq_run_work_fn+0x167/0x2f0
       process_scheduled_works+0xc3d/0x1630
       worker_thread+0xa47/0xfb0
       kthread+0x38b/0x480
       ret_from_fork+0x514/0xb70
       ret_from_fork_asm+0x1a/0x30

-> #3 (set->srcu){.+.+}-{0:0}:
       __synchronize_srcu+0xca/0x2f0
       elevator_switch+0x1e8/0x7b0
       elevator_change+0x2fa/0x480
       elevator_set_default+0x375/0x440
       blk_register_queue+0x404/0x4f0
       __add_disk+0x6b8/0xdb0
       add_disk_fwnode+0x100/0x3a0
       nbd_dev_add+0x733/0xb60
       nbd_init+0x168/0x1f0
       do_one_initcall+0x250/0x870
       do_initcall_level+0x10a/0x1a0
       do_initcalls+0x59/0xa0
       kernel_init_freeable+0x29d/0x3e0
       kernel_init+0x22/0x1d0
       ret_from_fork+0x514/0xb70
       ret_from_fork_asm+0x1a/0x30

-> #2 (&q->elevator_lock){+.+.}-{4:4}:
       __mutex_lock+0x197/0x15a0
       elevator_change+0x1af/0x480
       elevator_set_none+0xb5/0x140
       blk_mq_update_nr_hw_queues+0x5ef/0x19e0
       nbd_start_device+0x189/0xb30
       nbd_genl_connect+0x167d/0x1cd0
       genl_family_rcv_msg_doit+0x233/0x340
       genl_rcv_msg+0x614/0x7a0
       netlink_rcv_skb+0x226/0x4a0
       genl_rcv+0x28/0x40
       netlink_unicast+0x8ef/0xa80
       netlink_sendmsg+0x7f0/0xb20
       sock_sendmsg_nosec+0x14e/0x190
       ____sys_sendmsg+0x54e/0x850
       ___sys_sendmsg+0x2a5/0x360
       __x64_sys_sendmsg+0x1b1/0x290
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&q->q_usage_counter(io)#49){++++}-{0:0}:
       blk_alloc_queue+0x544/0x690
       __blk_mq_alloc_disk+0x194/0x390
       nbd_dev_add+0x494/0xb60
       nbd_init+0x168/0x1f0
       do_one_initcall+0x250/0x870
       do_initcall_level+0x10a/0x1a0
       do_initcalls+0x59/0xa0
       kernel_init_freeable+0x29d/0x3e0
       kernel_init+0x22/0x1d0
       ret_from_fork+0x514/0xb70
       ret_from_fork_asm+0x1a/0x30

-> #0 (fs_reclaim){+.+.}-{0:0}:
       __lock_acquire+0x164c/0x2de0
       lock_acquire+0x115/0x350
       fs_reclaim_acquire+0x71/0x100
       __kmalloc_cache_noprof+0x61/0x600
       __igmp_group_dropped+0x831/0x11a0
       __ip_mc_dec_group+0x1dd/0x3e0
       ip_mc_leave_group+0x3e9/0x4b0
       vxlan_igmp_leave+0x311/0x450
       vxlan_multicast_leave+0x2a5/0x840
       vxlan_stop+0x50/0xa0
       __dev_close_many+0x361/0x6e0
       __dev_change_flags+0x3f5/0x820
       netif_change_flags+0x7c/0x1b0
       do_setlink+0xdd6/0x47a0
       rtnl_newlink+0x147c/0x1c30
       rtnetlink_rcv_msg+0x802/0xc00
       netlink_rcv_skb+0x226/0x4a0
       netlink_unicast+0x8ef/0xa80
       netlink_sendmsg+0x7f0/0xb20
       sock_sendmsg_nosec+0x14e/0x190
       ____sys_sendmsg+0x54e/0x850
       ___sys_sendmsg+0x2a5/0x360
       __x64_sys_sendmsg+0x1b1/0x290
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  fs_reclaim --> sk_lock-AF_INET --> k-sk_lock-AF_INET

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(k-sk_lock-AF_INET);
                               lock(sk_lock-AF_INET);
                               lock(k-sk_lock-AF_INET);
  lock(fs_reclaim);

 *** DEADLOCK ***

locks held by syz.0.13934/9366: 2, last CPU#1:
 #0: ffffffff9148c460 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc1d/0x1c30
 #1: ffff888100b2d760 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: vxlan_igmp_leave+0x306/0x450

stack backtrace:
CPU: 1 UID: 0 PID: 9366 Comm: syz.0.13934 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_circular_bug+0x2e2/0x300
 check_noncircular+0x12f/0x150
 __lock_acquire+0x164c/0x2de0
 lock_acquire+0x115/0x350
 fs_reclaim_acquire+0x71/0x100
 __kmalloc_cache_noprof+0x61/0x600
 __igmp_group_dropped+0x831/0x11a0
 __ip_mc_dec_group+0x1dd/0x3e0
 ip_mc_leave_group+0x3e9/0x4b0
 vxlan_igmp_leave+0x311/0x450
 vxlan_multicast_leave+0x2a5/0x840
 vxlan_stop+0x50/0xa0
 __dev_close_many+0x361/0x6e0
 __dev_change_flags+0x3f5/0x820
 netif_change_flags+0x7c/0x1b0
 do_setlink+0xdd6/0x47a0
 rtnl_newlink+0x147c/0x1c30
 rtnetlink_rcv_msg+0x802/0xc00
 netlink_rcv_skb+0x226/0x4a0
 netlink_unicast+0x8ef/0xa80
 netlink_sendmsg+0x7f0/0xb20
 sock_sendmsg_nosec+0x14e/0x190
 ____sys_sendmsg+0x54e/0x850
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1b1/0x290
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4cc9f9f559
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4ccaeb7028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f4cca225fa0 RCX: 00007f4cc9f9f559
RDX: 0000000004000804 RSI: 0000200000000bc0 RDI: 000000000000000b
RBP: 00007f4cca036b20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4cca226038 R14: 00007f4cca225fa0 R15: 00007ffd2e772ea8
 </TASK>
syzkaller0: entered promiscuous mode
syzkaller0.1: entered promiscuous mode
bond21: entered promiscuous mode
ip6gretap2: entered promiscuous mode
gtp6: entered promiscuous mode
