syzbot

block nbd0: Receive control failed (result -107)
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
kworker/u9:3/5993 is trying to acquire lock:
ffff88801c36d1e0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
ffff88801c36d1e0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: inet_shutdown+0x67/0x410 net/ipv4/af_inet.c:919

but task is already holding lock:
ffff888078118c70 (&nsock->tx_lock){+.+.}-{4:4}, at: recv_work+0x5e7/0x8c0 drivers/block/nbd.c:1020

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #6 (&nsock->tx_lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
       nbd_handle_cmd drivers/block/nbd.c:1143 [inline]
       nbd_queue_rq+0x428/0x1080 drivers/block/nbd.c:1207
       blk_mq_dispatch_rq_list+0x422/0x1e70 block/blk-mq.c:2148
       __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
       blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
       __blk_mq_sched_dispatch_requests+0xcea/0x1620 block/blk-mq-sched.c:307
       blk_mq_sched_dispatch_requests+0xd7/0x1c0 block/blk-mq-sched.c:329
       blk_mq_run_hw_queue+0x23c/0x670 block/blk-mq.c:2386
       blk_mq_dispatch_list+0x51d/0x1360 block/blk-mq.c:2949
       blk_mq_flush_plug_list block/blk-mq.c:2997 [inline]
       blk_mq_flush_plug_list+0x130/0x600 block/blk-mq.c:2969
       __blk_flush_plug+0x2c4/0x4b0 block/blk-core.c:1230
       blk_finish_plug block/blk-core.c:1257 [inline]
       __submit_bio+0x584/0x6c0 block/blk-core.c:649
       __submit_bio_noacct_mq block/blk-core.c:722 [inline]
       submit_bio_noacct_nocheck+0x562/0xc10 block/blk-core.c:753
       submit_bio_noacct+0xd17/0x2010 block/blk-core.c:884
       blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline]
       submit_bh_wbc+0x59c/0x770 fs/buffer.c:2821
       submit_bh fs/buffer.c:2826 [inline]
       block_read_full_folio+0x264/0x8e0 fs/buffer.c:2444
       filemap_read_folio+0xfc/0x3b0 mm/filemap.c:2501
       do_read_cache_folio+0x2d7/0x6b0 mm/filemap.c:4101
       read_mapping_folio include/linux/pagemap.h:1028 [inline]
       read_part_sector+0xd1/0x370 block/partitions/core.c:723
       adfspart_check_ICS+0x93/0x910 block/partitions/acorn.c:360
       check_partition block/partitions/core.c:142 [inline]
       blk_add_partitions block/partitions/core.c:590 [inline]
       bdev_disk_changed+0x7f8/0xc80 block/partitions/core.c:694
       blkdev_get_whole+0x187/0x290 block/bdev.c:764
       bdev_open+0x2c7/0xe40 block/bdev.c:973
       blkdev_open+0x34e/0x4f0 block/fops.c:697
       do_dentry_open+0x6d8/0x1660 fs/open.c:949
       vfs_open+0x82/0x3f0 fs/open.c:1081
       do_open fs/namei.c:4671 [inline]
       path_openat+0x208c/0x31a0 fs/namei.c:4830
       do_file_open+0x20e/0x430 fs/namei.c:4859
       do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
       do_sys_open fs/open.c:1372 [inline]
       __do_sys_openat fs/open.c:1388 [inline]
       __se_sys_openat fs/open.c:1383 [inline]
       __x64_sys_openat+0x12d/0x210 fs/open.c:1383
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #5 (&cmd->lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
       nbd_queue_rq+0xba/0x1080 drivers/block/nbd.c:1199
       blk_mq_dispatch_rq_list+0x422/0x1e70 block/blk-mq.c:2148
       __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
       blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
       __blk_mq_sched_dispatch_requests+0xcea/0x1620 block/blk-mq-sched.c:307
       blk_mq_sched_dispatch_requests+0xd7/0x1c0 block/blk-mq-sched.c:329
       blk_mq_run_hw_queue+0x23c/0x670 block/blk-mq.c:2386
       blk_mq_dispatch_list+0x51d/0x1360 block/blk-mq.c:2949
       blk_mq_flush_plug_list block/blk-mq.c:2997 [inline]
       blk_mq_flush_plug_list+0x130/0x600 block/blk-mq.c:2969
       __blk_flush_plug+0x2c4/0x4b0 block/blk-core.c:1230
       blk_finish_plug block/blk-core.c:1257 [inline]
       __submit_bio+0x584/0x6c0 block/blk-core.c:649
       __submit_bio_noacct_mq block/blk-core.c:722 [inline]
       submit_bio_noacct_nocheck+0x562/0xc10 block/blk-core.c:753
       submit_bio_noacct+0xd17/0x2010 block/blk-core.c:884
       blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline]
       submit_bh_wbc+0x59c/0x770 fs/buffer.c:2821
       submit_bh fs/buffer.c:2826 [inline]
       block_read_full_folio+0x264/0x8e0 fs/buffer.c:2444
       filemap_read_folio+0xfc/0x3b0 mm/filemap.c:2501
       do_read_cache_folio+0x2d7/0x6b0 mm/filemap.c:4101
       read_mapping_folio include/linux/pagemap.h:1028 [inline]
       read_part_sector+0xd1/0x370 block/partitions/core.c:723
       adfspart_check_ICS+0x93/0x910 block/partitions/acorn.c:360
       check_partition block/partitions/core.c:142 [inline]
       blk_add_partitions block/partitions/core.c:590 [inline]
       bdev_disk_changed+0x7f8/0xc80 block/partitions/core.c:694
       blkdev_get_whole+0x187/0x290 block/bdev.c:764
       bdev_open+0x2c7/0xe40 block/bdev.c:973
       blkdev_open+0x34e/0x4f0 block/fops.c:697
       do_dentry_open+0x6d8/0x1660 fs/open.c:949
       vfs_open+0x82/0x3f0 fs/open.c:1081
       do_open fs/namei.c:4671 [inline]
       path_openat+0x208c/0x31a0 fs/namei.c:4830
       do_file_open+0x20e/0x430 fs/namei.c:4859
       do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
       do_sys_open fs/open.c:1372 [inline]
       __do_sys_openat fs/open.c:1388 [inline]
       __se_sys_openat fs/open.c:1383 [inline]
       __x64_sys_openat+0x12d/0x210 fs/open.c:1383
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #4 (set->srcu){.+.+}-{0:0}:
       srcu_lock_sync include/linux/srcu.h:199 [inline]
       __synchronize_srcu+0xa1/0x2a0 kernel/rcu/srcutree.c:1505
       blk_mq_wait_quiesce_done block/blk-mq.c:284 [inline]
       blk_mq_wait_quiesce_done block/blk-mq.c:281 [inline]
       blk_mq_quiesce_queue block/blk-mq.c:304 [inline]
       blk_mq_quiesce_queue+0x149/0x1c0 block/blk-mq.c:299
       elevator_switch+0x17b/0x7e0 block/elevator.c:576
       elevator_change+0x352/0x530 block/elevator.c:681
       elevator_set_default+0x29e/0x360 block/elevator.c:754
       blk_register_queue+0x412/0x590 block/blk-sysfs.c:946
       __add_disk+0x73f/0xe40 block/genhd.c:528
       add_disk_fwnode+0x118/0x5c0 block/genhd.c:597
       add_disk include/linux/blkdev.h:785 [inline]
       nbd_dev_add+0x77a/0xb10 drivers/block/nbd.c:1984
       nbd_init+0x291/0x2b0 drivers/block/nbd.c:2692
       do_one_initcall+0x11d/0x760 init/main.c:1382
       do_initcall_level init/main.c:1444 [inline]
       do_initcalls init/main.c:1460 [inline]
       do_basic_setup init/main.c:1479 [inline]
       kernel_init_freeable+0x6e5/0x7a0 init/main.c:1692
       kernel_init+0x1f/0x1e0 init/main.c:1582
       ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #3 (&q->elevator_lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776
       elevator_change+0x1bc/0x530 block/elevator.c:679
       elevator_set_none+0x92/0xf0 block/elevator.c:769
       blk_mq_elv_switch_none block/blk-mq.c:5110 [inline]
       __blk_mq_update_nr_hw_queues block/blk-mq.c:5155 [inline]
       blk_mq_update_nr_hw_queues+0x4c1/0x15f0 block/blk-mq.c:5220
       nbd_start_device+0x1a6/0xbd0 drivers/block/nbd.c:1489
       nbd_genl_connect+0xff2/0x1a40 drivers/block/nbd.c:2239
       genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114
       genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
       genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209
       netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550
       genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
       netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
       netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
       netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
       sock_sendmsg_nosec net/socket.c:727 [inline]
       __sock_sendmsg net/socket.c:742 [inline]
       ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2592
       ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
       __sys_sendmsg+0x170/0x220 net/socket.c:2678
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&q->q_usage_counter(io)#49){++++}-{0:0}:
       blk_alloc_queue+0x610/0x790 block/blk-core.c:461
       blk_mq_alloc_queue+0x174/0x290 block/blk-mq.c:4429
       __blk_mq_alloc_disk+0x29/0x120 block/blk-mq.c:4476
       nbd_dev_add+0x492/0xb10 drivers/block/nbd.c:1954
       nbd_init+0x291/0x2b0 drivers/block/nbd.c:2692
       do_one_initcall+0x11d/0x760 init/main.c:1382
       do_initcall_level init/main.c:1444 [inline]
       do_initcalls init/main.c:1460 [inline]
       do_basic_setup init/main.c:1479 [inline]
       kernel_init_freeable+0x6e5/0x7a0 init/main.c:1692
       kernel_init+0x1f/0x1e0 init/main.c:1582
       ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #1 (fs_reclaim){+.+.}-{0:0}:
       __fs_reclaim_acquire mm/page_alloc.c:4348 [inline]
       fs_reclaim_acquire+0xc4/0x100 mm/page_alloc.c:4362
       might_alloc include/linux/sched/mm.h:317 [inline]
       slab_pre_alloc_hook mm/slub.c:4489 [inline]
       slab_alloc_node mm/slub.c:4843 [inline]
       kmem_cache_alloc_node_noprof+0x53/0x6f0 mm/slub.c:4918
       __alloc_skb+0x140/0x710 net/core/skbuff.c:702
       alloc_skb include/linux/skbuff.h:1383 [inline]
       __ip6_append_data+0x36c0/0x4dc0 net/ipv6/ip6_output.c:1669
       ip6_append_data net/ipv6/ip6_output.c:1857 [inline]
       ip6_append_data+0x10b/0x410 net/ipv6/ip6_output.c:1826
       rawv6_sendmsg+0x169c/0x4420 net/ipv6/raw.c:912
       inet_sendmsg+0x11c/0x140 net/ipv4/af_inet.c:865
       sock_sendmsg_nosec net/socket.c:727 [inline]
       __sock_sendmsg net/socket.c:742 [inline]
       ____sys_sendmsg+0x98d/0xb70 net/socket.c:2592
       ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
       __sys_sendmsg+0x170/0x220 net/socket.c:2678
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sk_lock-AF_INET6){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
       lock_acquire kernel/locking/lockdep.c:5868 [inline]
       lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
       lock_sock_nested+0x41/0xf0 net/core/sock.c:3780
       lock_sock include/net/sock.h:1709 [inline]
       inet_shutdown+0x67/0x410 net/ipv4/af_inet.c:919
       nbd_mark_nsock_dead+0xae/0x5c0 drivers/block/nbd.c:318
       recv_work+0x5fb/0x8c0 drivers/block/nbd.c:1021
       process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
       process_scheduled_works kernel/workqueue.c:3359 [inline]
       worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
       kthread+0x370/0x450 kernel/kthread.c:436
       ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

other info that might help us debug this:

Chain exists of:
  sk_lock-AF_INET6 --> &cmd->lock --> &nsock->tx_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&nsock->tx_lock);
                               lock(&cmd->lock);
                               lock(&nsock->tx_lock);
  lock(sk_lock-AF_INET6);

 *** DEADLOCK ***

3 locks held by kworker/u9:3/5993:
 #0: ffff888027df4948 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90003347d08 ((work_completion)(&args->work)#3){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff888078118c70 (&nsock->tx_lock){+.+.}-{4:4}, at: recv_work+0x5e7/0x8c0 drivers/block/nbd.c:1020

stack backtrace:
CPU: 0 UID: 0 PID: 5993 Comm: kworker/u9:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: nbd0-recv recv_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043
 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x14b8/0x2630 kernel/locking/lockdep.c:5237
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
 lock_sock_nested+0x41/0xf0 net/core/sock.c:3780
 lock_sock include/net/sock.h:1709 [inline]
 inet_shutdown+0x67/0x410 net/ipv4/af_inet.c:919
 nbd_mark_nsock_dead+0xae/0x5c0 drivers/block/nbd.c:318
 recv_work+0x5fb/0x8c0 drivers/block/nbd.c:1021
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
block nbd2: Receive control failed (result -32)
block nbd3: Receive control failed (result -32)
block nbd4: Receive control failed (result -32)
block nbd5: Receive control failed (result -32)
block nbd6: Receive control failed (result -104)
block nbd0: Receive control failed (result -107)
block nbd8: Receive control failed (result -104)
block nbd0: Receive control failed (result -107)
block nbd0: Receive control failed (result -107)
Bluetooth: hci0: command tx timeout
block nbd0: Receive control failed (result -107)
block nbd12: Receive control failed (result -32)
block nbd13: Receive control failed (result -32)
block nbd14: Receive control failed (result -32)
block nbd15: Receive control failed (result -32)
block nbd16: Receive control failed (result -32)
block nbd17: Receive control failed (result -32)
block nbd0: Receive control failed (result -107)
block nbd19: Receive control failed (result -32)
block nbd20: Receive control failed (result -32)
block nbd0: Receive control failed (result -107)
block nbd0: Receive control failed (result -107)
block nbd23: Receive control failed (result -32)
block nbd24: Receive control failed (result -32)
block nbd25: Receive control failed (result -32)
block nbd0: Receive control failed (result -107)
block nbd27: Receive control failed (result -32)
block nbd28: Receive control failed (result -32)
block nbd29: Receive control failed (result -32)
block nbd30: Receive control failed (result -32)
block nbd31: Receive control failed (result -32)
block nbd32: Receive control failed (result -32)
block nbd33: Receive control failed (result -32)
block nbd0: Receive control failed (result -107)