====================================================== WARNING: possible circular locking dependency detected 4.14.307-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/12589 is trying to acquire lock: (&bdev->bd_mutex){+.+.}, at: [] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 but task is already holding lock: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xad0 drivers/block/nbd.c:1369 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&nbd->config_lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 nbd_open+0x1ac/0x370 drivers/block/nbd.c:1422 __blkdev_get+0x306/0x1090 fs/block_dev.c:1470 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 -> #1 (nbd_index_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 nbd_open+0x1e/0x370 drivers/block/nbd.c:1409 __blkdev_get+0x306/0x1090 fs/block_dev.c:1470 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 -> #0 (&bdev->bd_mutex){+.+.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 nbd_bdev_reset drivers/block/nbd.c:1076 [inline] nbd_clear_sock_ioctl drivers/block/nbd.c:1282 [inline] __nbd_ioctl drivers/block/nbd.c:1306 [inline] nbd_ioctl+0x802/0xad0 drivers/block/nbd.c:1376 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 other info that might help us debug this: Chain exists of: &bdev->bd_mutex --> nbd_index_mutex --> &nbd->config_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&nbd->config_lock); lock(nbd_index_mutex); lock(&nbd->config_lock); lock(&bdev->bd_mutex); *** DEADLOCK *** 1 lock held by syz-executor.2/12589: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xad0 drivers/block/nbd.c:1369 stack backtrace: CPU: 0 PID: 12589 Comm: syz-executor.2 Not tainted 4.14.307-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 nbd_bdev_reset drivers/block/nbd.c:1076 [inline] nbd_clear_sock_ioctl drivers/block/nbd.c:1282 [inline] __nbd_ioctl drivers/block/nbd.c:1306 [inline] nbd_ioctl+0x802/0xad0 drivers/block/nbd.c:1376 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x540/0x1830 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1893 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 RIP: 0033:0x7fba1487b0f9 RSP: 002b:00007fba12ded168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fba1499af80 RCX: 00007fba1487b0f9 RDX: 0000000000000000 RSI: 000000000000ab04 RDI: 0000000000000003 RBP: 00007fba148d6ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdcb3f57df R14: 00007fba12ded300 R15: 0000000000022000 Bearer rejected, not supported in standalone mode ====================================================== WARNING: the mand mount option is being deprecated and will be removed in v5.15! ====================================================== unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 caif:caif_disconnect_client(): nothing to disconnect XFS (loop0): Invalid device [./file0], error=-15 kauditd_printk_skb: 3 callbacks suppressed audit: type=1326 audit(1678114325.608:15): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13087 comm="syz-executor.0" exe="/root/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f8d19dcf0f9 code=0x7ffc0000 batadv0: Invalid MTU 0 requested, hw min 68 audit: type=1326 audit(1678114325.608:16): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13087 comm="syz-executor.0" exe="/root/syz-executor.0" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f8d19dcf0f9 code=0x7ffc0000 audit: type=1326 audit(1678114325.718:17): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 Bluetooth: Unexpected continuation frame (len 18) audit: type=1326 audit(1678114325.718:18): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 audit: type=1326 audit(1678114325.718:19): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=160 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 audit: type=1326 audit(1678114325.718:20): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 audit: type=1326 audit(1678114325.718:21): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 audit: type=1326 audit(1678114325.718:22): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=319 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 audit: type=1326 audit(1678114325.718:23): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 audit: type=1326 audit(1678114325.718:24): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=13130 comm="syz-executor.5" exe="/root/syz-executor.5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f089723e0f9 code=0x7ffc0000 overlayfs: unrecognized mount option "xino=on" or missing value Bluetooth: hci2 command 0x0406 tx timeout 9pnet: Could not find request transport: fd+ netlink: 328 bytes leftover after parsing attributes in process `syz-executor.2'. 9pnet_virtio: no channels available for device 9pnet: Insufficient options for proto=fd IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready chnl_net:chnl_net_open(): err: Unable to register and open device, Err:-19 9pnet: Insufficient options for proto=fd caif:caif_disconnect_client(): nothing to disconnect chnl_net:chnl_flowctrl_cb(): NET flowctrl func called flow: CLOSE/DEINIT chnl_net:chnl_net_open(): state disconnected A link change request failed with some changes committed already. Interface caif0 may have been left with an inconsistent configuration, please check. overlayfs: unrecognized mount option "uppe@Û1\¶" or missing value overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "metacopy=on" or missing value overlayfs: unrecognized mount option "xino=auto" or missing value overlayfs: unrecognized mount option "metacopy=on" or missing value netlink: 12 bytes leftover after parsing attributes in process `syz-executor.5'. 9pnet: Insufficient options for proto=fd netlink: 224 bytes leftover after parsing attributes in process `syz-executor.1'.