block nbd2: shutting down sockets ====================================================== WARNING: possible circular locking dependency detected 4.14.307-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/10941 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.2/10941: #0: (&nbd->config_lock){+.+.}, at: [] nbd_ioctl+0x11f/0xad0 drivers/block/nbd.c:1369 stack backtrace: CPU: 0 PID: 10941 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: 0033:0x7fb256bb30f9 RSP: 002b:00007fb255125168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb256cd2f80 RCX: 00007fb256bb30f9 RDX: 0000000000000000 RSI: 000000000000ab04 RDI: 0000000000000003 RBP: 00007fb256c0eae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc98a2aacf R14: 00007fb255125300 R15: 0000000000022000 Bluetooth: hci0 command 0x0401 tx timeout EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue XFS (loop5): Superblock has unknown incompatible features (0x8) enabled. XFS (loop5): Filesystem can not be safely mounted by this kernel. XFS (loop5): SB validate failed with error -22. misc userio: The device must be registered before sending interrupts unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 caif:caif_disconnect_client(): nothing to disconnect caif:caif_disconnect_client(): nothing to disconnect XFS (loop1): Mounting V4 Filesystem XFS (loop1): Ending clean mount audit: type=1804 audit(3825546884.498:3): pid=11476 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.1" name="/root/syzkaller-testdir2501015317/syzkaller.7Jo1zI/121/bus/bus" dev="loop1" ino=41 res=1 audit: type=1804 audit(3825546884.578:4): pid=11545 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.1" name="/root/syzkaller-testdir2501015317/syzkaller.7Jo1zI/121/bus/bus" dev="loop1" ino=41 res=1 syz-executor.1 (11476) used greatest stack depth: 23864 bytes left XFS (loop1): Unmounting Filesystem XFS (loop1): Mounting V4 Filesystem XFS (loop1): Ending clean mount audit: type=1804 audit(3825546885.328:5): pid=11599 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.1" name="/root/syzkaller-testdir2501015317/syzkaller.7Jo1zI/122/bus/bus" dev="loop1" ino=41 res=1 audit: type=1804 audit(3825546885.378:6): pid=11622 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.1" name="/root/syzkaller-testdir2501015317/syzkaller.7Jo1zI/122/bus/bus" dev="loop1" ino=41 res=1 XFS (loop1): Unmounting Filesystem XFS (loop1): Mounting V4 Filesystem XFS (loop1): Ending clean mount audit: type=1804 audit(3825546885.678:7): pid=11672 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.1" name="/root/syzkaller-testdir2501015317/syzkaller.7Jo1zI/123/bus/bus" dev="loop1" ino=41 res=1 audit: type=1804 audit(3825546885.748:8): pid=11671 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.1" name="/root/syzkaller-testdir2501015317/syzkaller.7Jo1zI/123/bus/bus" dev="loop1" ino=41 res=1 XFS (loop1): Unmounting Filesystem vhci_hcd vhci_hcd.0: pdev(4) rhport(0) sockfd(3) vhci_hcd vhci_hcd.0: devid(0) speed(3) speed_str(high-speed) vhci_hcd vhci_hcd.0: Device attached audit: type=1804 audit(3825546886.068:9): pid=11774 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir2107535510/syzkaller.mXCsWw/127/file0" dev="sda1" ino=14050 res=1 vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd: release socket vhci_hcd: disconnect device audit: type=1804 audit(3825546886.688:10): pid=11817 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir4127180451/syzkaller.ci5PFz/130/file0" dev="sda1" ino=14021 res=1 audit: type=1804 audit(3825546886.728:11): pid=11820 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.1" name="/root/syzkaller-testdir2501015317/syzkaller.7Jo1zI/131/file0" dev="sda1" ino=14021 res=1 audit: type=1804 audit(1678063237.800:12): pid=11846 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir2663922306/syzkaller.mrOsyY/114/file0" dev="sda1" ino=13899 res=1 EXT4-fs (loop5): couldn't mount RDWR because of unsupported optional features (8000) ISO 9660 Extensions: Microsoft Joliet Level 3 ISOFS: changing to secondary root ISO 9660 Extensions: Microsoft Joliet Level 3 ISOFS: changing to secondary root ISO 9660 Extensions: Microsoft Joliet Level 3 ISOFS: changing to secondary root