input: syz1 as /devices/virtual/input/input6 IPVS: ftp: loaded support on port[0] = 21 usb usb18-port1: Cannot enable. Maybe the USB cable is bad? ====================================================== WARNING: possible circular locking dependency detected 4.19.195-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:2/36 is trying to acquire lock: 00000000b526f099 ((wq_completion)"events"){+.+.}, at: flush_workqueue+0xe8/0x13e0 kernel/workqueue.c:2658 but task is already holding lock: 0000000035c65e60 (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x8b0 net/core/net_namespace.c:520 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (pernet_ops_rwsem){++++}: unregister_netdevice_notifier+0x7b/0x330 net/core/dev.c:1708 raw_release+0x58/0x820 net/can/raw.c:358 __sock_release+0xcd/0x2a0 net/socket.c:579 sock_close+0x15/0x20 net/socket.c:1140 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&sb->s_type->i_mutex_key#13){+.+.}: inode_lock include/linux/fs.h:748 [inline] __sock_release+0x86/0x2a0 net/socket.c:578 sock_close+0x15/0x20 net/socket.c:1140 __fput+0x2ce/0x890 fs/file_table.c:278 delayed_fput+0x56/0x70 fs/file_table.c:304 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #1 ((delayed_fput_work).work){+.+.}: worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #0 ((wq_completion)"events"){+.+.}: flush_workqueue+0x117/0x13e0 kernel/workqueue.c:2661 flush_scheduled_work include/linux/workqueue.h:599 [inline] tipc_exit_net+0x38/0x60 net/tipc/core.c:100 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 other info that might help us debug this: Chain exists of: (wq_completion)"events" --> &sb->s_type->i_mutex_key#13 --> pernet_ops_rwsem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(pernet_ops_rwsem); lock(&sb->s_type->i_mutex_key#13); lock(pernet_ops_rwsem); lock((wq_completion)"events"); *** DEADLOCK *** 3 locks held by kworker/u4:2/36: #0: 0000000000542196 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000ba3e74f2 (net_cleanup_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 0000000035c65e60 (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x8b0 net/core/net_namespace.c:520 stack backtrace: CPU: 0 PID: 36 Comm: kworker/u4:2 Not tainted 4.19.195-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 flush_workqueue+0x117/0x13e0 kernel/workqueue.c:2661 flush_scheduled_work include/linux/workqueue.h:599 [inline] tipc_exit_net+0x38/0x60 net/tipc/core.c:100 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 9pnet: p9_fd_create_tcp (9956): problem connecting socket to 127.0.0.1 BTRFS: device fsid 5fb0fab3-7c4b-461e-bb1f-587512e1a79b devid 1 transid 7 /dev/loop2 9pnet: p9_fd_create_tcp (9960): problem connecting socket to 127.0.0.1 BTRFS error (device loop2): unsupported checksum algorithm 1 BTRFS error (device loop2): superblock checksum mismatch netlink: 40 bytes leftover after parsing attributes in process `syz-executor.1'. BTRFS error (device loop2): open_ctree failed netlink: 40 bytes leftover after parsing attributes in process `syz-executor.1'. BTRFS error (device loop2): unsupported checksum algorithm 1 BTRFS error (device loop2): superblock checksum mismatch usb usb18-port1: Cannot enable. Maybe the USB cable is bad? usb usb18-port1: unable to enumerate USB device BTRFS error (device loop2): open_ctree failed IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready mac80211_hwsim: wmediumd released netlink socket, switching to perfect channel medium UDF-fs: error (device loop2): udf_process_sequence: Primary Volume Descriptor not found! FAT-fs (loop4): Unrecognized mount option "utfTYK[:" or missing value UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2020/09/19 18:44 (1000) EXT4-fs (loop4): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs error (device loop4): __ext4_new_inode:922: comm syz-executor.4: reserved inode found cleared - inode=1 ptrace attach of "/root/syz-executor.0"[10117] was attempted by "/root/syz-executor.0"[10119] ieee802154 phy0 wpan0: encryption failed: -22 ieee802154 phy1 wpan1: encryption failed: -22 audit: type=1804 audit(1624902222.633:6): pid=10155 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.3" name="/root/syzkaller-testdir431597546/syzkaller.zkYBaq/10/file1/file0" dev="loop3" ino=4 res=1 FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop1): FAT read failed (blocknr 32) IPVS: ftp: loaded support on port[0] = 21 MTD: Attempt to mount non-MTD device "/dev/loop1" romfs: VFS: Can't find a romfs filesystem on dev loop1. FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) syz-executor.2 (10179) used greatest stack depth: 23624 bytes left FAT-fs (loop1): FAT read failed (blocknr 32) audit: type=1800 audit(1624902224.543:7): pid=10242 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="bus" dev="sda1" ino=13993 res=0 audit: type=1800 audit(1624902224.573:8): pid=10242 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="bus" dev="sda1" ino=13993 res=0 MTD: Attempt to mount non-MTD device "/dev/loop1" romfs: VFS: Can't find a romfs filesystem on dev loop1. FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop2): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) IPVS: ftp: loaded support on port[0] = 21 FAT-fs (loop1): FAT read failed (blocknr 32) FAT-fs (loop2): FAT read failed (blocknr 32) FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) tmpfs: No value for mount option '' FAT-fs (loop1): FAT read failed (blocknr 32) IPVS: ftp: loaded support on port[0] = 21 tmpfs: No value for mount option '' FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop1): FAT read failed (blocknr 32) IPVS: ftp: loaded support on port[0] = 21 MTD: Attempt to mount non-MTD device "/dev/loop1" EXT4-fs (loop4): VFS: Found ext4 filesystem with unknown checksum algorithm. romfs: VFS: Can't find a romfs filesystem on dev loop1. (syz-executor.4,10391,0):ocfs2_parse_options:1499 ERROR: Unrecognized mount option "ext4" or missing value (syz-executor.4,10391,0):ocfs2_fill_super:1225 ERROR: status = -22 FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop1): FAT read failed (blocknr 32) capability: warning: `syz-executor.5' uses 32-bit capabilities (legacy support in use) FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) Can't find ip_set type bitmap:ip FAT-fs (loop1): FAT read failed (blocknr 32) Bluetooth: hci6: Frame reassembly failed (-84)