vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd: release socket ====================================================== WARNING: possible circular locking dependency detected 4.19.195-syzkaller #0 Not tainted ------------------------------------------------------ kworker/0:1/14 is trying to acquire lock: 00000000e01f1b86 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] 00000000e01f1b86 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:578 but task is already holding lock: 00000000432d4d85 ((delayed_fput_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 ((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 -> #2 ((wq_completion)"events"){+.+.}: 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 -> #1 (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 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbf3/0x2be0 kernel/exit.c:870 vhci_hcd: disconnect device do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 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 -> #0 (&sb->s_type->i_mutex_key#13){+.+.}: down_write+0x34/0x90 kernel/locking/rwsem.c:70 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 other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#13 --> (wq_completion)"events" --> (delayed_fput_work).work Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((delayed_fput_work).work); lock((wq_completion)"events"); lock((delayed_fput_work).work); lock(&sb->s_type->i_mutex_key#13); *** DEADLOCK *** 2 locks held by kworker/0:1/14: #0: 000000001e91a239 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000432d4d85 ((delayed_fput_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 stack backtrace: CPU: 0 PID: 14 Comm: kworker/0:1 Not tainted 4.19.195-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events delayed_fput 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 down_write+0x34/0x90 kernel/locking/rwsem.c:70 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 vhci_hcd vhci_hcd.0: pdev(0) rhport(1) sockfd(4) vhci_hcd vhci_hcd.0: devid(0) speed(3) speed_str(high-speed) vhci_hcd vhci_hcd.0: Device attached vhci_hcd: connection closed vhci_hcd: stop threads vhci_hcd: release socket vhci_hcd: disconnect device overlayfs: unrecognized mount option "permit_directio" or missing value overlayfs: unrecognized mount option "permit_directio" or missing value EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs (loop5): Unrecognized mount option "rcp 1.$|5^~tŶ/$" or missing value EXT4-fs (loop5): failed to parse options in superblock: rcp 1.$|5^~tŶ/$ EXT4-fs (loop5): Unrecognized mount option "6|;^GzLo3ͽϷ97b ;Um_l҄`<$/1rcp 1.$|5^~tŶ/$" or missing value EXT4-fs (loop5): Unrecognized mount option "rcp 1.$|5^~tŶ/$" or missing value EXT4-fs (loop5): failed to parse options in superblock: rcp 1.$|5^~tŶ/$ EXT4-fs (loop5): Unrecognized mount option "6|;^GzLo3ͽϷ97b ;Um_l҄`<$/1rcp 1.$|5^~tŶ/$" or missing value loop4: p2 < > p3 p4 loop4: partition table partially beyond EOD, truncated loop4: p2 size 2 extends beyond EOD, truncated loop4: p3 start 225 is beyond EOD, truncated loop4: p4 size 3657465856 extends beyond EOD, truncated tmpfs: No value for mount option 'h%' 9pnet: Insufficient options for proto=fd overlayfs: failed to resolve './file1': -2 overlayfs: workdir and upperdir must reside under the same mount tmpfs: No value for mount option 'h%' 9pnet: Insufficient options for proto=fd ieee80211 phy34: Selected rate control algorithm 'minstrel_ht' ISO 9660 Extensions: Microsoft Joliet Level 0 ISOFS: File unit size != 0 for ISO file (1792). netlink: 20 bytes leftover after parsing attributes in process `syz-executor.1'. overlayfs: fs on './file0' does not support file handles, falling back to index=off,nfs_export=off. ADFS-fs: unrecognised mount option "overlay" or missing value overlayfs: invalid redirect (./file0) EXT4-fs (loop5): mounted filesystem without journal. Opts: ,errors=continue ieee80211 phy35: Selected rate control algorithm 'minstrel_ht' overlayfs: maximum fs stacking depth exceeded overlayfs: filesystem on './bus' not supported as upperdir ADFS-fs: unrecognised mount option "overlay" or missing value audit: type=1804 audit(1624952954.504:100): pid=24496 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir750103207/syzkaller.CxCjrZ/500/bus" dev="sda1" ino=14051 res=1 ieee80211 phy36: Selected rate control algorithm 'minstrel_ht' audit: type=1804 audit(1624952954.534:101): pid=24496 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir750103207/syzkaller.CxCjrZ/500/bus" dev="sda1" ino=14051 res=1 audit: type=1804 audit(1624952954.534:102): pid=24496 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.4" name="/root/syzkaller-testdir750103207/syzkaller.CxCjrZ/500/bus" dev="sda1" ino=14051 res=1 UDF-fs: bad mount option "volume=00000000004294967297" or missing value netlink: 20 bytes leftover after parsing attributes in process `syz-executor.1'. Bluetooth: hci0: command 0x0406 tx timeout audit: type=1804 audit(1624952954.964:103): pid=24496 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir750103207/syzkaller.CxCjrZ/500/bus" dev="sda1" ino=14051 res=1 EXT4-fs (loop5): mounted filesystem without journal. Opts: ,errors=continue ISO 9660 Extensions: Microsoft Joliet Level 0 audit: type=1804 audit(1624952955.014:104): pid=24553 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir750103207/syzkaller.CxCjrZ/500/bus" dev="sda1" ino=14051 res=1 ieee80211 phy37: Selected rate control algorithm 'minstrel_ht' UDF-fs: bad mount option "volume=00000000004294967297" or missing value audit: type=1804 audit(1624952955.014:105): pid=24553 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.4" name="/root/syzkaller-testdir750103207/syzkaller.CxCjrZ/500/bus" dev="sda1" ino=14051 res=1 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 overlayfs: unrecognized mount option "upperdhr=./file1" or missing value netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. UDF-fs: bad mount option "volume=00000000004294967297" or missing value TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. IPv6: ADDRCONF(NETDEV_UP): vlan2: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready device bridge_slave_0 left promiscuous mode bridge0: port 1(bridge_slave_0) entered disabled state device bridge_slave_1 left promiscuous mode bridge0: port 2(bridge_slave_1) entered disabled state bond0: Releasing backup interface bond_slave_0 bond0: Releasing backup interface bond_slave_1 team0: Port device team_slave_0 removed team0: Port device team_slave_1 removed TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. batman_adv: batadv0: Interface deactivated: batadv_slave_0 batman_adv: batadv0: Removing interface: batadv_slave_0 batman_adv: batadv0: Interface deactivated: batadv_slave_1 batman_adv: batadv0: Removing interface: batadv_slave_1 ieee80211 phy38: Selected rate control algorithm 'minstrel_ht' IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) ieee80211 phy39: Selected rate control algorithm 'minstrel_ht' ieee80211 phy40: Selected rate control algorithm 'minstrel_ht' ieee80211 phy41: Selected rate control algorithm 'minstrel_ht' device veth1_macvtap left promiscuous mode device veth0_macvtap left promiscuous mode device veth1_vlan left promiscuous mode device veth0_vlan left promiscuous mode ISO 9660 Extensions: Microsoft Joliet Level 0 ISOFS: File unit size != 0 for ISO file (1792). hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected ISO 9660 Extensions: Microsoft Joliet Level 0 ISOFS: File unit size != 0 for ISO file (1792). hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected