Linux

In the Linux kernel, the following vulnerability has been resolved: f2fs: avoid infinite loop to flush node pages xfstests/generic/475 can give EIO all the time which give an infinite loop to flush node page like below. Let's avoid it. [16418.518551] Call Trace: [16418.518553] ? dm_submit_bio+0x48/0x400 [16418.518574] ? submit_bio_checks+0x1ac/0x5a0 [16418.525207] __submit_bio+0x1a9/0x230 [16418.525210] ? kmem_cache_alloc+0x29e/0x3c0 [16418.525223] submit_bio_noacct+0xa8/0x2b0 [16418.525226] submit_bio+0x4d/0x130 [16418.525238] __submit_bio+0x49/0x310 [f2fs] [16418.525339] ? bio_add_page+0x6a/0x90 [16418.525344] f2fs_submit_page_bio+0x134/0x1f0 [f2fs] [16418.525365] read_node_page+0x125/0x1b0 [f2fs] [16418.525388] __get_node_page.part.0+0x58/0x3f0 [f2fs] [16418.525409] __get_node_page+0x2f/0x60 [f2fs] [16418.525431] f2fs_get_dnode_of_data+0x423/0x860 [f2fs] [16418.525452] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [16418.525458] ? __mod_memcg_state.part.0+0x2a/0x30 [16418.525465] ? __mod_memcg_lruvec_state+0x27/0x40 [16418.525467] ? __xa_set_mark+0x57/0x70 [16418.525472] f2fs_do_write_data_page+0x10e/0x7b0 [f2fs] [16418.525493] f2fs_write_single_data_page+0x555/0x830 [f2fs] [16418.525514] ? sysvec_apic_timer_interrupt+0x4e/0x90 [16418.525518] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [16418.525523] f2fs_write_cache_pages+0x303/0x880 [f2fs] [16418.525545] ? blk_flush_plug_list+0x47/0x100 [16418.525548] f2fs_write_data_pages+0xfd/0x320 [f2fs] [16418.525569] do_writepages+0xd5/0x210 [16418.525648] filemap_fdatawrite_wbc+0x7d/0xc0 [16418.525655] filemap_fdatawrite+0x50/0x70 [16418.525658] f2fs_sync_dirty_inodes+0xa4/0x230 [f2fs] [16418.525679] f2fs_write_checkpoint+0x16d/0x1720 [f2fs] [16418.525699] ? ttwu_do_wakeup+0x1c/0x160 [16418.525709] ? ttwu_do_activate+0x6d/0xd0 [16418.525711] ? __wait_for_common+0x11d/0x150 [16418.525715] kill_f2fs_super+0xca/0x100 [f2fs] [16418.525733] deactivate_locked_super+0x3b/0xb0 [16418.525739] deactivate_super+0x40/0x50 [16418.525741] cleanup_mnt+0x139/0x190 [16418.525747] __cleanup_mnt+0x12/0x20 [16418.525749] task_work_run+0x6d/0xa0 [16418.525765] exit_to_user_mode_prepare+0x1ad/0x1b0 [16418.525771] syscall_exit_to_user_mode+0x27/0x50 [16418.525774] do_syscall_64+0x48/0xc0 [16418.525776] entry_SYSCALL_64_after_hwframe+0x44/0xaeShow less

In the Linux kernel, the following vulnerability has been resolved: NFSv4: Don't hold the layoutget locks across multiple RPC calls When doing layoutget as part of the open() compound, we have to be careful to release the layout locks before we can call any further RPC calls, such as setattr(). The reason is that those calls could trigger a recall, which could deadlock.Show less

In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8192e: Fix deadlock in rtllib_beacons_stop() There is a deadlock in rtllib_beacons_stop(), which is shown below: (Thread 1) | (Thread 2) | rtllib_send_beacon() rtllib_beacons_stop() | mod_timer() spin_lock_irqsave() //(1) | (wait a time) ... | rtllib_send_beacon_cb() del_timer_sync() | spin_lock_irqsave() //(2) (wait timer to stop) | ... We hold ieee->beacon_lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need ieee->beacon_lock in position (2) of thread 2. As a result, rtllib_beacons_stop() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_irqsave(), which could let timer handler to obtain the needed lock.Show less

In the Linux kernel, the following vulnerability has been resolved: tty: Fix a possible resource leak in icom_probe When pci_read_config_dword failed, call pci_release_regions() and pci_disable_device() to recycle the resource previously allocated.Show less

In the Linux kernel, the following vulnerability has been resolved: drivers: usb: host: Fix deadlock in oxu_bus_suspend() There is a deadlock in oxu_bus_suspend(), which is shown below: (Thread 1) | (Thread 2) | timer_action() oxu_bus_suspend() | mod_timer() spin_lock_irq() //(1) | (wait a time) ... | oxu_watchdog() del_timer_sync() | spin_lock_irq() //(2) (wait timer to stop) | ... We hold oxu->lock in position (1) of thread 1, and use del_timer_sync() to wait timer to stop, but timer handler also need oxu->lock in position (2) of thread 2. As a result, oxu_bus_suspend() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_irq(), which could let timer handler to obtain the needed lock.Show less

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8712: fix a potential memory leak in r871xu_drv_init() In r871xu_drv_init(), if r8712_init_drv_sw() fails, then the memory allocated by r8712_alloc_io_queue() in r8712_usb_dvobj_init() is not properly released as there is no action will be performed by r8712_usb_dvobj_deinit(). To properly release it, we should call r8712_free_io_queue() in r8712_usb_dvobj_deinit(). Besides, in r871xu_dev_remove(), r8712_usb_dvobj_deinit() will be called by r871x_dev_unload() under condition `padapter->bup` and r8712_free_io_queue() is called by r8712_free_drv_sw(). However, r8712_usb_dvobj_deinit() does not rely on `padapter->bup` and calling r8712_free_io_queue() in r8712_free_drv_sw() is negative for better understading the code. So I move r8712_usb_dvobj_deinit() into r871xu_dev_remove(), and remove r8712_free_io_queue() from r8712_free_drv_sw().Show less

In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8192bs: Fix deadlock in rtw_joinbss_event_prehandle() There is a deadlock in rtw_joinbss_event_prehandle(), which is shown below: (Thread 1) | (Thread 2) | _set_timer() rtw_joinbss_event_prehandle()| mod_timer() spin_lock_bh() //(1) | (wait a time) ... | _rtw_join_timeout_handler() del_timer_sync() | spin_lock_bh() //(2) (wait timer to stop) | ... We hold pmlmepriv->lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need pmlmepriv->lock in position (2) of thread 2. As a result, rtw_joinbss_event_prehandle() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_bh(), which could let timer handler to obtain the needed lock. What`s more, we change spin_lock_bh() to spin_lock_irq() in _rtw_join_timeout_handler() in order to prevent deadlock.Show less

In the Linux kernel, the following vulnerability has been resolved: char: xillybus: fix a refcount leak in cleanup_dev() usb_get_dev is called in xillyusb_probe. So it is better to call usb_put_dev before xdev is released.Show less

In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8723bs: Fix deadlock in rtw_surveydone_event_callback() There is a deadlock in rtw_surveydone_event_callback(), which is shown below: (Thread 1) | (Thread 2) | _set_timer() rtw_surveydone_event_callback()| mod_timer() spin_lock_bh() //(1) | (wait a time) ... | rtw_scan_timeout_handler() del_timer_sync() | spin_lock_bh() //(2) (wait timer to stop) | ... We hold pmlmepriv->lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need pmlmepriv->lock in position (2) of thread 2. As a result, rtw_surveydone_event_callback() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_bh(), which could let timer handler to obtain the needed lock. What`s more, we change spin_lock_bh() in rtw_scan_timeout_handler() to spin_lock_irq(). Otherwise, spin_lock_bh() will also cause deadlock() in timer handler.Show less

In the Linux kernel, the following vulnerability has been resolved: extcon: Modify extcon device to be created after driver data is set Currently, someone can invoke the sysfs such as state_show() intermittently before dev_set_drvdata() is done. And it can be a cause of kernel Oops because of edev is Null at that time. So modified the driver registration to after setting drviver data. - Oops's backtrace. Backtrace: [<c067865c>] (state_show) from [<c05222e8>] (dev_attr_show) [<c05222c0>] (dev_attr_show) from [<c02c66e0>] (sysfs_kf_seq_show) [<c02c6648>] (sysfs_kf_seq_show) from [<c02c496c>] (kernfs_seq_show) [<c02c4938>] (kernfs_seq_show) from [<c025e2a0>] (seq_read) [<c025e11c>] (seq_read) from [<c02c50a0>] (kernfs_fop_read) [<c02c5064>] (kernfs_fop_read) from [<c0231cac>] (__vfs_read) [<c0231c5c>] (__vfs_read) from [<c0231ee0>] (vfs_read) [<c0231e34>] (vfs_read) from [<c0232464>] (ksys_read) [<c02323f0>] (ksys_read) from [<c02324fc>] (sys_read) [<c02324e4>] (sys_read) from [<c00091d0>] (__sys_trace_return)Show less

In the Linux kernel, the following vulnerability has been resolved: tty: synclink_gt: Fix null-pointer-dereference in slgt_clean() When the driver fails at alloc_hdlcdev(), and then we remove the driver module, we will get the following splat: [ 25.065966] general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN PTI [ 25.066914] KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17] [ 25.069262] RIP: 0010:detach_hdlc_protocol+0x2a/0x3e0 [ 25.077709] Call Trace: [ 25.077924] <TASK> [ 25.078108] unregister_hdlc_device+0x16/0x30 [ 25.078481] slgt_cleanup+0x157/0x9f0 [synclink_gt] Fix this by checking whether the 'info->netdev' is a null pointer first.Show less

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: host: Stop setting the ACPI companion It is no longer needed. The sysdev pointer is now used when assigning the ACPI companions to the xHCI ports and USB devices. Assigning the ACPI companion here resulted in the fwnode->secondary pointer to be replaced also for the parent dwc3 device since the primary fwnode (the ACPI companion) was shared. That was unintentional and it created potential side effects like resource leaks.Show less

In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8192u: Fix deadlock in ieee80211_beacons_stop() There is a deadlock in ieee80211_beacons_stop(), which is shown below: (Thread 1) | (Thread 2) | ieee80211_send_beacon() ieee80211_beacons_stop() | mod_timer() spin_lock_irqsave() //(1) | (wait a time) ... | ieee80211_send_beacon_cb() del_timer_sync() | spin_lock_irqsave() //(2) (wait timer to stop) | ... We hold ieee->beacon_lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need ieee->beacon_lock in position (2) of thread 2. As a result, ieee80211_beacons_stop() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_irqsave(), which could let timer handler to obtain the needed lock.Show less

In the Linux kernel, the following vulnerability has been resolved: drivers: tty: serial: Fix deadlock in sa1100_set_termios() There is a deadlock in sa1100_set_termios(), which is shown below: (Thread 1) | (Thread 2) | sa1100_enable_ms() sa1100_set_termios() | mod_timer() spin_lock_irqsave() //(1) | (wait a time) ... | sa1100_timeout() del_timer_sync() | spin_lock_irqsave() //(2) (wait timer to stop) | ... We hold sport->port.lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need sport->port.lock in position (2) of thread 2. As a result, sa1100_set_termios() will block forever. This patch moves del_timer_sync() before spin_lock_irqsave() in order to prevent the deadlock.Show less

In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8192eu: Fix deadlock in rtw_joinbss_event_prehandle There is a deadlock in rtw_joinbss_event_prehandle(), which is shown below: (Thread 1) | (Thread 2) | _set_timer() rtw_joinbss_event_prehandle()| mod_timer() spin_lock_bh() //(1) | (wait a time) ... | rtw_join_timeout_handler() | _rtw_join_timeout_handler() del_timer_sync() | spin_lock_bh() //(2) (wait timer to stop) | ... We hold pmlmepriv->lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need pmlmepriv->lock in position (2) of thread 2. As a result, rtw_joinbss_event_prehandle() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_bh(), which could let timer handler to obtain the needed lock. What`s more, we change spin_lock_bh() to spin_lock_irq() in _rtw_join_timeout_handler() in order to prevent deadlock.Show less

In the Linux kernel, the following vulnerability has been resolved: USB: host: isp116x: check return value after calling platform_get_resource() It will cause null-ptr-deref if platform_get_resource() returns NULL, we need check the return value.Show less

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8712: fix uninit-value in usb_read8() and friends When r8712_usbctrl_vendorreq() returns negative, 'data' in usb_read{8,16,32} will not be initialized. BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:643 [inline] BUG: KMSAN: uninit-value in string+0x4ec/0x6f0 lib/vsprintf.c:725 string_nocheck lib/vsprintf.c:643 [inline] string+0x4ec/0x6f0 lib/vsprintf.c:725 vsnprintf+0x2222/0x3650 lib/vsprintf.c:2806 va_format lib/vsprintf.c:1704 [inline] pointer+0x18e6/0x1f70 lib/vsprintf.c:2443 vsnprintf+0x1a9b/0x3650 lib/vsprintf.c:2810 vprintk_store+0x537/0x2150 kernel/printk/printk.c:2158 vprintk_emit+0x28b/0xab0 kernel/printk/printk.c:2256 dev_vprintk_emit+0x5ef/0x6d0 drivers/base/core.c:4604 dev_printk_emit+0x1dd/0x21f drivers/base/core.c:4615 __dev_printk+0x3be/0x440 drivers/base/core.c:4627 _dev_info+0x1ea/0x22f drivers/base/core.c:4673 r871xu_drv_init+0x1929/0x3070 drivers/staging/rtl8712/usb_intf.c:401 usb_probe_interface+0xf19/0x1600 drivers/usb/core/driver.c:396 really_probe+0x6c7/0x1350 drivers/base/dd.c:621 __driver_probe_device+0x3e9/0x530 drivers/base/dd.c:752 driver_probe_device drivers/base/dd.c:782 [inline] __device_attach_driver+0x79f/0x1120 drivers/base/dd.c:899 bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427 __device_attach+0x593/0x8e0 drivers/base/dd.c:970 device_initial_probe+0x4a/0x60 drivers/base/dd.c:1017 bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487 device_add+0x1fff/0x26e0 drivers/base/core.c:3405 usb_set_configuration+0x37e9/0x3ed0 drivers/usb/core/message.c:2170 usb_generic_driver_probe+0x13c/0x300 drivers/usb/core/generic.c:238 usb_probe_device+0x309/0x570 drivers/usb/core/driver.c:293 really_probe+0x6c7/0x1350 drivers/base/dd.c:621 __driver_probe_device+0x3e9/0x530 drivers/base/dd.c:752 driver_probe_device drivers/base/dd.c:782 [inline] __device_attach_driver+0x79f/0x1120 drivers/base/dd.c:899 bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427 __device_attach+0x593/0x8e0 drivers/base/dd.c:970 device_initial_probe+0x4a/0x60 drivers/base/dd.c:1017 bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487 device_add+0x1fff/0x26e0 drivers/base/core.c:3405 usb_new_device+0x1b91/0x2950 drivers/usb/core/hub.c:2566 hub_port_connect drivers/usb/core/hub.c:5363 [inline] hub_port_connect_change drivers/usb/core/hub.c:5507 [inline] port_event drivers/usb/core/hub.c:5665 [inline] hub_event+0x58e3/0x89e0 drivers/usb/core/hub.c:5747 process_one_work+0xdb6/0x1820 kernel/workqueue.c:2289 worker_thread+0x10d0/0x2240 kernel/workqueue.c:2436 kthread+0x3c7/0x500 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 Local variable data created at: usb_read8+0x5d/0x130 drivers/staging/rtl8712/usb_ops.c:33 r8712_read8+0xa5/0xd0 drivers/staging/rtl8712/rtl8712_io.c:29 KMSAN: uninit-value in r871xu_drv_init https://syzkaller.appspot.com/bug?id=3cd92b1d85428b128503bfa7a250294c9ae00bd8Show less

In the Linux kernel, the following vulnerability has been resolved: nbd: fix race between nbd_alloc_config() and module removal When nbd module is being removing, nbd_alloc_config() may be called concurrently by nbd_genl_connect(), although try_module_get() will return false, but nbd_alloc_config() doesn't handle it. The race may lead to the leak of nbd_config and its related resources (e.g, recv_workq) and oops in nbd_read_stat() due to the unload of nbd module as shown below: BUG: kernel NULL pointer dereference, address: 0000000000000040 Oops: 0000 [#1] SMP PTI CPU: 5 PID: 13840 Comm: kworker/u17:33 Not tainted 5.14.0+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Workqueue: knbd16-recv recv_work [nbd] RIP: 0010:nbd_read_stat.cold+0x130/0x1a4 [nbd] Call Trace: recv_work+0x3b/0xb0 [nbd] process_one_work+0x1ed/0x390 worker_thread+0x4a/0x3d0 kthread+0x12a/0x150 ret_from_fork+0x22/0x30 Fixing it by checking the return value of try_module_get() in nbd_alloc_config(). As nbd_alloc_config() may return ERR_PTR(-ENODEV), assign nbd->config only when nbd_alloc_config() succeeds to ensure the value of nbd->config is binary (valid or NULL). Also adding a debug message to check the reference counter of nbd_config during module removal.Show less

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8712: fix uninit-value in r871xu_drv_init() When 'tmpU1b' returns from r8712_read8(padapter, EE_9346CR) is 0, 'mac[6]' will not be initialized. BUG: KMSAN: uninit-value in r871xu_drv_init+0x2d54/0x3070 drivers/staging/rtl8712/usb_intf.c:541 r871xu_drv_init+0x2d54/0x3070 drivers/staging/rtl8712/usb_intf.c:541 usb_probe_interface+0xf19/0x1600 drivers/usb/core/driver.c:396 really_probe+0x653/0x14b0 drivers/base/dd.c:596 __driver_probe_device+0x3e9/0x530 drivers/base/dd.c:752 driver_probe_device drivers/base/dd.c:782 [inline] __device_attach_driver+0x79f/0x1120 drivers/base/dd.c:899 bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427 __device_attach+0x593/0x8e0 drivers/base/dd.c:970 device_initial_probe+0x4a/0x60 drivers/base/dd.c:1017 bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487 device_add+0x1fff/0x26e0 drivers/base/core.c:3405 usb_set_configuration+0x37e9/0x3ed0 drivers/usb/core/message.c:2170 usb_generic_driver_probe+0x13c/0x300 drivers/usb/core/generic.c:238 usb_probe_device+0x309/0x570 drivers/usb/core/driver.c:293 really_probe+0x653/0x14b0 drivers/base/dd.c:596 __driver_probe_device+0x3e9/0x530 drivers/base/dd.c:752 driver_probe_device drivers/base/dd.c:782 [inline] __device_attach_driver+0x79f/0x1120 drivers/base/dd.c:899 bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427 __device_attach+0x593/0x8e0 drivers/base/dd.c:970 device_initial_probe+0x4a/0x60 drivers/base/dd.c:1017 bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487 device_add+0x1fff/0x26e0 drivers/base/core.c:3405 usb_new_device+0x1b8e/0x2950 drivers/usb/core/hub.c:2566 hub_port_connect drivers/usb/core/hub.c:5358 [inline] hub_port_connect_change drivers/usb/core/hub.c:5502 [inline] port_event drivers/usb/core/hub.c:5660 [inline] hub_event+0x58e3/0x89e0 drivers/usb/core/hub.c:5742 process_one_work+0xdb6/0x1820 kernel/workqueue.c:2307 worker_thread+0x10b3/0x21e0 kernel/workqueue.c:2454 kthread+0x3c7/0x500 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 Local variable mac created at: r871xu_drv_init+0x1771/0x3070 drivers/staging/rtl8712/usb_intf.c:394 usb_probe_interface+0xf19/0x1600 drivers/usb/core/driver.c:396 KMSAN: uninit-value in r871xu_drv_init https://syzkaller.appspot.com/bug?id=3cd92b1d85428b128503bfa7a250294c9ae00bd8Show less

In the Linux kernel, the following vulnerability has been resolved: nbd: fix io hung while disconnecting device In our tests, "qemu-nbd" triggers a io hung: INFO: task qemu-nbd:11445 blocked for more than 368 seconds. Not tainted 5.18.0-rc3-next-20220422-00003-g2176915513ca #884 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:qemu-nbd state:D stack: 0 pid:11445 ppid: 1 flags:0x00000000 Call Trace: <TASK> __schedule+0x480/0x1050 ? _raw_spin_lock_irqsave+0x3e/0xb0 schedule+0x9c/0x1b0 blk_mq_freeze_queue_wait+0x9d/0xf0 ? ipi_rseq+0x70/0x70 blk_mq_freeze_queue+0x2b/0x40 nbd_add_socket+0x6b/0x270 [nbd] nbd_ioctl+0x383/0x510 [nbd] blkdev_ioctl+0x18e/0x3e0 __x64_sys_ioctl+0xac/0x120 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd8ff706577 RSP: 002b:00007fd8fcdfebf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000040000000 RCX: 00007fd8ff706577 RDX: 000000000000000d RSI: 000000000000ab00 RDI: 000000000000000f RBP: 000000000000000f R08: 000000000000fbe8 R09: 000055fe497c62b0 R10: 00000002aff20000 R11: 0000000000000246 R12: 000000000000006d R13: 0000000000000000 R14: 00007ffe82dc5e70 R15: 00007fd8fcdff9c0 "qemu-ndb -d" will call ioctl 'NBD_DISCONNECT' first, however, following message was found: block nbd0: Send disconnect failed -32 Which indicate that something is wrong with the server. Then, "qemu-nbd -d" will call ioctl 'NBD_CLEAR_SOCK', however ioctl can't clear requests after commit 2516ab1543fd("nbd: only clear the queue on device teardown"). And in the meantime, request can't complete through timeout because nbd_xmit_timeout() will always return 'BLK_EH_RESET_TIMER', which means such request will never be completed in this situation. Now that the flag 'NBD_CMD_INFLIGHT' can make sure requests won't complete multiple times, switch back to call nbd_clear_sock() in nbd_clear_sock_ioctl(), so that inflight requests can be cleared.Show less