Total
310284 CVE
CVE | Vendors | Products | Updated | CVSS v3.1 |
---|---|---|---|---|
CVE-2023-53206 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus_core) Fix NULL pointer dereference Pass i2c_client to _pmbus_is_enabled to drop the assumption that a regulator device is passed in. This will fix the issue of a NULL pointer dereference when called from _pmbus_get_flags. | ||||
CVE-2023-53210 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: md/raid5-cache: fix null-ptr-deref for r5l_flush_stripe_to_raid() r5l_flush_stripe_to_raid() will check if the list 'flushing_ios' is empty, and then submit 'flush_bio', however, r5l_log_flush_endio() is clearing the list first and then clear the bio, which will cause null-ptr-deref: T1: submit flush io raid5d handle_active_stripes r5l_flush_stripe_to_raid // list is empty // add 'io_end_ios' to the list bio_init submit_bio // io1 T2: io1 is done r5l_log_flush_endio list_splice_tail_init // clear the list T3: submit new flush io ... r5l_flush_stripe_to_raid // list is empty // add 'io_end_ios' to the list bio_init bio_uninit // clear bio->bi_blkg submit_bio // null-ptr-deref Fix this problem by clearing bio before clearing the list in r5l_log_flush_endio(). | ||||
CVE-2022-50295 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: io_uring/msg_ring: Fix NULL pointer dereference in io_msg_send_fd() Syzkaller produced the below call trace: BUG: KASAN: null-ptr-deref in io_msg_ring+0x3cb/0x9f0 Write of size 8 at addr 0000000000000070 by task repro/16399 CPU: 0 PID: 16399 Comm: repro Not tainted 6.1.0-rc1 #28 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 Call Trace: <TASK> dump_stack_lvl+0xcd/0x134 ? io_msg_ring+0x3cb/0x9f0 kasan_report+0xbc/0xf0 ? io_msg_ring+0x3cb/0x9f0 kasan_check_range+0x140/0x190 io_msg_ring+0x3cb/0x9f0 ? io_msg_ring_prep+0x300/0x300 io_issue_sqe+0x698/0xca0 io_submit_sqes+0x92f/0x1c30 __do_sys_io_uring_enter+0xae4/0x24b0 .... RIP: 0033:0x7f2eaf8f8289 RSP: 002b:00007fff40939718 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2eaf8f8289 RDX: 0000000000000000 RSI: 0000000000006f71 RDI: 0000000000000004 RBP: 00007fff409397a0 R08: 0000000000000000 R09: 0000000000000039 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004006d0 R13: 00007fff40939880 R14: 0000000000000000 R15: 0000000000000000 </TASK> Kernel panic - not syncing: panic_on_warn set ... We don't have a NULL check on file_ptr in io_msg_send_fd() function, so when file_ptr is NUL src_file is also NULL and get_file() dereferences a NULL pointer and leads to above crash. Add a NULL check to fix this issue. | ||||
CVE-2023-53225 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: spi: imx: Don't skip cleanup in remove's error path Returning early in a platform driver's remove callback is wrong. In this case the dma resources are not released in the error path. this is never retried later and so this is a permanent leak. To fix this, only skip hardware disabling if waking the device fails. | ||||
CVE-2022-50303 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Fix double release compute pasid If kfd_process_device_init_vm returns failure after vm is converted to compute vm and vm->pasid set to compute pasid, KFD will not take pdd->drm_file reference. As a result, drm close file handler maybe called to release the compute pasid before KFD process destroy worker to release the same pasid and set vm->pasid to zero, this generates below WARNING backtrace and NULL pointer access. Add helper amdgpu_amdkfd_gpuvm_set_vm_pasid and call it at the last step of kfd_process_device_init_vm, to ensure vm pasid is the original pasid if acquiring vm failed or is the compute pasid with pdd->drm_file reference taken to avoid double release same pasid. amdgpu: Failed to create process VM object ida_free called for id=32770 which is not allocated. WARNING: CPU: 57 PID: 72542 at ../lib/idr.c:522 ida_free+0x96/0x140 RIP: 0010:ida_free+0x96/0x140 Call Trace: amdgpu_pasid_free_delayed+0xe1/0x2a0 [amdgpu] amdgpu_driver_postclose_kms+0x2d8/0x340 [amdgpu] drm_file_free.part.13+0x216/0x270 [drm] drm_close_helper.isra.14+0x60/0x70 [drm] drm_release+0x6e/0xf0 [drm] __fput+0xcc/0x280 ____fput+0xe/0x20 task_work_run+0x96/0xc0 do_exit+0x3d0/0xc10 BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:ida_free+0x76/0x140 Call Trace: amdgpu_pasid_free_delayed+0xe1/0x2a0 [amdgpu] amdgpu_driver_postclose_kms+0x2d8/0x340 [amdgpu] drm_file_free.part.13+0x216/0x270 [drm] drm_close_helper.isra.14+0x60/0x70 [drm] drm_release+0x6e/0xf0 [drm] __fput+0xcc/0x280 ____fput+0xe/0x20 task_work_run+0x96/0xc0 do_exit+0x3d0/0xc10 | ||||
CVE-2022-50288 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: qlcnic: prevent ->dcb use-after-free on qlcnic_dcb_enable() failure adapter->dcb would get silently freed inside qlcnic_dcb_enable() in case qlcnic_dcb_attach() would return an error, which always happens under OOM conditions. This would lead to use-after-free because both of the existing callers invoke qlcnic_dcb_get_info() on the obtained pointer, which is potentially freed at that point. Propagate errors from qlcnic_dcb_enable(), and instead free the dcb pointer at callsite using qlcnic_dcb_free(). This also removes the now unused qlcnic_clear_dcb_ops() helper, which was a simple wrapper around kfree() also causing memory leaks for partially initialized dcb. Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool. | ||||
CVE-2022-50273 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to do sanity check on destination blkaddr during recovery As Wenqing Liu reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216456 loop5: detected capacity change from 0 to 131072 F2FS-fs (loop5): recover_inode: ino = 6, name = hln, inline = 1 F2FS-fs (loop5): recover_data: ino = 6 (i_size: recover) err = 0 F2FS-fs (loop5): recover_inode: ino = 6, name = hln, inline = 1 F2FS-fs (loop5): recover_data: ino = 6 (i_size: recover) err = 0 F2FS-fs (loop5): recover_inode: ino = 6, name = hln, inline = 1 F2FS-fs (loop5): recover_data: ino = 6 (i_size: recover) err = 0 F2FS-fs (loop5): Bitmap was wrongly set, blk:5634 ------------[ cut here ]------------ WARNING: CPU: 3 PID: 1013 at fs/f2fs/segment.c:2198 RIP: 0010:update_sit_entry+0xa55/0x10b0 [f2fs] Call Trace: <TASK> f2fs_do_replace_block+0xa98/0x1890 [f2fs] f2fs_replace_block+0xeb/0x180 [f2fs] recover_data+0x1a69/0x6ae0 [f2fs] f2fs_recover_fsync_data+0x120d/0x1fc0 [f2fs] f2fs_fill_super+0x4665/0x61e0 [f2fs] mount_bdev+0x2cf/0x3b0 legacy_get_tree+0xed/0x1d0 vfs_get_tree+0x81/0x2b0 path_mount+0x47e/0x19d0 do_mount+0xce/0xf0 __x64_sys_mount+0x12c/0x1a0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd If we enable CONFIG_F2FS_CHECK_FS config, it will trigger a kernel panic instead of warning. The root cause is: in fuzzed image, SIT table is inconsistent with inode mapping table, result in triggering such warning during SIT table update. This patch introduces a new flag DATA_GENERIC_ENHANCE_UPDATE, w/ this flag, data block recovery flow can check destination blkaddr's validation in SIT table, and skip f2fs_replace_block() to avoid inconsistent status. | ||||
CVE-2023-53248 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: install stub fence into potential unused fence pointers When using cpu to update page tables, vm update fences are unused. Install stub fence into these fence pointers instead of NULL to avoid NULL dereference when calling dma_fence_wait() on them. | ||||
CVE-2022-50272 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer() Wei Chen reports a kernel bug as blew: general protection fault, probably for non-canonical address KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] ... Call Trace: <TASK> __i2c_transfer+0x77e/0x1930 drivers/i2c/i2c-core-base.c:2109 i2c_transfer+0x1d5/0x3d0 drivers/i2c/i2c-core-base.c:2170 i2cdev_ioctl_rdwr+0x393/0x660 drivers/i2c/i2c-dev.c:297 i2cdev_ioctl+0x75d/0x9f0 drivers/i2c/i2c-dev.c:458 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd834a8bded In az6027_i2c_xfer(), if msg[i].addr is 0x99, a null-ptr-deref will caused when accessing msg[i].buf. For msg[i].len is 0 and msg[i].buf is null. Fix this by checking msg[i].len in az6027_i2c_xfer(). | ||||
CVE-2022-50276 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: power: supply: fix null pointer dereferencing in power_supply_get_battery_info when kmalloc() fail to allocate memory in kasprintf(), propname will be NULL, strcmp() called by of_get_property() will cause null pointer dereference. So return ENOMEM if kasprintf() return NULL pointer. | ||||
CVE-2023-53207 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: ublk: fail to recover device if queue setup is interrupted In ublk_ctrl_end_recovery(), if wait_for_completion_interruptible() is interrupted by signal, queues aren't setup successfully yet, so we have to fail UBLK_CMD_END_USER_RECOVERY, otherwise kernel oops can be triggered. | ||||
CVE-2023-53230 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix warning in cifs_smb3_do_mount() This fixes the following warning reported by kernel test robot fs/smb/client/cifsfs.c:982 cifs_smb3_do_mount() warn: possible memory leak of 'cifs_sb' | ||||
CVE-2023-53227 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
This CVE ID has been rejected or withdrawn by its CVE Numbering Authority. | ||||
CVE-2023-53208 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: KVM: nSVM: Load L1's TSC multiplier based on L1 state, not L2 state When emulating nested VM-Exit, load L1's TSC multiplier if L1's desired ratio doesn't match the current ratio, not if the ratio L1 is using for L2 diverges from the default. Functionally, the end result is the same as KVM will run L2 with L1's multiplier if L2's multiplier is the default, i.e. checking that L1's multiplier is loaded is equivalent to checking if L2 has a non-default multiplier. However, the assertion that TSC scaling is exposed to L1 is flawed, as userspace can trigger the WARN at will by writing the MSR and then updating guest CPUID to hide the feature (modifying guest CPUID is allowed anytime before KVM_RUN). E.g. hacking KVM's state_test selftest to do vcpu_set_msr(vcpu, MSR_AMD64_TSC_RATIO, 0); vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_TSCRATEMSR); after restoring state in a new VM+vCPU yields an endless supply of: ------------[ cut here ]------------ WARNING: CPU: 10 PID: 206939 at arch/x86/kvm/svm/nested.c:1105 nested_svm_vmexit+0x6af/0x720 [kvm_amd] Call Trace: nested_svm_exit_handled+0x102/0x1f0 [kvm_amd] svm_handle_exit+0xb9/0x180 [kvm_amd] kvm_arch_vcpu_ioctl_run+0x1eab/0x2570 [kvm] kvm_vcpu_ioctl+0x4c9/0x5b0 [kvm] ? trace_hardirqs_off+0x4d/0xa0 __se_sys_ioctl+0x7a/0xc0 __x64_sys_ioctl+0x21/0x30 do_syscall_64+0x41/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Unlike the nested VMRUN path, hoisting the svm->tsc_scaling_enabled check into the if-statement is wrong as KVM needs to ensure L1's multiplier is loaded in the above scenario. Alternatively, the WARN_ON() could simply be deleted, but that would make KVM's behavior even more subtle, e.g. it's not immediately obvious why it's safe to write MSR_AMD64_TSC_RATIO when checking only tsc_ratio_msr. | ||||
CVE-2022-50275 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: drm/radeon: Add the missed acpi_put_table() to fix memory leak When the radeon driver reads the bios information from ACPI table in radeon_acpi_vfct_bios(), it misses to call acpi_put_table() to release the ACPI memory after the init, so add acpi_put_table() properly to fix the memory leak. v2: fix text formatting (Alex) | ||||
CVE-2022-50270 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix the assign logic of iocb commit 18ae8d12991b ("f2fs: show more DIO information in tracepoint") introduces iocb field in 'f2fs_direct_IO_enter' trace event And it only assigns the pointer and later it accesses its field in trace print log. Unable to handle kernel paging request at virtual address ffffffc04cef3d30 Mem abort info: ESR = 0x96000007 EC = 0x25: DABT (current EL), IL = 32 bits pc : trace_raw_output_f2fs_direct_IO_enter+0x54/0xa4 lr : trace_raw_output_f2fs_direct_IO_enter+0x2c/0xa4 sp : ffffffc0443cbbd0 x29: ffffffc0443cbbf0 x28: ffffff8935b120d0 x27: ffffff8935b12108 x26: ffffff8935b120f0 x25: ffffff8935b12100 x24: ffffff8935b110c0 x23: ffffff8935b10000 x22: ffffff88859a936c x21: ffffff88859a936c x20: ffffff8935b110c0 x19: ffffff8935b10000 x18: ffffffc03b195060 x17: ffffff8935b11e76 x16: 00000000000000cc x15: ffffffef855c4f2c x14: 0000000000000001 x13: 000000000000004e x12: ffff0000ffffff00 x11: ffffffef86c350d0 x10: 00000000000010c0 x9 : 000000000fe0002c x8 : ffffffc04cef3d28 x7 : 7f7f7f7f7f7f7f7f x6 : 0000000002000000 x5 : ffffff8935b11e9a x4 : 0000000000006250 x3 : ffff0a00ffffff04 x2 : 0000000000000002 x1 : ffffffef86a0a31f x0 : ffffff8935b10000 Call trace: trace_raw_output_f2fs_direct_IO_enter+0x54/0xa4 print_trace_fmt+0x9c/0x138 print_trace_line+0x154/0x254 tracing_read_pipe+0x21c/0x380 vfs_read+0x108/0x3ac ksys_read+0x7c/0xec __arm64_sys_read+0x20/0x30 invoke_syscall+0x60/0x150 el0_svc_common.llvm.1237943816091755067+0xb8/0xf8 do_el0_svc+0x28/0xa0 Fix it by copying the required variables for printing and while at it fix the similar issue at some other places in the same file. | ||||
CVE-2023-53246 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 5.5 Medium |
In the Linux kernel, the following vulnerability has been resolved: cifs: fix DFS traversal oops without CONFIG_CIFS_DFS_UPCALL When compiled with CONFIG_CIFS_DFS_UPCALL disabled, cifs_dfs_d_automount is NULL. cifs.ko logic for mapping CIFS_FATTR_DFS_REFERRAL attributes to S_AUTOMOUNT and corresponding dentry flags is retained regardless of CONFIG_CIFS_DFS_UPCALL, leading to a NULL pointer dereference in VFS follow_automount() when traversing a DFS referral link: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: <TASK> __traverse_mounts+0xb5/0x220 ? cifs_revalidate_mapping+0x65/0xc0 [cifs] step_into+0x195/0x610 ? lookup_fast+0xe2/0xf0 path_lookupat+0x64/0x140 filename_lookup+0xc2/0x140 ? __create_object+0x299/0x380 ? kmem_cache_alloc+0x119/0x220 ? user_path_at_empty+0x31/0x50 user_path_at_empty+0x31/0x50 __x64_sys_chdir+0x2a/0xd0 ? exit_to_user_mode_prepare+0xca/0x100 do_syscall_64+0x42/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc This fix adds an inline cifs_dfs_d_automount() {return -EREMOTE} handler when CONFIG_CIFS_DFS_UPCALL is disabled. An alternative would be to avoid flagging S_AUTOMOUNT, etc. without CONFIG_CIFS_DFS_UPCALL. This approach was chosen as it provides more control over the error path. | ||||
CVE-2023-53203 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7996: rely on mt76_connac2_mac_tx_rate_val In order to fix a possible NULL pointer dereference in mt7996_mac_write_txwi() of vif pointer, export mt76_connac2_mac_tx_rate_val utility routine and reuse it in mt7996 driver. | ||||
CVE-2022-50315 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: ata: ahci: Match EM_MAX_SLOTS with SATA_PMP_MAX_PORTS UBSAN complains about array-index-out-of-bounds: [ 1.980703] kernel: UBSAN: array-index-out-of-bounds in /build/linux-9H675w/linux-5.15.0/drivers/ata/libahci.c:968:41 [ 1.980709] kernel: index 15 is out of range for type 'ahci_em_priv [8]' [ 1.980713] kernel: CPU: 0 PID: 209 Comm: scsi_eh_8 Not tainted 5.15.0-25-generic #25-Ubuntu [ 1.980716] kernel: Hardware name: System manufacturer System Product Name/P5Q3, BIOS 1102 06/11/2010 [ 1.980718] kernel: Call Trace: [ 1.980721] kernel: <TASK> [ 1.980723] kernel: show_stack+0x52/0x58 [ 1.980729] kernel: dump_stack_lvl+0x4a/0x5f [ 1.980734] kernel: dump_stack+0x10/0x12 [ 1.980736] kernel: ubsan_epilogue+0x9/0x45 [ 1.980739] kernel: __ubsan_handle_out_of_bounds.cold+0x44/0x49 [ 1.980742] kernel: ahci_qc_issue+0x166/0x170 [libahci] [ 1.980748] kernel: ata_qc_issue+0x135/0x240 [ 1.980752] kernel: ata_exec_internal_sg+0x2c4/0x580 [ 1.980754] kernel: ? vprintk_default+0x1d/0x20 [ 1.980759] kernel: ata_exec_internal+0x67/0xa0 [ 1.980762] kernel: sata_pmp_read+0x8d/0xc0 [ 1.980765] kernel: sata_pmp_read_gscr+0x3c/0x90 [ 1.980768] kernel: sata_pmp_attach+0x8b/0x310 [ 1.980771] kernel: ata_eh_revalidate_and_attach+0x28c/0x4b0 [ 1.980775] kernel: ata_eh_recover+0x6b6/0xb30 [ 1.980778] kernel: ? ahci_do_hardreset+0x180/0x180 [libahci] [ 1.980783] kernel: ? ahci_stop_engine+0xb0/0xb0 [libahci] [ 1.980787] kernel: ? ahci_do_softreset+0x290/0x290 [libahci] [ 1.980792] kernel: ? trace_event_raw_event_ata_eh_link_autopsy_qc+0xe0/0xe0 [ 1.980795] kernel: sata_pmp_eh_recover.isra.0+0x214/0x560 [ 1.980799] kernel: sata_pmp_error_handler+0x23/0x40 [ 1.980802] kernel: ahci_error_handler+0x43/0x80 [libahci] [ 1.980806] kernel: ata_scsi_port_error_handler+0x2b1/0x600 [ 1.980810] kernel: ata_scsi_error+0x9c/0xd0 [ 1.980813] kernel: scsi_error_handler+0xa1/0x180 [ 1.980817] kernel: ? scsi_unjam_host+0x1c0/0x1c0 [ 1.980820] kernel: kthread+0x12a/0x150 [ 1.980823] kernel: ? set_kthread_struct+0x50/0x50 [ 1.980826] kernel: ret_from_fork+0x22/0x30 [ 1.980831] kernel: </TASK> This happens because sata_pmp_init_links() initialize link->pmp up to SATA_PMP_MAX_PORTS while em_priv is declared as 8 elements array. I can't find the maximum Enclosure Management ports specified in AHCI spec v1.3.1, but "12.2.1 LED message type" states that "Port Multiplier Information" can utilize 4 bits, which implies it can support up to 16 ports. Hence, use SATA_PMP_MAX_PORTS as EM_MAX_SLOTS to resolve the issue. BugLink: https://bugs.launchpad.net/bugs/1970074 | ||||
CVE-2022-50314 | 1 Linux | 1 Linux Kernel | 2025-09-17 | 7.0 High |
In the Linux kernel, the following vulnerability has been resolved: nbd: Fix hung when signal interrupts nbd_start_device_ioctl() syzbot reported hung task [1]. The following program is a simplified version of the reproducer: int main(void) { int sv[2], fd; if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv) < 0) return 1; if ((fd = open("/dev/nbd0", 0)) < 0) return 1; if (ioctl(fd, NBD_SET_SIZE_BLOCKS, 0x81) < 0) return 1; if (ioctl(fd, NBD_SET_SOCK, sv[0]) < 0) return 1; if (ioctl(fd, NBD_DO_IT) < 0) return 1; return 0; } When signal interrupt nbd_start_device_ioctl() waiting the condition atomic_read(&config->recv_threads) == 0, the task can hung because it waits the completion of the inflight IOs. This patch fixes the issue by clearing queue, not just shutdown, when signal interrupt nbd_start_device_ioctl(). |