In the Linux kernel, the following vulnerability has been resolved: block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock blk_mq_{add,del}_queue_tag_set() functions add and remove queues from tagset, the functions make sure that tagset and queues are marked as shared when two or more queues are attached to the same tagset. Initially a tagset starts as unshared and when the number of added queues reaches two, blk_mq_add_queue_tag_set() marks it as shared along with all the queues attached to it. When the number of attached queues drops to 1 blk_mq_del_queue_tag_set() need to mark both the tagset and the remaining queues as unshared. Both functions need to freeze current queues in tagset before setting on unsetting BLK_MQ_F_TAG_QUEUE_SHARED flag. While doing so, both functions hold set->tag_list_lock mutex, which makes sense as we do not want queues to be added or deleted in the process. This used to work fine until commit 98d81f0df70c ("nvme: use blk_mq_[un]quiesce_tagset") made the nvme driver quiesce tagset instead of quiscing individual queues. blk_mq_quiesce_tagset() does the job and quiesce the queues in set->tag_list while holding set->tag_list_lock also. This results in deadlock between two threads with these stacktraces: __schedule+0x47c/0xbb0 ? timerqueue_add+0x66/0xb0 schedule+0x1c/0xa0 schedule_preempt_disabled+0xa/0x10 __mutex_lock.constprop.0+0x271/0x600 blk_mq_quiesce_tagset+0x25/0xc0 nvme_dev_disable+0x9c/0x250 nvme_timeout+0x1fc/0x520 blk_mq_handle_expired+0x5c/0x90 bt_iter+0x7e/0x90 blk_mq_queue_tag_busy_iter+0x27e/0x550 ? __blk_mq_complete_request_remote+0x10/0x10 ? __blk_mq_complete_request_remote+0x10/0x10 ? __call_rcu_common.constprop.0+0x1c0/0x210 blk_mq_timeout_work+0x12d/0x170 process_one_work+0x12e/0x2d0 worker_thread+0x288/0x3a0 ? rescuer_thread+0x480/0x480 kthread+0xb8/0xe0 ? kthread_park+0x80/0x80 ret_from_fork+0x2d/0x50 ? kthread_park+0x80/0x80 ret_from_fork_asm+0x11/0x20 __schedule+0x47c/0xbb0 ? xas_find+0x161/0x1a0 schedule+0x1c/0xa0 blk_mq_freeze_queue_wait+0x3d/0x70 ? destroy_sched_domains_rcu+0x30/0x30 blk_mq_update_tag_set_shared+0x44/0x80 blk_mq_exit_queue+0x141/0x150 del_gendisk+0x25a/0x2d0 nvme_ns_remove+0xc9/0x170 nvme_remove_namespaces+0xc7/0x100 nvme_remove+0x62/0x150 pci_device_remove+0x23/0x60 device_release_driver_internal+0x159/0x200 unbind_store+0x99/0xa0 kernfs_fop_write_iter+0x112/0x1e0 vfs_write+0x2b1/0x3d0 ksys_write+0x4e/0xb0 do_syscall_64+0x5b/0x160 entry_SYSCALL_64_after_hwframe+0x4b/0x53 The top stacktrace is showing nvme_timeout() called to handle nvme command timeout. timeout handler is trying to disable the controller and as a first step, it needs to blk_mq_quiesce_tagset() to tell blk-mq not to call queue callback handlers. The thread is stuck waiting for set->tag_list_lock as it tries to walk the queues in set->tag_list. The lock is held by the second thread in the bottom stack which is waiting for one of queues to be frozen. The queue usage counter will drop to zero after nvme_timeout() finishes, and this will not happen because the thread will wait for this mutex forever. Given that [un]quiescing queue is an operation that does not need to sleep, update blk_mq_[un]quiesce_tagset() to use RCU instead of taking set->tag_list_lock, update blk_mq_{add,del}_queue_tag_set() to use RCU safe list operations. Also, delete INIT_LIST_HEAD(&q->tag_set_list) in blk_mq_del_queue_tag_set() because we can not re-initialize it while the list is being traversed under RCU. The deleted queue will not be added/deleted to/from a tagset and it will be freed in blk_free_queue() after the end of RCU grace period.

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-1430 advisory.

    In the Linux kernel, the following vulnerability has been resolved:

    netfilter: nf_tables: reject duplicate device on updates (CVE-2025-38678)

    In the Linux kernel, the following vulnerability has been resolved:

    tcp_metrics: use dst_dev_net_rcu() (CVE-2025-40075)

    In the Linux kernel, the following vulnerability has been resolved:

    nfsd: fix refcount leak in nfsd_set_fh_dentry() (CVE-2025-40212)

    In the Linux kernel, the following vulnerability has been resolved:

    af_unix: Initialise scc_index in unix_add_edge(). (CVE-2025-40214)

    In the Linux kernel, the following vulnerability has been resolved:

    xfrm: delete x->tunnel as we delete x (CVE-2025-40215)

    In the Linux kernel, the following vulnerability has been resolved:

    vsock: Ignore signal/timeout on connect() if already established (CVE-2025-40248)

    In the Linux kernel, the following vulnerability has been resolved:

    net/mlx5: Clean up only new IRQ glue on request_irq() failure (CVE-2025-40250)

    In the Linux kernel, the following vulnerability has been resolved:

    devlink: rate: Unset parent pointer in devl_rate_nodes_destroy (CVE-2025-40251)

    In the Linux kernel, the following vulnerability has been resolved:

    net: openvswitch: remove never-working support for setting nsh fields (CVE-2025-40254)

    In the Linux kernel, the following vulnerability has been resolved:

    mptcp: fix a race in mptcp_pm_del_add_timer() (CVE-2025-40257)

    In the Linux kernel, the following vulnerability has been resolved:

    mptcp: fix race condition in mptcp_schedule_work() (CVE-2025-40258)

    In the Linux kernel, the following vulnerability has been resolved:

    scsi: sg: Do not sleep in atomic context (CVE-2025-40259)

    In the Linux kernel, the following vulnerability has been resolved:

    KVM: arm64: Check the untrusted offset in FF-A memory share (CVE-2025-40266)

    In the Linux kernel, the following vulnerability has been resolved:

    cifs: client: fix memory leak in smb3_fs_context_parse_param (CVE-2025-40268)

    In the Linux kernel, the following vulnerability has been resolved:

    fs/proc: fix uaf in proc_readdir_de() (CVE-2025-40271)

    In the Linux kernel, the following vulnerability has been resolved:

    mm/secretmem: fix use-after-free race in fault handler (CVE-2025-40272)

    In the Linux kernel, the following vulnerability has been resolved:

    NFSD: free copynotify stateid in nfs4_free_ol_stateid() (CVE-2025-40273)

    In the Linux kernel, the following vulnerability has been resolved:

    KVM: guest_memfd: Remove bindings on memslot deletion when gmem is dying (CVE-2025-40274)

    In the Linux kernel, the following vulnerability has been resolved:

    drm/vmwgfx: Validate command header size against SVGA_CMD_MAX_DATASIZE (CVE-2025-40277)

    In the Linux kernel, the following vulnerability has been resolved:

    net: sched: act_connmark: initialize struct tc_ife to fix kernel leak (CVE-2025-40279)

    In the Linux kernel, the following vulnerability has been resolved:

    sctp: prevent possible shift-out-of-bounds in sctp_transport_update_rto (CVE-2025-40281)

    In the Linux kernel, the following vulnerability has been resolved:

    exfat: fix improper check of dentry.stream.valid_size (CVE-2025-40287)

    In the Linux kernel, the following vulnerability has been resolved:

    crash: fix crashkernel resource shrink (CVE-2025-68198)

    In the Linux kernel, the following vulnerability has been resolved:

    codetag: debug: handle existing CODETAG_EMPTY in mark_objexts_empty for slabobj_ext (CVE-2025-68199)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf: Add bpf_prog_run_data_pointers() (CVE-2025-68200)

    In the Linux kernel, the following vulnerability has been resolved:

    sched_ext: Fix unsafe locking in the scx_dump_state() (CVE-2025-68202)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf: account for current allocated stack depth in widen_imprecise_scalars() (CVE-2025-68208)

    In the Linux kernel, the following vulnerability has been resolved:

    erofs: avoid infinite loop due to incomplete zstd-compressed data (CVE-2025-68210)

    In the Linux kernel, the following vulnerability has been resolved:

    timers: Fix NULL function pointer race in timer_shutdown_sync() (CVE-2025-68214)

    In the Linux kernel, the following vulnerability has been resolved:

    cifs: fix memory leak in smb3_fs_context_parse_param error path (CVE-2025-68219)

    In the Linux kernel, the following vulnerability has been resolved:

    smb: client: fix incomplete backport in cfids_invalidation_worker() (CVE-2025-68226)

    In the Linux kernel, the following vulnerability has been resolved:

    mptcp: Fix proto fallback detection with BPF (CVE-2025-68227)

    In the Linux kernel, the following vulnerability has been resolved:

    scsi: target: tcm_loop: Fix segfault in tcm_loop_tpg_address_show() (CVE-2025-68229)

    In the Linux kernel, the following vulnerability has been resolved:

    mm/mempool: fix poisoning order>0 pages with HIGHMEM (CVE-2025-68231)

    In the Linux kernel, the following vulnerability has been resolved:

    mtdchar: fix integer overflow in read/write ioctls (CVE-2025-68237)

    In the Linux kernel, the following vulnerability has been resolved:

    ipv4: route: Prevent rt_bind_exception() from rebinding stale fnhe (CVE-2025-68241)

    In the Linux kernel, the following vulnerability has been resolved:

    NFS: Fix LTP test failures when timestamps are delegated (CVE-2025-68242)

    In the Linux kernel, the following vulnerability has been resolved:

    drm/i915: Avoid lock inversion when pinning to GGTT on CHV/BXT+VTD (CVE-2025-68244)

    In the Linux kernel, the following vulnerability has been resolved:

    KVM: SVM: Don't skip unrelated instruction if INT3/INTO is replaced (CVE-2025-68259)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: add i_data_sem protection in ext4_destroy_inline_data_nolock() (CVE-2025-68261)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: refresh inline data size before write operations (CVE-2025-68264)

    In the Linux kernel, the following vulnerability has been resolved:

    nvme: fix admin request_queue lifetime (CVE-2025-68265)

    In the Linux kernel, the following vulnerability has been resolved:

    libceph: replace BUG_ON with bounds check for map->max_osd (CVE-2025-68283)

    In the Linux kernel, the following vulnerability has been resolved:

    libceph: prevent potential out-of-bounds writes in handle_auth_session_key() (CVE-2025-68284)

    In the Linux kernel, the following vulnerability has been resolved:

    libceph: fix potential use-after-free in have_mon_and_osd_map() (CVE-2025-68285)

    In the Linux kernel, the following vulnerability has been resolved:

    usb: storage: Fix memory leak in USB bulk transport (CVE-2025-68288)

    In the Linux kernel, the following vulnerability has been resolved:

    mm/memfd: fix information leak in hugetlb folios (CVE-2025-68292)

    In the Linux kernel, the following vulnerability has been resolved:

    mm/huge_memory: fix NULL pointer deference when splitting folio (CVE-2025-68293)

    In the Linux kernel, the following vulnerability has been resolved:

    smb: client: fix memory leak in cifs_construct_tcon() (CVE-2025-68295)

    In the Linux kernel, the following vulnerability has been resolved:

    drm, fbcon, vga_switcheroo: Avoid race condition in fbcon setup (CVE-2025-68296)

    In the Linux kernel, the following vulnerability has been resolved:

    ceph: fix crash in process_v2_sparse_read() for encrypted directories (CVE-2025-68297)

    In the Linux kernel, the following vulnerability has been resolved:

    net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop (CVE-2025-68325)

    In the Linux kernel, the following vulnerability has been resolved:

    tracing: Fix WARN_ON in tracing_buffers_mmap_close for split VMAs (CVE-2025-68329)

    In the Linux kernel, the following vulnerability has been resolved:

    usb: uas: fix urb unmapping issue when the uas device is remove during ongoing data transfer     (CVE-2025-68331)

    In the Linux kernel, the following vulnerability has been resolved:

    jbd2: avoid bug_on in jbd2_journal_get_create_access() when file system corrupted (CVE-2025-68337)

    In the Linux kernel, the following vulnerability has been resolved:

    team: Move team device type change at the end of team_port_add (CVE-2025-68340)

    In the Linux kernel, the following vulnerability has been resolved:

    veth: reduce XDP no_direct return section to fix race (CVE-2025-68341)

    In the Linux kernel, the following vulnerability has been resolved:

    block: fix memory leak in __blkdev_issue_zero_pages (CVE-2025-68348)

    In the Linux kernel, the following vulnerability has been resolved:

    NFSv4/pNFS: Clear NFS_INO_LAYOUTCOMMIT in pnfs_mark_layout_stateid_invalid (CVE-2025-68349)

    In the Linux kernel, the following vulnerability has been resolved:

    erofs: limit the level of fs stacking for file-backed mounts (CVE-2025-68361)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf: Check skb->transport_header is set in bpf_skb_check_mtu (CVE-2025-68363)

    In the Linux kernel, the following vulnerability has been resolved:

    nbd: defer config unlock in nbd_genl_connect (CVE-2025-68366)

    In the Linux kernel, the following vulnerability has been resolved:

    ntfs3: init run lock for extend inode (CVE-2025-68369)

    In the Linux kernel, the following vulnerability has been resolved:

    scsi: smartpqi: Fix device resources accessed after device removal (CVE-2025-68371)

    In the Linux kernel, the following vulnerability has been resolved:

    nbd: defer config put in recv_work (CVE-2025-68372)

    In the Linux kernel, the following vulnerability has been resolved:

    md: fix rcu protection in md_wakeup_thread (CVE-2025-68374)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf: Fix stackmap overflow check in __bpf_get_stackid() (CVE-2025-68378)

    In the Linux kernel, the following vulnerability has been resolved:

    crypto: asymmetric_keys - prevent overflow in asymmetric_key_generate_id (CVE-2025-68724)

    In the Linux kernel, the following vulnerability has been resolved:

    ntfs3: Fix uninit buffer allocated by __getname() (CVE-2025-68727)

    In the Linux kernel, the following vulnerability has been resolved:

    ntfs3: fix uninit memory after failed mi_read in mi_format_new (CVE-2025-68728)

    In the Linux kernel, the following vulnerability has been resolved:

    ima: Handle error code returned by ima_filter_rule_match() (CVE-2025-68740)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf: Fix invalid prog->stats access when update_effective_progs fails (CVE-2025-68742)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf: Free special fields when update [lru_,]percpu_hash maps (CVE-2025-68744)

    In the Linux kernel, the following vulnerability has been resolved:

    spi: tegra210-quad: Fix timeout handling (CVE-2025-68746)

    In the Linux kernel, the following vulnerability has been resolved:

    block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock (CVE-2025-68756)

    In the Linux kernel, the following vulnerability has been resolved:

    NFS: Automounted filesystems should inherit ro,noexec,nodev,sync flags (CVE-2025-68764)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock     blk_mq_{add,del}_queue_tag_set() functions add and remove queues from tagset, the functions make sure that     tagset and queues are marked as shared when two or more queues are attached to the same tagset. Initially     a tagset starts as unshared and when the number of added queues reaches two, blk_mq_add_queue_tag_set()     marks it as shared along with all the queues attached to it. When the number of attached queues drops to 1     blk_mq_del_queue_tag_set() need to mark both the tagset and the remaining queues as unshared. Both     functions need to freeze current queues in tagset before setting on unsetting BLK_MQ_F_TAG_QUEUE_SHARED     flag. While doing so, both functions hold set->tag_list_lock mutex, which makes sense as we do not want     queues to be added or deleted in the process. This used to work fine until commit 98d81f0df70c (nvme: use     blk_mq_[un]quiesce_tagset) made the nvme driver quiesce tagset instead of quiscing individual queues.
    blk_mq_quiesce_tagset() does the job and quiesce the queues in set->tag_list while holding     set->tag_list_lock also. This results in deadlock between two threads with these stacktraces:
    __schedule+0x47c/0xbb0 ? timerqueue_add+0x66/0xb0 schedule+0x1c/0xa0 schedule_preempt_disabled+0xa/0x10
    __mutex_lock.constprop.0+0x271/0x600 blk_mq_quiesce_tagset+0x25/0xc0 nvme_dev_disable+0x9c/0x250     nvme_timeout+0x1fc/0x520 blk_mq_handle_expired+0x5c/0x90 bt_iter+0x7e/0x90     blk_mq_queue_tag_busy_iter+0x27e/0x550 ? __blk_mq_complete_request_remote+0x10/0x10 ?
    __blk_mq_complete_request_remote+0x10/0x10 ? __call_rcu_common.constprop.0+0x1c0/0x210     blk_mq_timeout_work+0x12d/0x170 process_one_work+0x12e/0x2d0 worker_thread+0x288/0x3a0 ?     rescuer_thread+0x480/0x480 kthread+0xb8/0xe0 ? kthread_park+0x80/0x80 ret_from_fork+0x2d/0x50 ?     kthread_park+0x80/0x80 ret_from_fork_asm+0x11/0x20 __schedule+0x47c/0xbb0 ? xas_find+0x161/0x1a0     schedule+0x1c/0xa0 blk_mq_freeze_queue_wait+0x3d/0x70 ? destroy_sched_domains_rcu+0x30/0x30     blk_mq_update_tag_set_shared+0x44/0x80 blk_mq_exit_queue+0x141/0x150 del_gendisk+0x25a/0x2d0     nvme_ns_remove+0xc9/0x170 nvme_remove_namespaces+0xc7/0x100 nvme_remove+0x62/0x150     pci_device_remove+0x23/0x60 device_release_driver_internal+0x159/0x200 unbind_store+0x99/0xa0     kernfs_fop_write_iter+0x112/0x1e0 vfs_write+0x2b1/0x3d0 ksys_write+0x4e/0xb0 do_syscall_64+0x5b/0x160     entry_SYSCALL_64_after_hwframe+0x4b/0x53 The top stacktrace is showing nvme_timeout() called to handle     nvme command timeout. timeout handler is trying to disable the controller and as a first step, it needs to     blk_mq_quiesce_tagset() to tell blk-mq not to call queue callback handlers. The thread is stuck waiting     for set->tag_list_lock as it tries to walk the queues in set->tag_list. The lock is held by the second     thread in the bottom stack which is waiting for one of queues to be frozen. The queue usage counter will     drop to zero after nvme_timeout() finishes, and this will not happen because the thread will wait for this     mutex forever. Given that [un]quiescing queue is an operation that does not need to sleep, update     blk_mq_[un]quiesce_tagset() to use RCU instead of taking set->tag_list_lock, update     blk_mq_{add,del}_queue_tag_set() to use RCU safe list operations. Also, delete     INIT_LIST_HEAD(&q->tag_set_list) in blk_mq_del_queue_tag_set() because we can not re-initialize it while     the list is being traversed under RCU. The deleted queue will not be added/deleted to/from a tagset and it     will be freed in blk_free_queue() after the end of RCU grace period. (CVE-2025-68756)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Severity
299530	Amazon Linux 2023 : bpftool6.12, kernel6.12, kernel6.12-devel (ALAS2023-2026-1430)	Nessus	Amazon Linux Local Security Checks	medium
281754	Linux Distros Unpatched Vulnerability : CVE-2025-68756	Nessus	Misc.	high

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