{
  "cveId": "CVE-2026-23018",
  "url": "https://patchblox.com/security/cve/CVE-2026-23018",
  "summary": "CVE-2026-23018 is fixed in 14 products on 1 platform, first by DEBIAN-CVE-2026-23018, released January 31, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  btrfs: release path before initializing extent t...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  btrfs: release path before initializing extent tree in btrfs_read_locked_inode()  In btrfs_read_locked_inode() we are calling btrfs_init_file_extent_tree() while holding a path with a read locked leaf from a subvolume tree, and btrfs_init_file_extent_tree() may do a GFP_KERNEL allocation, which can trigger reclaim.  This can create a circular lock dependency which lockdep warns about with the following splat:     [6.1433] ======================================================    [6.1574] WARNING: possible circular locking dependency detected    [6.1583] 6.18.0\u002B #4 Tainted: G     U    [6.1591] ------------------------------------------------------    [6.1599] kswapd0/117 is trying to acquire lock:    [6.1606] ffff8d9b6333c5b8 (\u0026delayed_node-\u003Emutex){\u002B.\u002B.}-{3:3}, at: __btrfs_release_delayed_node.part.0\u002B0x39/0x2f0    [6.1625]             but task is already holding lock:    [6.1633] ffffffffa4ab8ce0 (fs_reclaim){\u002B.\u002B.}-{0:0}, at: balance_pgdat\u002B0x195/0xc60    [6.1646]             which lock already depends on the new lock.     [6.1657]             the existing dependency chain (in reverse order) is:    [6.1667]             -\u003E #2 (fs_reclaim){\u002B.\u002B.}-{0:0}:    [6.1677]        fs_reclaim_acquire\u002B0x9d/0xd0    [6.1685]        __kmalloc_cache_noprof\u002B0x59/0x750    [6.1694]        btrfs_init_file_extent_tree\u002B0x90/0x100    [6.1702]        btrfs_read_locked_inode\u002B0xc3/0x6b0    [6.1710]        btrfs_iget\u002B0xbb/0xf0    [6.1716]        btrfs_lookup_dentry\u002B0x3c5/0x8e0    [6.1724]        btrfs_lookup\u002B0x12/0x30    [6.1731]        lookup_open.isra.0\u002B0x1aa/0x6a0    [6.1739]        path_openat\u002B0x5f7/0xc60    [6.1746]        do_filp_open\u002B0xd6/0x180    [6.1753]        do_sys_openat2\u002B0x8b/0xe0    [6.1760]        __x64_sys_openat\u002B0x54/0xa0    [6.1768]        do_syscall_64\u002B0x97/0x3e0    [6.1776]        entry_SYSCALL_64_after_hwframe\u002B0x76/0x7e    [6.1784]             -\u003E #1 (btrfs-tree-00){\u002B\u002B\u002B\u002B}-{3:3}:    [6.1794]        lock_release\u002B0x127/0x2a0    [6.1801]        up_read\u002B0x1b/0x30    [6.1808]        btrfs_search_slot\u002B0x8e0/0xff0    [6.1817]        btrfs_lookup_inode\u002B0x52/0xd0    [6.1825]        __btrfs_update_delayed_inode\u002B0x73/0x520    [6.1833]        btrfs_commit_inode_delayed_inode\u002B0x11a/0x120    [6.1842]        btrfs_log_inode\u002B0x608/0x1aa0    [6.1849]        btrfs_log_inode_parent\u002B0x249/0xf80    [6.1857]        btrfs_log_dentry_safe\u002B0x3e/0x60    [6.1865]        btrfs_sync_file\u002B0x431/0x690    [6.1872]        do_fsync\u002B0x39/0x80    [6.1879]        __x64_sys_fsync\u002B0x13/0x20    [6.1887]        do_syscall_64\u002B0x97/0x3e0    [6.1894]        entry_SYSCALL_64_after_hwframe\u002B0x76/0x7e    [6.1903]             -\u003E #0 (\u0026delayed_node-\u003Emutex){\u002B.\u002B.}-{3:3}:    [6.1913]        __lock_acquire\u002B0x15e9/0x2820    [6.1920]        lock_acquire\u002B0xc9/0x2d0    [6.1927]        __mutex_lock\u002B0xcc/0x10a0    [6.1934]        __btrfs_release_delayed_node.part.0\u002B0x39/0x2f0    [6.1944]        btrfs_evict_inode\u002B0x20b/0x4b0    [6.1952]        evict\u002B0x15a/0x2f0    [6.1958]        prune_icache_sb\u002B0x91/0xd0    [6.1966]        super_cache_scan\u002B0x150/0x1d0    [6.1974]        do_shrink_slab\u002B0x155/0x6f0    [6.1981]        shrink_slab\u002B0x48e/0x890    [6.1988]        shrink_one\u002B0x11a/0x1f0    [6.1995]        shrink_node\u002B0xbfd/0x1320    [6.1002]        balance_pgdat\u002B0x67f/0xc60    [6.1321]        kswapd\u002B0x1dc/0x3e0    [6.1643]        kthread\u002B0xff/0x240    [6.1965]        ret_from_fork\u002B0x223/0x280    [6.1287]        ret_from_fork_asm\u002B0x1a/0x30    [6.1616]             other info that might help us debug this:     [6.1561] Chain exists of:               \u0026delayed_node-\u003Emutex --\u003E btrfs-tree-00 --\u003E fs_reclaim     [6.1503]  Possible unsafe locking scenario:     [6.1110]        CPU0                    CPU1    [6.1411]        ----                    ----    [6.1707]   lock(fs_reclaim);    [6.1998]                                lock(btrfs-tree-00);    [6.1291]                                lock(fs_reclaim);    [6.1581]   lock(\u0026del ---truncated---",
  "published": "2026-01-31T12:16:05Z",
  "severity": "medium",
  "cvss": 5.5,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.0012,
  "epssPercentile": 0.01856,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "dtb-aarch64",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-64kb",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-64kb",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-azure",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-azure",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-default",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-default",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-default-base",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1.160000.2.8",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-default-base",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1.160000.2.8",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-docs",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-docs",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-kvmsmall",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-kvmsmall",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-obs-build",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-obs-qa",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-obs-qa",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-rt",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-source",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-source",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-syms",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-syms",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "kernel-zfcpdump",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "OPENSUSE-SU-2026:20416-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-20416-1",
      "released": "2026-03-25T08:49:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-zfcpdump",
      "release": "sles 16.0",
      "fixedVersion": "6.12.0-160000.27.1",
      "fix": "SUSE-SU-2026:20931-1",
      "url": "https://patchblox.com/security/fix/linux/suse-su-2026-20931-1",
      "released": "2026-03-25T08:48:43Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "6.18.8-1",
      "fix": "DEBIAN-CVE-2026-23018",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-23018",
      "released": "2026-01-31T12:16:05Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}