{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-53125",
  "modified": "2026-10-07T14:35:31Z",
  "upstream": [
    "CVE-2026-53125"
  ],
  "published": "2026-06-24T16:31:02Z",
  "summary": "md: fix array_state=clear sysfs deadlock",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmd: fix array_state=clear sysfs deadlock\n\nWhen \"clear\" is written to array_state, md_attr_store() breaks sysfs\nactive protection so the array can delete itself from its own sysfs\nstore method.\n\nHowever, md_attr_store() currently drops the mddev reference before\ncalling sysfs_unbreak_active_protection(). Once do_md_stop(..., 0)\nhas made the mddev eligible for delayed deletion, the temporary\nkobject reference taken by sysfs_break_active_protection() can become\nthe last kobject reference protecting the md kobject.\n\nThat allows sysfs_unbreak_active_protection() to drop the last\nkobject reference from the current sysfs writer context. kobject\nteardown then recurses into kernfs removal while the current sysfs\nnode is still being unwound, and lockdep reports recursive locking on\nkn->active with kernfs_drain() in the call chain.\n\nReproducer on an existing level:\n1. Create an md0 linear array and activate it:\n   mknod /dev/md0 b 9 0\n   echo none > /sys/block/md0/md/metadata_version\n   echo linear > /sys/block/md0/md/level\n   echo 1 > /sys/block/md0/md/raid_disks\n   echo \"$(cat /sys/class/block/sdb/dev)\" > /sys/block/md0/md/new_dev\n   echo \"$(($(cat /sys/class/block/sdb/size) / 2))\" > \\\n\t/sys/block/md0/md/dev-sdb/size\n   echo 0 > /sys/block/md0/md/dev-sdb/slot\n   echo active > /sys/block/md0/md/array_state\n2. Wait briefly for the array to settle, then clear it:\n   sleep 2\n   echo clear > /sys/block/md0/md/array_state\n\nThe warning looks like:\n\n  WARNING: possible recursive locking detected\n  bash/588 is trying to acquire lock:\n  (kn->active#65) at __kernfs_remove+0x157/0x1d0\n  but task is already holding lock:\n  (kn->active#65) at sysfs_unbreak_active_protection+0x1f/0x40\n  ...\n  Call Trace:\n   kernfs_drain\n   __kernfs_remove\n   kernfs_remove_by_name_ns\n   sysfs_remove_group\n   sysfs_remove_groups\n   __kobject_del\n   kobject_put\n   md_attr_store\n   kernfs_fop_write_iter\n   vfs_write\n   ksys_write\n\nRestore active protection before mddev_put() so the extra sysfs\nkobject reference is dropped while the mddev is still held alive. The\nactual md kobject deletion is then deferred until after the sysfs\nwrite path has fully returned.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:13",
        "name": "linux"
      },
      "versions": [
        "1:6.18.29-1+rpt1"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-2712",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v6",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v7",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v8",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v8-rt",
            "binary_version": "1:6.18.29-1+rpt1"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.18.29-1+rpt1": {
            "linux_commit": "66318c5b5cd8145a662303af12ed39ac07eb27cc",
            "upstream_version": "6.18.29",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.18.33"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-53125"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/62c44566da7493ee48ef17e8507bb798338a07cb"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/92ad0ec509ffb188d8f849b63148664df37b4a52"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/2aa72276fab9851dbd59c2daeb4b590c5a113908"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-06-24T16:31:02Z"
  }
}