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FKIE_CVE-2026-89491

Vulnerability from fkie_nvd - Published: 2026-09-11 20:19 - Updated: 2026-09-14 13:19
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: ocfs2: cluster: don't sleep while holding o2hb_live_lock in o2hb_region_pin() Patch series "ocfs2: cluster: o2hb_region_pin() fixes", v2. This series fixes three related issues in o2hb_region_pin(), all are from the original implementation in commit: 58a3158a5d17 ("ocfs2/cluster: Pin/unpin o2hb regions"): 1) It is called with o2hb_live_lock (a spinlock) held, but the underlying configfs_depend_item() sleeps (takes inode rwsem and pins the filesystem). This triggers BUG under CONFIG_DEBUG_ATOMIC_SLEEP. 2) When called from the configfs drop_item callback, it creates a lock order inversion: parent inode_lock -> configfs root inode_lock, which can deadlock against subsystem unregistration paths taking root -> parent. 3) If pinning fails partway through o2hb_region_inc_user(), the o2hb_dependent_users counter is leaked and partially-pinned regions are never released, leaving heartbeat regions unprotected on subsequent mounts. Patch 1 reworks o2hb_region_pin() to drop o2hb_live_lock across each sleeping configfs_depend_item() call, using a config_item reference to keep the region alive while unlocked. Patch 2 adds a from_callback parameter to select configfs_depend_item_unlocked() when called from configfs context, avoiding the inode_lock nesting. Patch 3 fixes the error path in o2hb_region_inc_user() to unpin and decrement the counter on failure. This patch (of 3): o2hb_region_pin() is always called with the o2hb_live_lock spinlock held (from o2hb_region_inc_user() and o2hb_heartbeat_group_drop_item()), but it calls o2nm_depend_item() -> configfs_depend_item(), which sleeps: it pins the configfs filesystem and takes the configfs root inode rwsem. Under CONFIG_DEBUG_ATOMIC_SLEEP this triggers: BUG: sleeping function called from invalid context at kernel/locking/rwsem.c in_atomic(): 1, ... name: mount.ocfs2 down_write configfs_depend_item o2hb_region_pin o2hb_region_inc_user o2hb_register_callback dlm_register_domain_handlers ... ocfs2_dlm_init ocfs2_mount_volume ocfs2_fill_super Rework o2hb_region_pin() to pin one region at a time with the lock dropped across the sleeping call: under o2hb_live_lock find the next eligible region and take a config_item reference to keep it alive, drop the lock, call o2nm_depend_item(), then retake the lock and record the pin. The config_item_put() is done with the lock released as well, since o2hb_region_release() also acquires o2hb_live_lock and can sleep. The region list may change while unlocked, so the scan restarts from the top after each pin. Local heartbeat still pins only the matching region; global heartbeat pins all eligible regions. The unpin path is unaffected: configfs_undepend_item() only takes a spinlock and does not sleep.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0cbc2f20a6ea7b4a59efa9171b7c694cdd196507
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3b790774280a610f8bdbd5d4260a07345bcf8e04
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/470212a5eefabcc16b8e2f7fe2844b8737fe571c
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/49002acc520c61002ad195894ac391c94317d3ba
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4d64f8da82fb9e8dbd5aa9b64c9bb6ac0decea03
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/af09df89db9a68a1d76df0f75667998135bc8d65
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c9be4de77f97f383b750698e1517fd296041f4bb
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ce035f208d68b812d83e5482980f2b1c88a9cd94
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ocfs2/cluster/heartbeat.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4d64f8da82fb9e8dbd5aa9b64c9bb6ac0decea03",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            },
            {
              "lessThan": "3b790774280a610f8bdbd5d4260a07345bcf8e04",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            },
            {
              "lessThan": "0cbc2f20a6ea7b4a59efa9171b7c694cdd196507",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            },
            {
              "lessThan": "c9be4de77f97f383b750698e1517fd296041f4bb",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            },
            {
              "lessThan": "49002acc520c61002ad195894ac391c94317d3ba",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            },
            {
              "lessThan": "ce035f208d68b812d83e5482980f2b1c88a9cd94",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            },
            {
              "lessThan": "470212a5eefabcc16b8e2f7fe2844b8737fe571c",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            },
            {
              "lessThan": "af09df89db9a68a1d76df0f75667998135bc8d65",
              "status": "affected",
              "version": "58a3158a5d17ddf4894db9e8ccaf92093ff8e42e",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ocfs2/cluster/heartbeat.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.38"
            },
            {
              "lessThan": "2.6.38",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.270",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.221",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: cluster: don\u0027t sleep while holding o2hb_live_lock in o2hb_region_pin()\n\nPatch series \"ocfs2: cluster: o2hb_region_pin() fixes\", v2.\n\nThis series fixes three related issues in o2hb_region_pin(), all are from\nthe original implementation in commit: 58a3158a5d17 (\"ocfs2/cluster:\nPin/unpin o2hb regions\"):\n\n1) It is called with o2hb_live_lock (a spinlock) held, but the\n   underlying configfs_depend_item() sleeps (takes inode rwsem and\n   pins the filesystem).  This triggers BUG under\n   CONFIG_DEBUG_ATOMIC_SLEEP.\n\n2) When called from the configfs drop_item callback, it creates a\n   lock order inversion: parent inode_lock -\u003e configfs root\n   inode_lock, which can deadlock against subsystem unregistration\n   paths taking root -\u003e parent.\n\n3) If pinning fails partway through o2hb_region_inc_user(), the\n   o2hb_dependent_users counter is leaked and partially-pinned\n   regions are never released, leaving heartbeat regions\n   unprotected on subsequent mounts.\n\nPatch 1 reworks o2hb_region_pin() to drop o2hb_live_lock across each\nsleeping configfs_depend_item() call, using a config_item reference to\nkeep the region alive while unlocked.\n\nPatch 2 adds a from_callback parameter to select\nconfigfs_depend_item_unlocked() when called from configfs context,\navoiding the inode_lock nesting.\n\nPatch 3 fixes the error path in o2hb_region_inc_user() to unpin and\ndecrement the counter on failure.\n\n\nThis patch (of 3):\n\no2hb_region_pin() is always called with the o2hb_live_lock spinlock held\n(from o2hb_region_inc_user() and o2hb_heartbeat_group_drop_item()), but it\ncalls o2nm_depend_item() -\u003e configfs_depend_item(), which sleeps: it pins\nthe configfs filesystem and takes the configfs root inode rwsem.  Under\nCONFIG_DEBUG_ATOMIC_SLEEP this triggers:\n\n  BUG: sleeping function called from invalid context at kernel/locking/rwsem.c\n  in_atomic(): 1, ... name: mount.ocfs2\n    down_write\n    configfs_depend_item\n    o2hb_region_pin\n    o2hb_region_inc_user\n    o2hb_register_callback\n    dlm_register_domain_handlers\n    ...\n    ocfs2_dlm_init\n    ocfs2_mount_volume\n    ocfs2_fill_super\n\nRework o2hb_region_pin() to pin one region at a time with the lock dropped\nacross the sleeping call: under o2hb_live_lock find the next eligible\nregion and take a config_item reference to keep it alive, drop the lock,\ncall o2nm_depend_item(), then retake the lock and record the pin.  The\nconfig_item_put() is done with the lock released as well, since\no2hb_region_release() also acquires o2hb_live_lock and can sleep.  The\nregion list may change while unlocked, so the scan restarts from the top\nafter each pin.  Local heartbeat still pins only the matching region;\nglobal heartbeat pins all eligible regions.\n\nThe unpin path is unaffected: configfs_undepend_item() only takes a\nspinlock and does not sleep."
    }
  ],
  "id": "CVE-2026-89491",
  "lastModified": "2026-09-14T13:19:06.090",
  "metrics": {},
  "published": "2026-09-11T20:19:30.943",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0cbc2f20a6ea7b4a59efa9171b7c694cdd196507"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3b790774280a610f8bdbd5d4260a07345bcf8e04"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/470212a5eefabcc16b8e2f7fe2844b8737fe571c"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/49002acc520c61002ad195894ac391c94317d3ba"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4d64f8da82fb9e8dbd5aa9b64c9bb6ac0decea03"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/af09df89db9a68a1d76df0f75667998135bc8d65"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c9be4de77f97f383b750698e1517fd296041f4bb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ce035f208d68b812d83e5482980f2b1c88a9cd94"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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