CVE-2026-89647 (GCVE-0-2026-89647)
Vulnerability from cvelistv5
Published
2026-09-11 19:45
Modified
2026-10-30 12:32
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: ceph: do not repeat ceph_trim_dentries() if no progress possible ceph_cap_reclaim_work() re-queues itself for as long as ceph_trim_dentries() returns -EAGAIN, which happens whenever a lease walk exhausts its `nr_to_scan` budget. This creates a busy loop that consumes CPU without making any progress when there is nothing to reclaim: with no cap pressure (`count==0`) and every scanned lease still valid, each pass runs the full scan budget down to zero and returns `-EAGAIN`, only to be queued again immediately. The dir-lease walk made this worse. When `expire_dir_lease` is `false` (i.e. we have no intention of reclaiming dir leases), __dir_lease_check() returned `TOUCH` for every valid lease. `TOUCH` moves the dentry to the tail of the list and resets `di->time` via __dentry_dir_lease_touch(), so a walk over N valid leases pointlessly rewrote the list, refreshed the timestamps (preventing them from ever aging out) and always drained `nr_to_scan`, guaranteeing the `-EAGAIN` requeue. Fix this in three steps: - Return `KEEP` instead of `TOUCH` when `expire_dir_lease` is `false`. If we are not going to reclaim the lease, leave it in place instead of churning the list and resetting its timestamp; the walk then terminates naturally (or via `STOP` at the first fresh lease). - Only return `-EAGAIN` from the first (dentry-lease) walk when something was actually freed. A full batch that frees nothing means retrying the same list immediately is futile; fall through to the dir-lease walk instead. - After both walks, bail out with success (0) when nothing was freed and there is no cap pressure (`count==0`). There is no reason to keep retrying when we are not over the cap limit and made no progress. Under real cap pressure (`count>0`) the reclaim path is unchanged and still retries via `-EAGAIN`. Without this patch, I saw 500 ceph_trim_dentries() calls per second on our web servers. This is very visible in `/proc/lock_stat` (5 minute capture): class name con-bounces contentions waittime-min waittime-max waittime-total waittime-avg acq-bounces acquisitions holdtime-min holdtime-max holdtime-total holdtime-avg &mdsc->dentry_list_lock: 126180 128218 0.04 8063.44 15986965.20 124.69 1573354 5296812 0.04 8291.28 74164526.48 14.00 ----------------------- &mdsc->dentry_list_lock 111736 [<000000007b11e319>] __ceph_dentry_dir_lease_touch+0x7c/0xa8 &mdsc->dentry_list_lock 2631 [<0000000050597999>] __dentry_leases_walk+0x64/0x2c8 &mdsc->dentry_list_lock 3878 [<00000000c0022f62>] __ceph_dentry_lease_touch+0x5c/0xa8 &mdsc->dentry_list_lock 9973 [<000000002f27cb6f>] __dentry_lease_unlist+0x50/0xa0 ----------------------- &mdsc->dentry_list_lock 123621 [<0000000050597999>] __dentry_leases_walk+0x64/0x2c8 &mdsc->dentry_list_lock 1822 [<000000007b11e319>] __ceph_dentry_dir_lease_touch+0x7c/0xa8 &mdsc->dentry_list_lock 2720 [<000000002f27cb6f>] __dentry_lease_unlist+0x50/0xa0 &mdsc->dentry_list_lock 55 [<00000000c0022f62>] __ceph_dentry_lease_touch+0x5c/0xa8 With this patch: class name con-bounces contentions waittime-min waittime-max waittime-total waittime-avg acq-bounces acquisitions holdtime-min holdtime-max holdtime-total holdtime-avg &mdsc->dentry_list_lock: 1203 1215 0.16 408.88 33082.88 27.23 4320501 7357389 0.04 500.64 1961578.00 0.27 ----------------------- &mdsc->dentry_list_lock 1029 [<000000003c9aea8a>] __ceph_dentry_dir_lease_touch+0x7c/0xa8 &mdsc->dentry_list_lock 1 ---truncated---
References
Impacted products
Vendor Product Version
Linux Linux Version: 37c4efc1ddf98ba8b234d116d863a9464445901e
Version: 37c4efc1ddf98ba8b234d116d863a9464445901e
Version: 37c4efc1ddf98ba8b234d116d863a9464445901e
Version: 37c4efc1ddf98ba8b234d116d863a9464445901e
Version: 37c4efc1ddf98ba8b234d116d863a9464445901e
Version: 37c4efc1ddf98ba8b234d116d863a9464445901e
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: do not repeat ceph_trim_dentries() if no progress possible\n\nceph_cap_reclaim_work() re-queues itself for as long as\nceph_trim_dentries() returns -EAGAIN, which happens whenever a lease\nwalk exhausts its `nr_to_scan` budget.  This creates a busy loop that\nconsumes CPU without making any progress when there is nothing to\nreclaim: with no cap pressure (`count==0`) and every scanned lease\nstill valid, each pass runs the full scan budget down to zero and\nreturns `-EAGAIN`, only to be queued again immediately.\n\nThe dir-lease walk made this worse.  When `expire_dir_lease` is\n`false` (i.e. we have no intention of reclaiming dir leases),\n__dir_lease_check() returned `TOUCH` for every valid lease.  `TOUCH`\nmoves the dentry to the tail of the list and resets `di-\u003etime` via\n__dentry_dir_lease_touch(), so a walk over N valid leases pointlessly\nrewrote the list, refreshed the timestamps (preventing them from ever\naging out) and always drained `nr_to_scan`, guaranteeing the `-EAGAIN`\nrequeue.\n\nFix this in three steps:\n\n - Return `KEEP` instead of `TOUCH` when `expire_dir_lease` is\n   `false`.  If we are not going to reclaim the lease, leave it in\n   place instead of churning the list and resetting its timestamp; the\n   walk then terminates naturally (or via `STOP` at the first fresh\n   lease).\n\n - Only return `-EAGAIN` from the first (dentry-lease) walk when something\n   was actually freed.  A full batch that frees nothing means retrying\n   the same list immediately is futile; fall through to the dir-lease\n   walk instead.\n\n - After both walks, bail out with success (0) when nothing was freed\n   and there is no cap pressure (`count==0`).  There is no reason to\n   keep retrying when we are not over the cap limit and made no\n   progress.\n\nUnder real cap pressure (`count\u003e0`) the reclaim path is unchanged and\nstill retries via `-EAGAIN`.\n\nWithout this patch, I saw 500 ceph_trim_dentries() calls per second on\nour web servers.  This is very visible in `/proc/lock_stat` (5 minute\ncapture):\n\n              class name    con-bounces    contentions   waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg\n\n \u0026mdsc-\u003edentry_list_lock:        126180         128218           0.04        8063.44    15986965.20         124.69        1573354        5296812           0.04        8291.28    74164526.48          14.00\n -----------------------\n \u0026mdsc-\u003edentry_list_lock         111736          [\u003c000000007b11e319\u003e] __ceph_dentry_dir_lease_touch+0x7c/0xa8\n \u0026mdsc-\u003edentry_list_lock           2631          [\u003c0000000050597999\u003e] __dentry_leases_walk+0x64/0x2c8\n \u0026mdsc-\u003edentry_list_lock           3878          [\u003c00000000c0022f62\u003e] __ceph_dentry_lease_touch+0x5c/0xa8\n \u0026mdsc-\u003edentry_list_lock           9973          [\u003c000000002f27cb6f\u003e] __dentry_lease_unlist+0x50/0xa0\n -----------------------\n \u0026mdsc-\u003edentry_list_lock         123621          [\u003c0000000050597999\u003e] __dentry_leases_walk+0x64/0x2c8\n \u0026mdsc-\u003edentry_list_lock           1822          [\u003c000000007b11e319\u003e] __ceph_dentry_dir_lease_touch+0x7c/0xa8\n \u0026mdsc-\u003edentry_list_lock           2720          [\u003c000000002f27cb6f\u003e] __dentry_lease_unlist+0x50/0xa0\n \u0026mdsc-\u003edentry_list_lock             55          [\u003c00000000c0022f62\u003e] __ceph_dentry_lease_touch+0x5c/0xa8\n\nWith this patch:\n\n              class name    con-bounces    contentions   waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg\n\n \u0026mdsc-\u003edentry_list_lock:          1203           1215           0.16         408.88       33082.88          27.23        4320501        7357389           0.04         500.64     1961578.00           0.27\n -----------------------\n \u0026mdsc-\u003edentry_list_lock           1029          [\u003c000000003c9aea8a\u003e] __ceph_dentry_dir_lease_touch+0x7c/0xa8\n \u0026mdsc-\u003edentry_list_lock            1\n---truncated---"
        }
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      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
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          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - fs/ceph registers ceph_export_ops, so remote nfsd/ksmbd readdir and lookup on an exported CephFS mount populate dentry and dir-lease lists and drive ceph_trim_dentries() via the cap-reclaim workqueue; a compromised MDS on the existing client TCP session can also keep those leases valid.\nAC:L - Default caps_max leaves count==0, so expire_dir_lease is false and valid dir leases are TOUCHed until nr_to_scan hits zero; ceph_cap_reclaim_work() then immediately requeues on -EAGAIN. An attacker who walks or creates many dentries, or a peer that grants many still-valid leases, triggers this deterministically with no race.\nPR:N - In the network-export scenario the attacker needs no local account or capability on the victim host; guest or anonymous NFS/SMB exports of CephFS, and a remote MDS peer on an already-connected kernel client, are reasonable high-severity deployments matching other Ceph client CVEs.\nUI:N - After CephFS is mounted and optionally exported, delayed_work periodically queues reclaim and the attacker\u2019s own readdir/lookup or MDS lease traffic is enough; no separate victim mount, open, or confirmation is required at exploit time.\nS:U - The busy loop, CPU burn, and dentry_list_lock contention stay inside the host kernel CephFS client and do not cross a VM, IOMMU, or sandbox boundary to another security authority.\nC:N - The defect only rescans and TOUCHes still-valid dentry leases; it does not perform an out-of-bounds read, use-after-free, or any other kernel-memory disclosure.\nI:N - The walk only reshuffles lease-list order and refreshes dentry timestamps; there is no memory corruption, arbitrary write, or control-flow hijack primitive.\nA:H - ceph_cap_reclaim_work() immediately requeues itself on -EAGAIN, forming an unbounded busy loop on the max_active=1 ceph-cap workqueue (observed ~500 iterations/s) that starves cap-release work, burns CPU, and contends dentry_list_lock enough to stall Ceph directory operations."
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        "dateUpdated": "2026-10-30T12:32:29.127Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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      "references": [
        {
          "url": "https://git.kernel.org/stable/c/f2f6daf8e99e15d636b1706bb4efd9a856195324"
        },
        {
          "url": "https://git.kernel.org/stable/c/dd2e9824e5e7dba406005ff779a107f773175a76"
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          "url": "https://git.kernel.org/stable/c/5a541eb401acb89d791da41189d7a79220164b93"
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        {
          "url": "https://git.kernel.org/stable/c/37d6edb2f03b29399a3a337fae78674de51e1695"
        },
        {
          "url": "https://git.kernel.org/stable/c/3d122b2feb1dd76bb5041bdea5e1e1b007d8d415"
        },
        {
          "url": "https://git.kernel.org/stable/c/e7d7aa7b730178278109c41fa1b17b06873065d5"
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      ],
      "title": "ceph: do not repeat ceph_trim_dentries() if no progress possible",
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89647",
    "datePublished": "2026-09-11T19:45:38.593Z",
    "dateReserved": "2026-09-11T19:38:34.741Z",
    "dateUpdated": "2026-10-30T12:32:29.127Z",
    "state": "PUBLISHED"
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    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-89647\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-10-16T19:25:05.998836Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-10-16T19:25:07.431Z\"}}], \"cna\": {\"title\": \"ceph: do not repeat ceph_trim_dentries() if no progress possible\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 7.5, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:N - fs/ceph registers ceph_export_ops, so remote nfsd/ksmbd readdir and lookup on an exported CephFS mount populate dentry and dir-lease lists and drive ceph_trim_dentries() via the cap-reclaim workqueue; a compromised MDS on the existing client TCP session can also keep those leases valid.\\nAC:L - Default caps_max leaves count==0, so expire_dir_lease is false and valid dir leases are TOUCHed until nr_to_scan hits zero; ceph_cap_reclaim_work() then immediately requeues on -EAGAIN. An attacker who walks or creates many dentries, or a peer that grants many still-valid leases, triggers this deterministically with no race.\\nPR:N - In the network-export scenario the attacker needs no local account or capability on the victim host; guest or anonymous NFS/SMB exports of CephFS, and a remote MDS peer on an already-connected kernel client, are reasonable high-severity deployments matching other Ceph client CVEs.\\nUI:N - After CephFS is mounted and optionally exported, delayed_work periodically queues reclaim and the attacker\\u2019s own readdir/lookup or MDS lease traffic is enough; no separate victim mount, open, or confirmation is required at exploit time.\\nS:U - The busy loop, CPU burn, and dentry_list_lock contention stay inside the host kernel CephFS client and do not cross a VM, IOMMU, or sandbox boundary to another security authority.\\nC:N - The defect only rescans and TOUCHes still-valid dentry leases; it does not perform an out-of-bounds read, use-after-free, or any other kernel-memory disclosure.\\nI:N - The walk only reshuffles lease-list order and refreshes dentry timestamps; there is no memory corruption, arbitrary write, or control-flow hijack primitive.\\nA:H - ceph_cap_reclaim_work() immediately requeues itself on -EAGAIN, forming an unbounded busy loop on the max_active=1 ceph-cap workqueue (observed ~500 iterations/s) that starves cap-release work, burns CPU, and contends dentry_list_lock enough to stall Ceph directory operations.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"37c4efc1ddf98ba8b234d116d863a9464445901e\", \"lessThan\": \"f2f6daf8e99e15d636b1706bb4efd9a856195324\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"37c4efc1ddf98ba8b234d116d863a9464445901e\", \"lessThan\": \"dd2e9824e5e7dba406005ff779a107f773175a76\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"37c4efc1ddf98ba8b234d116d863a9464445901e\", \"lessThan\": \"5a541eb401acb89d791da41189d7a79220164b93\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"37c4efc1ddf98ba8b234d116d863a9464445901e\", \"lessThan\": \"37d6edb2f03b29399a3a337fae78674de51e1695\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"37c4efc1ddf98ba8b234d116d863a9464445901e\", \"lessThan\": \"3d122b2feb1dd76bb5041bdea5e1e1b007d8d415\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"37c4efc1ddf98ba8b234d116d863a9464445901e\", \"lessThan\": \"e7d7aa7b730178278109c41fa1b17b06873065d5\", \"versionType\": \"git\"}], \"programFiles\": [\"fs/ceph/dir.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"5.1\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"5.1\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"6.1.191\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.160\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.109\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.18.50\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.18.*\"}, {\"status\": \"unaffected\", \"version\": \"7.2.4\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"7.2.*\"}, {\"status\": \"unaffected\", \"version\": \"7.3\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"fs/ceph/dir.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/f2f6daf8e99e15d636b1706bb4efd9a856195324\"}, {\"url\": \"https://git.kernel.org/stable/c/dd2e9824e5e7dba406005ff779a107f773175a76\"}, {\"url\": \"https://git.kernel.org/stable/c/5a541eb401acb89d791da41189d7a79220164b93\"}, {\"url\": \"https://git.kernel.org/stable/c/37d6edb2f03b29399a3a337fae78674de51e1695\"}, {\"url\": \"https://git.kernel.org/stable/c/3d122b2feb1dd76bb5041bdea5e1e1b007d8d415\"}, {\"url\": \"https://git.kernel.org/stable/c/e7d7aa7b730178278109c41fa1b17b06873065d5\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nceph: do not repeat ceph_trim_dentries() if no progress possible\\n\\nceph_cap_reclaim_work() re-queues itself for as long as\\nceph_trim_dentries() returns -EAGAIN, which happens whenever a lease\\nwalk exhausts its `nr_to_scan` budget.  This creates a busy loop that\\nconsumes CPU without making any progress when there is nothing to\\nreclaim: with no cap pressure (`count==0`) and every scanned lease\\nstill valid, each pass runs the full scan budget down to zero and\\nreturns `-EAGAIN`, only to be queued again immediately.\\n\\nThe dir-lease walk made this worse.  When `expire_dir_lease` is\\n`false` (i.e. we have no intention of reclaiming dir leases),\\n__dir_lease_check() returned `TOUCH` for every valid lease.  `TOUCH`\\nmoves the dentry to the tail of the list and resets `di-\u003etime` via\\n__dentry_dir_lease_touch(), so a walk over N valid leases pointlessly\\nrewrote the list, refreshed the timestamps (preventing them from ever\\naging out) and always drained `nr_to_scan`, guaranteeing the `-EAGAIN`\\nrequeue.\\n\\nFix this in three steps:\\n\\n - Return `KEEP` instead of `TOUCH` when `expire_dir_lease` is\\n   `false`.  If we are not going to reclaim the lease, leave it in\\n   place instead of churning the list and resetting its timestamp; the\\n   walk then terminates naturally (or via `STOP` at the first fresh\\n   lease).\\n\\n - Only return `-EAGAIN` from the first (dentry-lease) walk when something\\n   was actually freed.  A full batch that frees nothing means retrying\\n   the same list immediately is futile; fall through to the dir-lease\\n   walk instead.\\n\\n - After both walks, bail out with success (0) when nothing was freed\\n   and there is no cap pressure (`count==0`).  There is no reason to\\n   keep retrying when we are not over the cap limit and made no\\n   progress.\\n\\nUnder real cap pressure (`count\u003e0`) the reclaim path is unchanged and\\nstill retries via `-EAGAIN`.\\n\\nWithout this patch, I saw 500 ceph_trim_dentries() calls per second on\\nour web servers.  This is very visible in `/proc/lock_stat` (5 minute\\ncapture):\\n\\n              class name    con-bounces    contentions   waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg\\n\\n \u0026mdsc-\u003edentry_list_lock:        126180         128218           0.04        8063.44    15986965.20         124.69        1573354        5296812           0.04        8291.28    74164526.48          14.00\\n -----------------------\\n \u0026mdsc-\u003edentry_list_lock         111736          [\u003c000000007b11e319\u003e] __ceph_dentry_dir_lease_touch+0x7c/0xa8\\n \u0026mdsc-\u003edentry_list_lock           2631          [\u003c0000000050597999\u003e] __dentry_leases_walk+0x64/0x2c8\\n \u0026mdsc-\u003edentry_list_lock           3878          [\u003c00000000c0022f62\u003e] __ceph_dentry_lease_touch+0x5c/0xa8\\n \u0026mdsc-\u003edentry_list_lock           9973          [\u003c000000002f27cb6f\u003e] __dentry_lease_unlist+0x50/0xa0\\n -----------------------\\n \u0026mdsc-\u003edentry_list_lock         123621          [\u003c0000000050597999\u003e] __dentry_leases_walk+0x64/0x2c8\\n \u0026mdsc-\u003edentry_list_lock           1822          [\u003c000000007b11e319\u003e] __ceph_dentry_dir_lease_touch+0x7c/0xa8\\n \u0026mdsc-\u003edentry_list_lock           2720          [\u003c000000002f27cb6f\u003e] __dentry_lease_unlist+0x50/0xa0\\n \u0026mdsc-\u003edentry_list_lock             55          [\u003c00000000c0022f62\u003e] __ceph_dentry_lease_touch+0x5c/0xa8\\n\\nWith this patch:\\n\\n              class name    con-bounces    contentions   waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces   acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg\\n\\n \u0026mdsc-\u003edentry_list_lock:          1203           1215           0.16         408.88       33082.88          27.23        4320501        7357389           0.04         500.64     1961578.00           0.27\\n -----------------------\\n \u0026mdsc-\u003edentry_list_lock           1029          [\u003c000000003c9aea8a\u003e] __ceph_dentry_dir_lease_touch+0x7c/0xa8\\n \u0026mdsc-\u003edentry_list_lock            1\\n---truncated---\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.191\", \"versionStartIncluding\": \"5.1\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.160\", \"versionStartIncluding\": \"5.1\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.109\", \"versionStartIncluding\": \"5.1\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.18.50\", \"versionStartIncluding\": \"5.1\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.2.4\", \"versionStartIncluding\": \"5.1\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.3\", \"versionStartIncluding\": \"5.1\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-10-30T12:32:29.127Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-89647\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-30T12:32:29.127Z\", \"dateReserved\": \"2026-09-11T19:38:34.741Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2026-09-11T19:45:38.593Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


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