CVE-2026-99202 (GCVE-0-2026-99202)

Vulnerability from cvelistv5 – Published: 2026-10-28 10:35 – Updated: 2026-10-30 12:42
VLAI
Title
scsi: libsas: Fix SMP IO deadlock during HA resume
Summary
In the Linux kernel, the following vulnerability has been resolved: scsi: libsas: Fix SMP IO deadlock during HA resume smp_execute_task_sg() calls pm_runtime_get_sync() on the host before issuing an SMP command. When that command is itself issued from the HA resume path, the get_sync() deadlocks: it waits for the ongoing resume (the device is RPM_RESUMING), while the resume is blocked in sas_drain_work() waiting for that same SMP IO to complete. The deadlock needs an expander-attached SATA disk. During sas_resume_ha() -> sas_drain_work(), DISCE_RESUME -> sas_resume_sata() -> ata_sas_port_resume() requests ATA_EH_RESET, and the hard reset for such a disk is done via SMP PHY CONTROL (sas_ata_hard_reset() -> sas_phy_reset() -> sas_smp_phy_control() -> smp_execute_task_sg()). Direct-attached SATA resets through lldd_control_phy() and SSP devices use TMFs, so neither hits this. Replace the get_sync()/put_sync() pair with pm_runtime_get_noresume()/pm_runtime_put(). smp_execute_task_sg() only needs to hold off autosuspend while the SMP is in flight, and it must not try to resume the host: a sync resume issued from the HA resume path itself is what deadlocks, and by the time sas_resume_ha() runs, hw_init has already reinitialized the hardware, so the device is accessible without one. The usage reference is still required. Discovery work normally runs inside an event worker's PM reference, taken at sas_notify_port_event() notify time and held until the handler has flushed the disco queue. sas_rediscover_ex_phy() however requeues DISCE_REVALIDATE_DOMAIN from within the revalidation worker itself, and flush_workqueue() does not wait for work items queued during execution, so that chained revalidation runs with no outer PM reference - without the get_noresume(), its SMP could race autosuspend. For the BSG path, sas_smp_handler() is the only caller which may find the host autosuspended: expander SMP requests do not go through any SCSI device request queue, so nothing else in that path holds the host awake. Resume it there with pm_runtime_resume_and_get() and check the result.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6971 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 09357f067122e2e28ec52e27013a1660a1571618 , < ab91a558084fdb8cca4919ffb769ca4328e91bbd (git)
Affected: e50a6523a603594a6d92cdecfe11997d639410a3 , < 6078a5369f9e8d22bb03b8890cb0bb47c91a5017 (git)
Affected: c391b5899dd46485a5893696c12ae3e95a3a7325 , < 7004c18c38aaa2b87164b54dd77c320b4c63b89b (git)
Affected: 9e24b47ef81d43b3fb1b14294f09991640c79fcc , < c9fb89246d9922ac0a45d504adb03e0bb971310c (git)
Affected: 3dbbbf656b850c9c8de05df6ad4a1dfc6ff02845 , < 08b95ef36a64c3ae4490794bed3c35d0c3354e85 (git)
Affected: 3dbbbf656b850c9c8de05df6ad4a1dfc6ff02845 , < 81e097a064b28b4a1f6ca1a8b433e659c1bd64c0 (git)
Affected: b9c44a14062093e9fc2d6bddc696cfceadb482d7 (git)
Affected: 6.1.183 , < 6.1.191 (semver)
Affected: 6.6.151 , < 6.6.161 (semver)
Affected: 6.12.103 , < 6.12.115 (semver)
Affected: 6.18.44 , < 6.18.59 (semver)
Affected: 7.1.8 , < 7.2 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 7.2
Unaffected: 0 , < 7.2 (semver)
Unaffected: 6.1.191 , ≤ 6.1.* (semver)
Unaffected: 6.6.161 , ≤ 6.6.* (semver)
Unaffected: 6.12.115 , ≤ 6.12.* (semver)
Unaffected: 6.18.59 , ≤ 6.18.* (semver)
Unaffected: 7.2.13 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: libsas: Fix SMP IO deadlock during HA resume\n\nsmp_execute_task_sg() calls pm_runtime_get_sync() on the host before\nissuing an SMP command. When that command is itself issued from the HA\nresume path, the get_sync() deadlocks: it waits for the ongoing resume\n(the device is RPM_RESUMING), while the resume is blocked in\nsas_drain_work() waiting for that same SMP IO to complete.\n\nThe deadlock needs an expander-attached SATA disk. During\nsas_resume_ha() -\u003e sas_drain_work(), DISCE_RESUME -\u003e sas_resume_sata()\n-\u003e ata_sas_port_resume() requests ATA_EH_RESET, and the hard reset for\nsuch a disk is done via SMP PHY CONTROL (sas_ata_hard_reset() -\u003e\nsas_phy_reset() -\u003e sas_smp_phy_control() -\u003e\nsmp_execute_task_sg()). Direct-attached SATA resets through\nlldd_control_phy() and SSP devices use TMFs, so neither hits this.\n\nReplace the get_sync()/put_sync() pair with\npm_runtime_get_noresume()/pm_runtime_put(). smp_execute_task_sg() only\nneeds to hold off autosuspend while the SMP is in flight, and it must\nnot try to resume the host: a sync resume issued from the HA resume path\nitself is what deadlocks, and by the time sas_resume_ha() runs, hw_init\nhas already reinitialized the hardware, so the device is accessible\nwithout one.\n\nThe usage reference is still required. Discovery work normally runs\ninside an event worker\u0027s PM reference, taken at sas_notify_port_event()\nnotify time and held until the handler has flushed the disco\nqueue. sas_rediscover_ex_phy() however requeues DISCE_REVALIDATE_DOMAIN\nfrom within the revalidation worker itself, and flush_workqueue() does\nnot wait for work items queued during execution, so that chained\nrevalidation runs with no outer PM reference - without the\nget_noresume(), its SMP could race autosuspend.\n\nFor the BSG path, sas_smp_handler() is the only caller which may find\nthe host autosuspended: expander SMP requests do not go through any SCSI\ndevice request queue, so nothing else in that path holds the host\nawake. Resume it there with pm_runtime_resume_and_get() and check the\nresult."
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          "url": "https://git.kernel.org/stable/c/81e097a064b28b4a1f6ca1a8b433e659c1bd64c0"
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      "title": "scsi: libsas: Fix SMP IO deadlock during HA resume",
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    "dateReserved": "2026-09-25T10:25:14.400Z",
    "dateUpdated": "2026-10-30T12:42:52.198Z",
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: libsas: Fix SMP IO deadlock during HA resume\n\nsmp_execute_task_sg() calls pm_runtime_get_sync() on the host before\nissuing an SMP command. When that command is itself issued from the HA\nresume path, the get_sync() deadlocks: it waits for the ongoing resume\n(the device is RPM_RESUMING), while the resume is blocked in\nsas_drain_work() waiting for that same SMP IO to complete.\n\nThe deadlock needs an expander-attached SATA disk. During\nsas_resume_ha() -\u003e sas_drain_work(), DISCE_RESUME -\u003e sas_resume_sata()\n-\u003e ata_sas_port_resume() requests ATA_EH_RESET, and the hard reset for\nsuch a disk is done via SMP PHY CONTROL (sas_ata_hard_reset() -\u003e\nsas_phy_reset() -\u003e sas_smp_phy_control() -\u003e\nsmp_execute_task_sg()). Direct-attached SATA resets through\nlldd_control_phy() and SSP devices use TMFs, so neither hits this.\n\nReplace the get_sync()/put_sync() pair with\npm_runtime_get_noresume()/pm_runtime_put(). smp_execute_task_sg() only\nneeds to hold off autosuspend while the SMP is in flight, and it must\nnot try to resume the host: a sync resume issued from the HA resume path\nitself is what deadlocks, and by the time sas_resume_ha() runs, hw_init\nhas already reinitialized the hardware, so the device is accessible\nwithout one.\n\nThe usage reference is still required. Discovery work normally runs\ninside an event worker\u0027s PM reference, taken at sas_notify_port_event()\nnotify time and held until the handler has flushed the disco\nqueue. sas_rediscover_ex_phy() however requeues DISCE_REVALIDATE_DOMAIN\nfrom within the revalidation worker itself, and flush_workqueue() does\nnot wait for work items queued during execution, so that chained\nrevalidation runs with no outer PM reference - without the\nget_noresume(), its SMP could race autosuspend.\n\nFor the BSG path, sas_smp_handler() is the only caller which may find\nthe host autosuspended: expander SMP requests do not go through any SCSI\ndevice request queue, so nothing else in that path holds the host\nawake. Resume it there with pm_runtime_resume_and_get() and check the\nresult."
          }
        ],
        "id": "CVE-2026-99202",
        "lastModified": "2026-10-30T13:21:52.657",
        "metrics": {},
        "published": "2026-10-28T11:17:41.377",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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          {
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            "url": "https://git.kernel.org/stable/c/6078a5369f9e8d22bb03b8890cb0bb47c91a5017"
          },
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            "url": "https://git.kernel.org/stable/c/7004c18c38aaa2b87164b54dd77c320b4c63b89b"
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            "url": "https://git.kernel.org/stable/c/c9fb89246d9922ac0a45d504adb03e0bb971310c"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    }
  }
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

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