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CVE-2026-98342

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: dmaengine: wait for RCU readers before releasing dma_device dma_issue_pending_all() walks the dma_device_list with list_for_each_entry_rcu() under rcu_read_lock(). dma_device_release() unlinks the device with list_del_rcu() and then calls device->device_release() (which in many drivers, such as plx_dma.c, directly calls kfree()). Because there is no grace period between unlinking the device and freeing it, concurrent RCU readers in dma_issue_pending_all() can access the device after it has been freed. The lockless walk originally relied on clients holding a dmaengine reference to pin the provider module, and therefore the device, for as long as they might traverse the list. Commit 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") decoupled the dma_device lifetime from the module reference, so the device can now be released while a reader is still walking the list. Add synchronize_rcu() before the device is freed, so RCU readers are guaranteed to have finished. Keep it unconditional: providers that do not implement device_release() free the device themselves once dma_async_device_unregister() returns. This call will delay for a grace period with dma_list_mutex held, which is safe and only teardown path is delayed.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-10-06 09:18:27.003000
Last modified
2026-10-19 10:18:36.560000
View original CVE JSON
{
  "id": "CVE-2026-98342",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-06T09:18:27.003",
  "lastModified": "2026-10-19T10:18:36.560",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndmaengine: wait for RCU readers before releasing dma_device\n\ndma_issue_pending_all() walks the dma_device_list with\nlist_for_each_entry_rcu() under rcu_read_lock(). dma_device_release()\nunlinks the device with list_del_rcu() and then calls\ndevice->device_release() (which in many drivers, such as plx_dma.c,\ndirectly calls kfree()).\n\nBecause there is no grace period between unlinking the device and\nfreeing it, concurrent RCU readers in dma_issue_pending_all() can\naccess the device after it has been freed.\n\nThe lockless walk originally relied on clients holding a dmaengine\nreference to pin the provider module, and therefore the device, for as\nlong as they might traverse the list. Commit 8ad342a86359 (\"dmaengine:\nAdd reference counting to dma_device struct\") decoupled the dma_device\nlifetime from the module reference, so the device can now be released\nwhile a reader is still walking the list.\n\nAdd synchronize_rcu() before the device is freed, so RCU readers are\nguaranteed to have finished. Keep it unconditional: providers that do\nnot implement device_release() free the device themselves once\ndma_async_device_unregister() returns. This call will delay for a grace\nperiod with dma_list_mutex held, which is safe and only teardown path is\ndelayed."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/dma/dmaengine.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2ba05622b8b143b0c95968ba59bddfbd6d2f2559",
              "lessThan": "ac8ce9f89638d6d79875cca7d8ae42566a9bde15",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2ba05622b8b143b0c95968ba59bddfbd6d2f2559",
              "lessThan": "14578c78405d51fa92e4ada4502a45f537c0fcb8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2ba05622b8b143b0c95968ba59bddfbd6d2f2559",
              "lessThan": "cbb3310a5167e868a5e763e32b9a23b4d50669ee",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2ba05622b8b143b0c95968ba59bddfbd6d2f2559",
              "lessThan": "8577a5ec4f7e00443015ef99f646def093121a1b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2ba05622b8b143b0c95968ba59bddfbd6d2f2559",
              "lessThan": "4448a539a0c39141cccc67be6cacde0f35024313",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2ba05622b8b143b0c95968ba59bddfbd6d2f2559",
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              "versionType": "git",
              "status": "affected"
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            {
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              "versionType": "git",
              "status": "affected"
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            {
              "version": "2ba05622b8b143b0c95968ba59bddfbd6d2f2559",
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              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/dma/dmaengine.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2.6.29",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "2.6.29",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.271",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.222",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.189",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.158",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.112",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.54",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.8",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/14578c78405d51fa92e4ada4502a45f537c0fcb8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4448a539a0c39141cccc67be6cacde0f35024313",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4aed7e47a10b94ea3c5171e8d1382081accd2e03",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8577a5ec4f7e00443015ef99f646def093121a1b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ac8ce9f89638d6d79875cca7d8ae42566a9bde15",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cbb3310a5167e868a5e763e32b9a23b4d50669ee",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/dc750422170a563c7a81f6e49d36bb02c62ae37f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fc1f4884f1d46fc7a8cee6e2997ecc9e8d1c7f77",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}