GSD-2021-46993

Vulnerability from gsd - Updated: 2024-02-28 06:03
Details
In the Linux kernel, the following vulnerability has been resolved: sched: Fix out-of-bound access in uclamp Util-clamp places tasks in different buckets based on their clamp values for performance reasons. However, the size of buckets is currently computed using a rounding division, which can lead to an off-by-one error in some configurations. For instance, with 20 buckets, the bucket size will be 1024/20=51. A task with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly, correct indexes are in range [0,19], hence leading to an out of bound memory access. Clamp the bucket id to fix the issue.
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{
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-46993"
      ],
      "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched: Fix out-of-bound access in uclamp\n\nUtil-clamp places tasks in different buckets based on their clamp values\nfor performance reasons. However, the size of buckets is currently\ncomputed using a rounding division, which can lead to an off-by-one\nerror in some configurations.\n\nFor instance, with 20 buckets, the bucket size will be 1024/20=51. A\ntask with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly,\ncorrect indexes are in range [0,19], hence leading to an out of bound\nmemory access.\n\nClamp the bucket id to fix the issue.",
      "id": "GSD-2021-46993",
      "modified": "2024-02-28T06:03:57.479342Z",
      "schema_version": "1.4.0"
    }
  },
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        "ID": "CVE-2021-46993",
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                  {
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                    "version": {
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                        {
                          "version_affected": "\u003c",
                          "version_name": "69842cba9ace",
                          "version_value": "687f523c134b"
                        },
                        {
                          "version_value": "not down converted",
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched: Fix out-of-bound access in uclamp\n\nUtil-clamp places tasks in different buckets based on their clamp values\nfor performance reasons. However, the size of buckets is currently\ncomputed using a rounding division, which can lead to an off-by-one\nerror in some configurations.\n\nFor instance, with 20 buckets, the bucket size will be 1024/20=51. A\ntask with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly,\ncorrect indexes are in range [0,19], hence leading to an out of bound\nmemory access.\n\nClamp the bucket id to fix the issue."
          }
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      },
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      "problemtype": {
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                "value": "n/a"
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    },
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        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched: Fix out-of-bound access in uclamp\n\nUtil-clamp places tasks in different buckets based on their clamp values\nfor performance reasons. However, the size of buckets is currently\ncomputed using a rounding division, which can lead to an off-by-one\nerror in some configurations.\n\nFor instance, with 20 buckets, the bucket size will be 1024/20=51. A\ntask with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly,\ncorrect indexes are in range [0,19], hence leading to an out of bound\nmemory access.\n\nClamp the bucket id to fix the issue."
          }
        ],
        "id": "CVE-2021-46993",
        "lastModified": "2024-02-28T14:06:45.783",
        "metrics": {},
        "published": "2024-02-28T09:15:37.880",
        "references": [
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            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Awaiting Analysis"
      }
    }
  }
}



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