media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish()

{
  "id": "09c1b2bf357ddb3c625f392ace1f633dbbb777ef570a05678535b7b5d3dfbf87",
  "url": "https://osv.dev/vulnerability/CVE-2023-53458",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish() When the driver calls cx23885_risc_buffer() to prepare the buffer, the function call dma_alloc_coherent may fail, resulting in a empty buffer risc->cpu. Later when we free the buffer or access the buffer, null ptr deref is triggered. This bug is similar to the following one: https://git.linuxtv.org/media_stage.git/commit/?id=2b064d91440b33fba5b452f2d1b31f13ae911d71. We believe the bug can be also dynamically triggered from user side. Similarly, we fix this by checking the return value of cx23885_risc_buffer() and the value of risc->cpu before buffer free.",
    "evidence": "osv:CVE-2023-53458",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.113",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.30",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.3.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2023-53458",
      "aliases": [
        "CVE-2023-53458"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                  "fixed": "f0a06203f2fe63f04311467200c99c4ee1926578"
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                {
                  "fixed": "6738841f6fcf23e9fc30e2449f32fc84ee19c6f1"
                },
                {
                  "fixed": "5b8e5e28e85a546dfccc3895befe0e823fdd7c89"
                },
                {
                  "fixed": "47e8b73bc35d7c54642f78e498697692f6358996"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53458.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "3.18.0"
                },
                {
                  "fixed": "5.15.113"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.30"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.3.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53458.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:23.348154888Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/47e8b73bc35d7c54642f78e498697692f6358996",
        "https://git.kernel.org/stable/c/5b8e5e28e85a546dfccc3895befe0e823fdd7c89",
        "https://git.kernel.org/stable/c/6738841f6fcf23e9fc30e2449f32fc84ee19c6f1",
        "https://git.kernel.org/stable/c/f0a06203f2fe63f04311467200c99c4ee1926578",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53458.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-53458",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53458.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-53458",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 489396,
  "published_at": "2025-10-01T11:42:29.665+00:00"
}