CVE-2025-38627 (GCVE-0-2025-38627)
Vulnerability from cvelistv5
Published
2025-08-22 16:00
Modified
2025-09-29 05:55
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: f2fs: compress: fix UAF of f2fs_inode_info in f2fs_free_dic The decompress_io_ctx may be released asynchronously after I/O completion. If this file is deleted immediately after read, and the kworker of processing post_read_wq has not been executed yet due to high workloads, It is possible that the inode(f2fs_inode_info) is evicted and freed before it is used f2fs_free_dic. The UAF case as below: Thread A Thread B - f2fs_decompress_end_io - f2fs_put_dic - queue_work add free_dic work to post_read_wq - do_unlink - iput - evict - call_rcu This file is deleted after read. Thread C kworker to process post_read_wq - rcu_do_batch - f2fs_free_inode - kmem_cache_free inode is freed by rcu - process_scheduled_works - f2fs_late_free_dic - f2fs_free_dic - f2fs_release_decomp_mem read (dic->inode)->i_compress_algorithm This patch store compress_algorithm and sbi in dic to avoid inode UAF. In addition, the previous solution is deprecated in [1] may cause system hang. [1] https://lore.kernel.org/all/c36ab955-c8db-4a8b-a9d0-f07b5f426c3f@kernel.org
References
Impacted products
Vendor Product Version
Linux Linux Version: bff139b49d9f70c1ac5384aac94554846aa834de
Version: bff139b49d9f70c1ac5384aac94554846aa834de
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/f2fs/compress.c",
            "fs/f2fs/f2fs.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "8fae5b6addd5f6895e03797b56e3c7b9f9cd15c9",
              "status": "affected",
              "version": "bff139b49d9f70c1ac5384aac94554846aa834de",
              "versionType": "git"
            },
            {
              "lessThan": "39868685c2a94a70762bc6d77dc81d781d05bff5",
              "status": "affected",
              "version": "bff139b49d9f70c1ac5384aac94554846aa834de",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/f2fs/compress.c",
            "fs/f2fs/f2fs.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.0"
            },
            {
              "lessThan": "6.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.16.*",
              "status": "unaffected",
              "version": "6.16.1",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.17",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.16.1",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17",
                  "versionStartIncluding": "6.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: compress: fix UAF of f2fs_inode_info in f2fs_free_dic\n\nThe decompress_io_ctx may be released asynchronously after\nI/O completion. If this file is deleted immediately after read,\nand the kworker of processing post_read_wq has not been executed yet\ndue to high workloads, It is possible that the inode(f2fs_inode_info)\nis evicted and freed before it is used f2fs_free_dic.\n\n    The UAF case as below:\n    Thread A                                      Thread B\n    - f2fs_decompress_end_io\n     - f2fs_put_dic\n      - queue_work\n        add free_dic work to post_read_wq\n                                                   - do_unlink\n                                                    - iput\n                                                     - evict\n                                                      - call_rcu\n    This file is deleted after read.\n\n    Thread C                                 kworker to process post_read_wq\n    - rcu_do_batch\n     - f2fs_free_inode\n      - kmem_cache_free\n     inode is freed by rcu\n                                             - process_scheduled_works\n                                              - f2fs_late_free_dic\n                                               - f2fs_free_dic\n                                                - f2fs_release_decomp_mem\n                                      read (dic-\u003einode)-\u003ei_compress_algorithm\n\nThis patch store compress_algorithm and sbi in dic to avoid inode UAF.\n\nIn addition, the previous solution is deprecated in [1] may cause system hang.\n[1] https://lore.kernel.org/all/c36ab955-c8db-4a8b-a9d0-f07b5f426c3f@kernel.org"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-09-29T05:55:05.007Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/8fae5b6addd5f6895e03797b56e3c7b9f9cd15c9"
        },
        {
          "url": "https://git.kernel.org/stable/c/39868685c2a94a70762bc6d77dc81d781d05bff5"
        }
      ],
      "title": "f2fs: compress: fix UAF of f2fs_inode_info in f2fs_free_dic",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-38627",
    "datePublished": "2025-08-22T16:00:35.856Z",
    "dateReserved": "2025-04-16T04:51:24.029Z",
    "dateUpdated": "2025-09-29T05:55:05.007Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-38627\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-08-22T16:15:36.337\",\"lastModified\":\"2025-08-22T18:08:51.663\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nf2fs: compress: fix UAF of f2fs_inode_info in f2fs_free_dic\\n\\nThe decompress_io_ctx may be released asynchronously after\\nI/O completion. If this file is deleted immediately after read,\\nand the kworker of processing post_read_wq has not been executed yet\\ndue to high workloads, It is possible that the inode(f2fs_inode_info)\\nis evicted and freed before it is used f2fs_free_dic.\\n\\n    The UAF case as below:\\n    Thread A                                      Thread B\\n    - f2fs_decompress_end_io\\n     - f2fs_put_dic\\n      - queue_work\\n        add free_dic work to post_read_wq\\n                                                   - do_unlink\\n                                                    - iput\\n                                                     - evict\\n                                                      - call_rcu\\n    This file is deleted after read.\\n\\n    Thread C                                 kworker to process post_read_wq\\n    - rcu_do_batch\\n     - f2fs_free_inode\\n      - kmem_cache_free\\n     inode is freed by rcu\\n                                             - process_scheduled_works\\n                                              - f2fs_late_free_dic\\n                                               - f2fs_free_dic\\n                                                - f2fs_release_decomp_mem\\n                                      read (dic-\u003einode)-\u003ei_compress_algorithm\\n\\nThis patch store compress_algorithm and sbi in dic to avoid inode UAF.\\n\\nIn addition, the previous solution is deprecated in [1] may cause system hang.\\n[1] https://lore.kernel.org/all/c36ab955-c8db-4a8b-a9d0-f07b5f426c3f@kernel.org\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/39868685c2a94a70762bc6d77dc81d781d05bff5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8fae5b6addd5f6895e03797b56e3c7b9f9cd15c9\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.