{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2021-46982",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-46982",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-02-28T08:13:11.585Z",
    "updatedAt": "2026-05-11T13:45:40.030Z",
    "importedAt": "2026-10-24T01:56:36.661Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "f2fs: compress: fix race condition of overwrite vs truncate",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: compress: fix race condition of overwrite vs truncate\n\npos_fsstress testcase complains a panic as belew:\n\n------------[ cut here ]------------\nkernel BUG at fs/f2fs/compress.c:1082!\ninvalid opcode: 0000 [#1] SMP PTI\nCPU: 4 PID: 2753477 Comm: kworker/u16:2 Tainted: G           OE     5.12.0-rc1-custom #1\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014\nWorkqueue: writeback wb_workfn (flush-252:16)\nRIP: 0010:prepare_compress_overwrite+0x4c0/0x760 [f2fs]\nCall Trace:\n f2fs_prepare_compress_overwrite+0x5f/0x80 [f2fs]\n f2fs_write_cache_pages+0x468/0x8a0 [f2fs]\n f2fs_write_data_pages+0x2a4/0x2f0 [f2fs]\n do_writepages+0x38/0xc0\n __writeback_single_inode+0x44/0x2a0\n writeback_sb_inodes+0x223/0x4d0\n __writeback_inodes_wb+0x56/0xf0\n wb_writeback+0x1dd/0x290\n wb_workfn+0x309/0x500\n process_one_work+0x220/0x3c0\n worker_thread+0x53/0x420\n kthread+0x12f/0x150\n ret_from_fork+0x22/0x30\n\nThe root cause is truncate() may race with overwrite as below,\nso that one reference count left in page can not guarantee the\npage attaching in mapping tree all the time, after truncation,\nlater find_lock_page() may return NULL pointer.\n\n- prepare_compress_overwrite\n - f2fs_pagecache_get_page\n - unlock_page\n\t\t\t\t\t- f2fs_setattr\n\t\t\t\t\t - truncate_setsize\n\t\t\t\t\t  - truncate_inode_page\n\t\t\t\t\t   - delete_from_page_cache\n - find_lock_page\n\nFix this by avoiding referencing updated page.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "4c8ff7095bef64fc47e996a938f7d57f9e077da3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5639b73fd3bc6fc8ca72e3a9ac15aacaabd7ebff"
            },
            {
              "version": "4c8ff7095bef64fc47e996a938f7d57f9e077da3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "64acb100fe3beb5d20184d0ae3307235bd3555c4"
            },
            {
              "version": "4c8ff7095bef64fc47e996a938f7d57f9e077da3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "936158b15e2648253afb824d252c910c496d34b5"
            },
            {
              "version": "4c8ff7095bef64fc47e996a938f7d57f9e077da3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a949dc5f2c5cfe0c910b664650f45371254c0744"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.6",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.6"
            },
            {
              "version": "5.10.38",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.11.22",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.11.*"
            },
            {
              "version": "5.12.5",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.12.*"
            },
            {
              "version": "5.13",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}