{
  "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-2022-49272",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2022-49272",
    "idYear": 2022,
    "status": "PUBLISHED",
    "publishedAt": "2025-02-26T01:56:18.626Z",
    "updatedAt": "2026-05-11T18:56:29.104Z",
    "importedAt": "2026-10-24T01:56:49.724Z",
    "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": "ALSA: pcm: Fix potential AB/BA lock with buffer_mutex and mmap_lock",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: pcm: Fix potential AB/BA lock with buffer_mutex and mmap_lock\n\nsyzbot caught a potential deadlock between the PCM\nruntime->buffer_mutex and the mm->mmap_lock.  It was brought by the\nrecent fix to cover the racy read/write and other ioctls, and in that\ncommit, I overlooked a (hopefully only) corner case that may take the\nrevert lock, namely, the OSS mmap.  The OSS mmap operation\nexceptionally allows to re-configure the parameters inside the OSS\nmmap syscall, where mm->mmap_mutex is already held.  Meanwhile, the\ncopy_from/to_user calls at read/write operations also take the\nmm->mmap_lock internally, hence it may lead to a AB/BA deadlock.\n\nA similar problem was already seen in the past and we fixed it with a\nrefcount (in commit b248371628aa).  The former fix covered only the\ncall paths with OSS read/write and OSS ioctls, while we need to cover\nthe concurrent access via both ALSA and OSS APIs now.\n\nThis patch addresses the problem above by replacing the buffer_mutex\nlock in the read/write operations with a refcount similar as we've\nused for OSS.  The new field, runtime->buffer_accessing, keeps the\nnumber of concurrent read/write operations.  Unlike the former\nbuffer_mutex protection, this protects only around the\ncopy_from/to_user() calls; the other codes are basically protected by\nthe PCM stream lock.  The refcount can be a negative, meaning blocked\nby the ioctls.  If a negative value is seen, the read/write aborts\nwith -EBUSY.  In the ioctl side, OTOH, they check this refcount, too,\nand set to a negative value for blocking unless it's already being\naccessed.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "73867cb2bc7dfa7fbd219e53a0b68d253d8fda09",
              "status": "affected",
              "versionType": "git",
              "lessThan": "7e9133607e1501c94881be35e118d8f84d96dcb4"
            },
            {
              "version": "b3830197aa7413c65767cf5a1aa8775c83f0dbf7",
              "status": "affected",
              "versionType": "git",
              "lessThan": "40f4cffbe13a51faf136faf5f9ef6847782cd595"
            },
            {
              "version": "08d1807f097a63ea00a7067dad89c1c81cb2115e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9661bf674d6a82b76e4ae424438a8ce1e3ed855d"
            },
            {
              "version": "8527c8f052fb42091c6569cb928e472376a4a889",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9017201e8d8c6d1472273361389ed431188584a0"
            },
            {
              "version": "47711ff10c7e126702cfa725f6d86ef529d15a5f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "7777744e92a0b30e3e0cce2758d911837011ebd9"
            },
            {
              "version": "4d1b0ace2d56dc27cc4921eda7fae57f77f03eb5",
              "status": "affected",
              "versionType": "git",
              "lessThan": "abedf0d08c79d76da0d6fa0d5dbbc98871dcbc2e"
            },
            {
              "version": "dd2f8c684da3e226e5ec7a81c89ff5fd4a957a03",
              "status": "affected",
              "versionType": "git",
              "lessThan": "be9813ad2fc8f0885f5ce6925af0d993ce5da4e5"
            },
            {
              "version": "dca947d4d26dbf925a64a6cfb2ddbc035e831a3d",
              "status": "affected",
              "versionType": "git",
              "lessThan": "bc55cfd5718c7c23e5524582e9fa70b4d10f2433"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "5.10.109",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.10.110"
            },
            {
              "version": "5.15.32",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.15.33"
            },
            {
              "version": "5.16.18",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.16.19"
            },
            {
              "version": "5.17.1",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.17.2"
            }
          ]
        }
      ]
    }
  }
}