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FKIE_CVE-2026-80536

Vulnerability from fkie_nvd - Published: 2026-08-26 15:17 - Updated: 2026-08-27 13:18
Severity
8.4 (High) - CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: xfs: bounds-check buffer log item's dirty bitmap xlog_recover_do_reg_buffer() replays each dirty region described by a buffer log item's bitmap into the buffer read for that item: memcpy(xfs_buf_offset(bp, (uint)bit << XFS_BLF_SHIFT), item->ri_buf[i].iov_base, nbits << XFS_BLF_SHIFT); The destination offset (bit/nbits, from the logged dirty bitmap) and the buffer size (from the logged blf_len) are both attacker-controlled and otherwise unrelated, yet the only thing bounding the copy is an ASSERT(), which compiles away on production kernels. A crafted image logging a small blf_len together with a bitmap bit past the end of that buffer drives the memcpy() past the buffer's allocation, corrupting adjacent kernel heap during mount-time log recovery. This is reachable by anyone who can get a crafted image mounted -- the malicious-filesystem threat model XFS already guards against elsewhere. Turn the ASSERT() into a real XFS_IS_CORRUPT() check that aborts recovery of the buffer with -EFSCORRUPTED, consistent with the validate-and-fail idiom already used in xlog_recover_do_inode_buffer() and xfs_dquot_item_recover.c. xlog_recover_do_reg_buffer() therefore becomes STATIC int and its three callers propagate the error. Found and confirmed with KASAN on a CONFIG_XFS_DEBUG=n build: the crafted image trips a slab-out-of-bounds write before this change and fails recovery cleanly with -EFSCORRUPTED after it.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7e32d4eebae6ca24f8a673c107fd7eca1f47afc2
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/813f8136a2ce1fee266d02a7df73db6e8a541604
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/acb4e26295e7f0e685815a3fd3d70bd8329cefa1
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b7528b42813f02724a78fce1da24d69d1bfc4d38
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/edaf5b6bd625356893da20d69a259b34a9de2694
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f3859c35a4fbc1c1c58431f684f808e43696891d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f7b5fa83e2c192be922121b764415fa8c7549ea1
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f8288214459ead7e87d26e5822f62c14a4f2ed6b
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/xfs/xfs_buf_item_recover.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "acb4e26295e7f0e685815a3fd3d70bd8329cefa1",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "f3859c35a4fbc1c1c58431f684f808e43696891d",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "f7b5fa83e2c192be922121b764415fa8c7549ea1",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "b7528b42813f02724a78fce1da24d69d1bfc4d38",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "7e32d4eebae6ca24f8a673c107fd7eca1f47afc2",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "f8288214459ead7e87d26e5822f62c14a4f2ed6b",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "edaf5b6bd625356893da20d69a259b34a9de2694",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "813f8136a2ce1fee266d02a7df73db6e8a541604",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/xfs/xfs_buf_item_recover.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.12"
            },
            {
              "lessThan": "2.6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.267",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.218",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.185",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.154",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.106",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.46",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: bounds-check buffer log item\u0027s dirty bitmap\n\nxlog_recover_do_reg_buffer() replays each dirty region described by a\nbuffer log item\u0027s bitmap into the buffer read for that item:\n\n\tmemcpy(xfs_buf_offset(bp, (uint)bit \u003c\u003c XFS_BLF_SHIFT),\n\t\titem-\u003eri_buf[i].iov_base,\n\t\tnbits \u003c\u003c XFS_BLF_SHIFT);\n\nThe destination offset (bit/nbits, from the logged dirty bitmap) and the\nbuffer size (from the logged blf_len) are both attacker-controlled and\notherwise unrelated, yet the only thing bounding the copy is an ASSERT(),\nwhich compiles away on production kernels. A crafted image logging a\nsmall blf_len together with a bitmap bit past the end of that buffer\ndrives the memcpy() past the buffer\u0027s allocation, corrupting adjacent\nkernel heap during mount-time log recovery. This is reachable by anyone\nwho can get a crafted image mounted -- the malicious-filesystem threat\nmodel XFS already guards against elsewhere.\n\nTurn the ASSERT() into a real XFS_IS_CORRUPT() check that aborts recovery\nof the buffer with -EFSCORRUPTED, consistent with the validate-and-fail\nidiom already used in xlog_recover_do_inode_buffer() and\nxfs_dquot_item_recover.c. xlog_recover_do_reg_buffer() therefore becomes\nSTATIC int and its three callers propagate the error.\n\nFound and confirmed with KASAN on a CONFIG_XFS_DEBUG=n build: the crafted\nimage trips a slab-out-of-bounds write before this change and fails\nrecovery cleanly with -EFSCORRUPTED after it."
    }
  ],
  "id": "CVE-2026-80536",
  "lastModified": "2026-08-27T13:18:38.940",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 8.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-26T15:17:07.777",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7e32d4eebae6ca24f8a673c107fd7eca1f47afc2"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/813f8136a2ce1fee266d02a7df73db6e8a541604"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/acb4e26295e7f0e685815a3fd3d70bd8329cefa1"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b7528b42813f02724a78fce1da24d69d1bfc4d38"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/edaf5b6bd625356893da20d69a259b34a9de2694"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f3859c35a4fbc1c1c58431f684f808e43696891d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f7b5fa83e2c192be922121b764415fa8c7549ea1"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f8288214459ead7e87d26e5822f62c14a4f2ed6b"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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