FKIE_CVE-2026-89926

Vulnerability from fkie_nvd - Published: 2026-09-16 11:17 - Updated: 2026-09-16 11:17
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Fix length check __import_wp_info() struct kvm_hw_breakpoint::len is a __u64 that is fully controlled by user space. This is then assigned to wp_info->len, which is an int. The bounds check is done on the truncated value while the allocation uses the untruncated one: wp_info->len = bp_data->len; [...] if (wp_info->len < 0 || wp_info->len > MAX_WP_SIZE) return -EINVAL; wp_info->old_data = kmalloc(bp_data->len, GFP_KERNEL_ACCOUNT); Use the validated value for the allocation as intended. Without this fix userspace can trigger >4GB allocations which will fail and result in a WARN due to MAX_PAGE_ORDER.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3fe801db90bdeefb0bbdda42d832846b53f64f8a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4c07680a467e2f7697245bcd11691bffb2a6f0ed
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/71153d3262517e1c02c3a66aa5094f279b2d1454
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/aef540194effd768bed0bd2e6a74fe135a3d7c3a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b94ab9caa5d72c78226121cccff5e33f946da900
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/beb9c55af609c4c7308259d7191688c75a4e3d4a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fec89d327d9b2b669b5bbdac209386c6317c3722
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/s390/kvm/guestdbg.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "aef540194effd768bed0bd2e6a74fe135a3d7c3a",
              "status": "affected",
              "version": "27291e2165b6de70c476b7b675308113edd69a60",
              "versionType": "git"
            },
            {
              "lessThan": "71153d3262517e1c02c3a66aa5094f279b2d1454",
              "status": "affected",
              "version": "27291e2165b6de70c476b7b675308113edd69a60",
              "versionType": "git"
            },
            {
              "lessThan": "fec89d327d9b2b669b5bbdac209386c6317c3722",
              "status": "affected",
              "version": "27291e2165b6de70c476b7b675308113edd69a60",
              "versionType": "git"
            },
            {
              "lessThan": "b94ab9caa5d72c78226121cccff5e33f946da900",
              "status": "affected",
              "version": "27291e2165b6de70c476b7b675308113edd69a60",
              "versionType": "git"
            },
            {
              "lessThan": "beb9c55af609c4c7308259d7191688c75a4e3d4a",
              "status": "affected",
              "version": "27291e2165b6de70c476b7b675308113edd69a60",
              "versionType": "git"
            },
            {
              "lessThan": "3fe801db90bdeefb0bbdda42d832846b53f64f8a",
              "status": "affected",
              "version": "27291e2165b6de70c476b7b675308113edd69a60",
              "versionType": "git"
            },
            {
              "lessThan": "4c07680a467e2f7697245bcd11691bffb2a6f0ed",
              "status": "affected",
              "version": "27291e2165b6de70c476b7b675308113edd69a60",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/s390/kvm/guestdbg.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.16"
            },
            {
              "lessThan": "3.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.221",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.188",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.110",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.51",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "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\nKVM: s390: Fix length check __import_wp_info()\n\nstruct kvm_hw_breakpoint::len is a __u64 that is fully controlled by user\nspace. This is then assigned to wp_info-\u003elen, which is an int. The bounds\ncheck is done on the truncated value while the allocation uses the\nuntruncated one:\n\n\twp_info-\u003elen = bp_data-\u003elen;\n\t[...]\n\tif (wp_info-\u003elen \u003c 0 || wp_info-\u003elen \u003e MAX_WP_SIZE)\n\t\treturn -EINVAL;\n\n\twp_info-\u003eold_data = kmalloc(bp_data-\u003elen, GFP_KERNEL_ACCOUNT);\n\nUse the validated value for the allocation as intended. Without this\nfix userspace can trigger \u003e4GB allocations which will fail and result\nin a WARN due to MAX_PAGE_ORDER."
    }
  ],
  "id": "CVE-2026-89926",
  "lastModified": "2026-09-16T11:17:01.777",
  "metrics": {},
  "published": "2026-09-16T11:17:01.777",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3fe801db90bdeefb0bbdda42d832846b53f64f8a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4c07680a467e2f7697245bcd11691bffb2a6f0ed"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/71153d3262517e1c02c3a66aa5094f279b2d1454"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/aef540194effd768bed0bd2e6a74fe135a3d7c3a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b94ab9caa5d72c78226121cccff5e33f946da900"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/beb9c55af609c4c7308259d7191688c75a4e3d4a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fec89d327d9b2b669b5bbdac209386c6317c3722"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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