{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-64289",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T15:36:31.778Z",
        "datePublished": "2026-07-25T08:49:29.434Z",
        "dateUpdated": "2026-08-17T04:52:45.289Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-17T04:52:45.289Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommufd: Set upper bounds on cache invalidation entry_num and entry_len\n\niommufd_hwpt_invalidate() takes a user-controlled entry_num and entry_len,\neach bounded only by U32_MAX. An entry_len beyond the kernel's struct size\nmakes the copy helper verify the extra bytes are zero, scanning that excess\nin one uninterruptible pass; a multi-gigabyte value over zeroed user memory\ntrips the soft-lockup watchdog.\n\nA large entry_num is the other half, driving the backend invalidation loop\nwith no reschedule. The VT-d nested handler, for one, copies each entry and\nflushes caches per iteration, pinning the CPU on a non-preemptible kernel.\n\nCap both in the ioctl. entry_len is held under PAGE_SIZE, above any request\nstruct, and entry_num under 1 << 19, the order of a hardware invalidation\nqueue and well beyond any real batch, bounding the per-call loop length."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/iommu/iommufd/hw_pagetable.c"
                    ],
                    "versions": [
                        {
                            "version": "8c6eabae3807e048b9f17733af5e20500fbf858c",
                            "lessThan": "d2bd041e0efaf7d81789779b135279d18b33d6d5",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8c6eabae3807e048b9f17733af5e20500fbf858c",
                            "lessThan": "32ca4aed2a66205b072fcfecabe220289a8149ff",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8c6eabae3807e048b9f17733af5e20500fbf858c",
                            "lessThan": "2c6381d90898089287e0a358f06f89f6b4b389f2",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8c6eabae3807e048b9f17733af5e20500fbf858c",
                            "lessThan": "4d70986002f2f3eaaed89124fb2522bded38b016",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/iommu/iommufd/hw_pagetable.c"
                    ],
                    "versions": [
                        {
                            "version": "6.8",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.8",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.96",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.39",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.4",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.8",
                                    "versionEndExcluding": "6.12.96"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.8",
                                    "versionEndExcluding": "6.18.39"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.8",
                                    "versionEndExcluding": "7.1.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.8",
                                    "versionEndExcluding": "7.2"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/d2bd041e0efaf7d81789779b135279d18b33d6d5"
                },
                {
                    "url": "https://git.kernel.org/stable/c/32ca4aed2a66205b072fcfecabe220289a8149ff"
                },
                {
                    "url": "https://git.kernel.org/stable/c/2c6381d90898089287e0a358f06f89f6b4b389f2"
                },
                {
                    "url": "https://git.kernel.org/stable/c/4d70986002f2f3eaaed89124fb2522bded38b016"
                }
            ],
            "title": "iommufd: Set upper bounds on cache invalidation entry_num and entry_len",
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}