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    "cveMetadata": {
        "cveId": "CVE-2021-46988",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-02-27T18:42:55.948Z",
        "datePublished": "2024-02-28T08:13:15.310Z",
        "dateUpdated": "2024-08-04T05:24:38.475Z"
    },
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                "shortName": "Linux",
                "dateUpdated": "2024-05-29T05:00:04.768Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nuserfaultfd: release page in error path to avoid BUG_ON\n\nConsider the following sequence of events:\n\n1. Userspace issues a UFFD ioctl, which ends up calling into\n   shmem_mfill_atomic_pte(). We successfully account the blocks, we\n   shmem_alloc_page(), but then the copy_from_user() fails. We return\n   -ENOENT. We don't release the page we allocated.\n2. Our caller detects this error code, tries the copy_from_user() after\n   dropping the mmap_lock, and retries, calling back into\n   shmem_mfill_atomic_pte().\n3. Meanwhile, let's say another process filled up the tmpfs being used.\n4. So shmem_mfill_atomic_pte() fails to account blocks this time, and\n   immediately returns - without releasing the page.\n\nThis triggers a BUG_ON in our caller, which asserts that the page\nshould always be consumed, unless -ENOENT is returned.\n\nTo fix this, detect if we have such a \"dangling\" page when accounting\nfails, and if so, release it before returning."
                }
            ],
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                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
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                            "status": "affected",
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                            "status": "affected",
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                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
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                    ],
                    "versions": [
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                            "version": "4.11",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "4.11",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "4.14.233",
                            "lessThanOrEqual": "4.14.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "4.19.191",
                            "lessThanOrEqual": "4.19.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.4.120",
                            "lessThanOrEqual": "5.4.*",
                            "status": "unaffected",
                            "versionType": "custom"
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                        {
                            "version": "5.10.38",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.11.22",
                            "lessThanOrEqual": "5.11.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.12.5",
                            "lessThanOrEqual": "5.12.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.13",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
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                }
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/319116227e52d49eee671f0aa278bac89b3c1b69"
                },
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                    "url": "https://git.kernel.org/stable/c/07c9b834c97d0fa3402fb7f3f3b32df370a6ff1f"
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                    "url": "https://git.kernel.org/stable/c/140cfd9980124aecb6c03ef2e69c72d0548744de"
                },
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                },
                {
                    "url": "https://git.kernel.org/stable/c/7ed9d238c7dbb1fdb63ad96a6184985151b0171c"
                }
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            "title": "userfaultfd: release page in error path to avoid BUG_ON",
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                "title": "CVE Program Container",
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