{
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        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "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."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
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                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
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                                            "version_name": "cb658a453b93",
                                            "version_value": "319116227e52"
                                        },
                                        {
                                            "version_value": "not down converted",
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                                                        "version": "4.11",
                                                        "status": "affected"
                                                    },
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                                                        "version": "0",
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                                                        "lessThanOrEqual": "4.14.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
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                                                    {
                                                        "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",
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                                                        "version": "5.11.22",
                                                        "lessThanOrEqual": "5.11.*",
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                "url": "https://git.kernel.org/stable/c/319116227e52d49eee671f0aa278bac89b3c1b69",
                "refsource": "MISC",
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