{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2021-47492",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-05-22T06:20:56.201Z",
        "datePublished": "2024-05-22T08:19:40.759Z",
        "dateUpdated": "2024-08-04T05:39:59.622Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2024-05-29T05:08:54.202Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm, thp: bail out early in collapse_file for writeback page\n\nCurrently collapse_file does not explicitly check PG_writeback, instead,\npage_has_private and try_to_release_page are used to filter writeback\npages.  This does not work for xfs with blocksize equal to or larger\nthan pagesize, because in such case xfs has no page->private.\n\nThis makes collapse_file bail out early for writeback page.  Otherwise,\nxfs end_page_writeback will panic as follows.\n\n  page:fffffe00201bcc80 refcount:0 mapcount:0 mapping:ffff0003f88c86a8 index:0x0 pfn:0x84ef32\n  aops:xfs_address_space_operations [xfs] ino:30000b7 dentry name:\"libtest.so\"\n  flags: 0x57fffe0000008027(locked|referenced|uptodate|active|writeback)\n  raw: 57fffe0000008027 ffff80001b48bc28 ffff80001b48bc28 ffff0003f88c86a8\n  raw: 0000000000000000 0000000000000000 00000000ffffffff ffff0000c3e9a000\n  page dumped because: VM_BUG_ON_PAGE(((unsigned int) page_ref_count(page) + 127u <= 127u))\n  page->mem_cgroup:ffff0000c3e9a000\n  ------------[ cut here ]------------\n  kernel BUG at include/linux/mm.h:1212!\n  Internal error: Oops - BUG: 0 [#1] SMP\n  Modules linked in:\n  BUG: Bad page state in process khugepaged  pfn:84ef32\n   xfs(E)\n  page:fffffe00201bcc80 refcount:0 mapcount:0 mapping:0 index:0x0 pfn:0x84ef32\n   libcrc32c(E) rfkill(E) aes_ce_blk(E) crypto_simd(E) ...\n  CPU: 25 PID: 0 Comm: swapper/25 Kdump: loaded Tainted: ...\n  pstate: 60400005 (nZCv daif +PAN -UAO -TCO BTYPE=--)\n  Call trace:\n    end_page_writeback+0x1c0/0x214\n    iomap_finish_page_writeback+0x13c/0x204\n    iomap_finish_ioend+0xe8/0x19c\n    iomap_writepage_end_bio+0x38/0x50\n    bio_endio+0x168/0x1ec\n    blk_update_request+0x278/0x3f0\n    blk_mq_end_request+0x34/0x15c\n    virtblk_request_done+0x38/0x74 [virtio_blk]\n    blk_done_softirq+0xc4/0x110\n    __do_softirq+0x128/0x38c\n    __irq_exit_rcu+0x118/0x150\n    irq_exit+0x1c/0x30\n    __handle_domain_irq+0x8c/0xf0\n    gic_handle_irq+0x84/0x108\n    el1_irq+0xcc/0x180\n    arch_cpu_idle+0x18/0x40\n    default_idle_call+0x4c/0x1a0\n    cpuidle_idle_call+0x168/0x1e0\n    do_idle+0xb4/0x104\n    cpu_startup_entry+0x30/0x9c\n    secondary_start_kernel+0x104/0x180\n  Code: d4210000 b0006161 910c8021 94013f4d (d4210000)\n  ---[ end trace 4a88c6a074082f8c ]---\n  Kernel panic - not syncing: Oops - BUG: Fatal exception in interrupt"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "mm/khugepaged.c"
                    ],
                    "versions": [
                        {
                            "version": "99cb0dbd47a1",
                            "lessThan": "69a7fa5cb0de",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "99cb0dbd47a1",
                            "lessThan": "5e669d8ab30a",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "99cb0dbd47a1",
                            "lessThan": "74c42e1baacf",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "mm/khugepaged.c"
                    ],
                    "versions": [
                        {
                            "version": "5.4",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.4",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.10.77",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.14.16",
                            "lessThanOrEqual": "5.14.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.15",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/69a7fa5cb0de06c8956b040f19a7248c8c8308ca"
                },
                {
                    "url": "https://git.kernel.org/stable/c/5e669d8ab30ab61dec3c36e27b4711f07611e6fc"
                },
                {
                    "url": "https://git.kernel.org/stable/c/74c42e1baacf206338b1dd6b6199ac964512b5bb"
                }
            ],
            "title": "mm, thp: bail out early in collapse_file for writeback page",
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                "engine": "bippy-a5840b7849dd"
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                "title": "CISA ADP Vulnrichment",
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                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2021-47492",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
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                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
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                                ],
                                "version": "2.0.3",
                                "timestamp": "2024-05-22T19:45:29.189112Z"
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                    "dateUpdated": "2024-06-04T17:14:55.710Z"
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                    "shortName": "CVE",
                    "dateUpdated": "2024-08-04T05:39:59.622Z"
                },
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://git.kernel.org/stable/c/69a7fa5cb0de06c8956b040f19a7248c8c8308ca",
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