{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2021-47508",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-05-22T06:20:56.206Z",
        "datePublished": "2024-05-24T15:01:54.048Z",
        "dateUpdated": "2024-09-11T17:33:22.299Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2024-05-29T05:09:11.002Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: free exchange changeset on failures\n\nFstests runs on my VMs have show several kmemleak reports like the following.\n\n  unreferenced object 0xffff88811ae59080 (size 64):\n    comm \"xfs_io\", pid 12124, jiffies 4294987392 (age 6.368s)\n    hex dump (first 32 bytes):\n      00 c0 1c 00 00 00 00 00 ff cf 1c 00 00 00 00 00  ................\n      90 97 e5 1a 81 88 ff ff 90 97 e5 1a 81 88 ff ff  ................\n    backtrace:\n      [<00000000ac0176d2>] ulist_add_merge+0x60/0x150 [btrfs]\n      [<0000000076e9f312>] set_state_bits+0x86/0xc0 [btrfs]\n      [<0000000014fe73d6>] set_extent_bit+0x270/0x690 [btrfs]\n      [<000000004f675208>] set_record_extent_bits+0x19/0x20 [btrfs]\n      [<00000000b96137b1>] qgroup_reserve_data+0x274/0x310 [btrfs]\n      [<0000000057e9dcbb>] btrfs_check_data_free_space+0x5c/0xa0 [btrfs]\n      [<0000000019c4511d>] btrfs_delalloc_reserve_space+0x1b/0xa0 [btrfs]\n      [<000000006d37e007>] btrfs_dio_iomap_begin+0x415/0x970 [btrfs]\n      [<00000000fb8a74b8>] iomap_iter+0x161/0x1e0\n      [<0000000071dff6ff>] __iomap_dio_rw+0x1df/0x700\n      [<000000002567ba53>] iomap_dio_rw+0x5/0x20\n      [<0000000072e555f8>] btrfs_file_write_iter+0x290/0x530 [btrfs]\n      [<000000005eb3d845>] new_sync_write+0x106/0x180\n      [<000000003fb505bf>] vfs_write+0x24d/0x2f0\n      [<000000009bb57d37>] __x64_sys_pwrite64+0x69/0xa0\n      [<000000003eba3fdf>] do_syscall_64+0x43/0x90\n\nIn case brtfs_qgroup_reserve_data() or btrfs_delalloc_reserve_metadata()\nfail the allocated extent_changeset will not be freed.\n\nSo in btrfs_check_data_free_space() and btrfs_delalloc_reserve_space()\nfree the allocated extent_changeset to get rid of the allocated memory.\n\nThe issue currently only happens in the direct IO write path, but only\nafter 65b3c08606e5 (\"btrfs: fix ENOSPC failure when attempting direct IO\nwrite into NOCOW range\"), and also at defrag_one_locked_target(). Every\nother place is always calling extent_changeset_free() even if its call\nto btrfs_delalloc_reserve_space() or btrfs_check_data_free_space() has\nfailed."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/btrfs/delalloc-space.c"
                    ],
                    "versions": [
                        {
                            "version": "1da177e4c3f4",
                            "lessThan": "ca06c5cb1b6d",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "1da177e4c3f4",
                            "lessThan": "da5e817d9d75",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/btrfs/delalloc-space.c"
                    ],
                    "versions": [
                        {
                            "version": "5.15.8",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.16",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/ca06c5cb1b6dbfe67655b33c02fc394d65824519"
                },
                {
                    "url": "https://git.kernel.org/stable/c/da5e817d9d75422eaaa05490d0b9a5e328fc1a51"
                }
            ],
            "title": "btrfs: free exchange changeset on failures",
            "x_generator": {
                "engine": "bippy-a5840b7849dd"
            }
        },
        "adp": [
            {
                "providerMetadata": {
                    "orgId": "af854a3a-2127-422b-91ae-364da2661108",
                    "shortName": "CVE",
                    "dateUpdated": "2024-08-04T05:39:59.770Z"
                },
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://git.kernel.org/stable/c/ca06c5cb1b6dbfe67655b33c02fc394d65824519",
                        "tags": [
                            "x_transferred"
                        ]
                    },
                    {
                        "url": "https://git.kernel.org/stable/c/da5e817d9d75422eaaa05490d0b9a5e328fc1a51",
                        "tags": [
                            "x_transferred"
                        ]
                    }
                ]
            },
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2021-47508",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2024-09-10T15:35:39.656794Z"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2024-09-11T17:33:22.299Z"
                }
            }
        ]
    }
}