{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-35798",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix race in read_extent_buffer_pages()\n\nThere are reports from tree-checker that detects corrupted nodes,\nwithout any obvious pattern so possibly an overwrite in memory.\nAfter some debugging it turns out there's a race when reading an extent\nbuffer the uptodate status can be missed.\n\nTo prevent concurrent reads for the same extent buffer,\nread_extent_buffer_pages() performs these checks:\n\n    /* (1) */\n    if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))\n        return 0;\n\n    /* (2) */\n    if (test_and_set_bit(EXTENT_BUFFER_READING, &eb->bflags))\n        goto done;\n\nAt this point, it seems safe to start the actual read operation. Once\nthat completes, end_bbio_meta_read() does\n\n    /* (3) */\n    set_extent_buffer_uptodate(eb);\n\n    /* (4) */\n    clear_bit(EXTENT_BUFFER_READING, &eb->bflags);\n\nNormally, this is enough to ensure only one read happens, and all other\ncallers wait for it to finish before returning.  Unfortunately, there is\na racey interleaving:\n\n    Thread A | Thread B | Thread C\n    ---------+----------+---------\n       (1)   |          |\n             |    (1)   |\n       (2)   |          |\n       (3)   |          |\n       (4)   |          |\n             |    (2)   |\n             |          |    (1)\n\nWhen this happens, thread B kicks of an unnecessary read. Worse, thread\nC will see UPTODATE set and return immediately, while the read from\nthread B is still in progress.  This race could result in tree-checker\nerrors like this as the extent buffer is concurrently modified:\n\n    BTRFS critical (device dm-0): corrupted node, root=256\n    block=8550954455682405139 owner mismatch, have 11858205567642294356\n    expect [256, 18446744073709551360]\n\nFix it by testing UPTODATE again after setting the READING bit, and if\nit's been set, skip the unnecessary read.\n\n[ minor update of changelog ]"
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
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                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "d7172f52e993",
                                            "version_value": "0427c8ef8bbb"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.5",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "6.5",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.6.24",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.7.12",
                                                        "lessThanOrEqual": "6.7.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
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                                                    {
                                                        "version": "6.8.3",
                                                        "lessThanOrEqual": "6.8.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.9",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
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                                                "defaultStatus": "affected"
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    "references": {
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                "name": "https://git.kernel.org/stable/c/2885d54af2c2e1d910e20d5c8045bae40e02fbc1"
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