{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2022-48731",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/kmemleak: avoid scanning potential huge holes\n\nWhen using devm_request_free_mem_region() and devm_memremap_pages() to\nadd ZONE_DEVICE memory, if requested free mem region's end pfn were\nhuge(e.g., 0x400000000), the node_end_pfn() will be also huge (see\nmove_pfn_range_to_zone()).  Thus it creates a huge hole between\nnode_start_pfn() and node_end_pfn().\n\nWe found on some AMD APUs, amdkfd requested such a free mem region and\ncreated a huge hole.  In such a case, following code snippet was just\ndoing busy test_bit() looping on the huge hole.\n\n  for (pfn = start_pfn; pfn < end_pfn; pfn++) {\n\tstruct page *page = pfn_to_online_page(pfn);\n\t\tif (!page)\n\t\t\tcontinue;\n\t...\n  }\n\nSo we got a soft lockup:\n\n  watchdog: BUG: soft lockup - CPU#6 stuck for 26s! [bash:1221]\n  CPU: 6 PID: 1221 Comm: bash Not tainted 5.15.0-custom #1\n  RIP: 0010:pfn_to_online_page+0x5/0xd0\n  Call Trace:\n    ? kmemleak_scan+0x16a/0x440\n    kmemleak_write+0x306/0x3a0\n    ? common_file_perm+0x72/0x170\n    full_proxy_write+0x5c/0x90\n    vfs_write+0xb9/0x260\n    ksys_write+0x67/0xe0\n    __x64_sys_write+0x1a/0x20\n    do_syscall_64+0x3b/0xc0\n    entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nI did some tests with the patch.\n\n(1) amdgpu module unloaded\n\nbefore the patch:\n\n  real    0m0.976s\n  user    0m0.000s\n  sys     0m0.968s\n\nafter the patch:\n\n  real    0m0.981s\n  user    0m0.000s\n  sys     0m0.973s\n\n(2) amdgpu module loaded\n\nbefore the patch:\n\n  real    0m35.365s\n  user    0m0.000s\n  sys     0m35.354s\n\nafter the patch:\n\n  real    0m1.049s\n  user    0m0.000s\n  sys     0m1.042s"
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "1da177e4c3f4",
                                            "version_value": "d3533ee20e9a"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "5.4.178",
                                                        "lessThanOrEqual": "5.4.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.10.99",
                                                        "lessThanOrEqual": "5.10.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.15.22",
                                                        "lessThanOrEqual": "5.15.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.16.8",
                                                        "lessThanOrEqual": "5.16.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "5.17",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/d3533ee20e9a0e2e8f60384da7450d43d1c63d1a",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/d3533ee20e9a0e2e8f60384da7450d43d1c63d1a"
            },
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                "url": "https://git.kernel.org/stable/c/352715593e81b917ce1b321e794549815b850134",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/352715593e81b917ce1b321e794549815b850134"
            },
            {
                "url": "https://git.kernel.org/stable/c/a5389c80992f0001ee505838fe6a8b20897ce96e",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/a5389c80992f0001ee505838fe6a8b20897ce96e"
            },
            {
                "url": "https://git.kernel.org/stable/c/cebb0aceb21ad91429617a40e3a17444fabf1529",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/cebb0aceb21ad91429617a40e3a17444fabf1529"
            },
            {
                "url": "https://git.kernel.org/stable/c/c10a0f877fe007021d70f9cada240f42adc2b5db",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/c10a0f877fe007021d70f9cada240f42adc2b5db"
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    "generator": {
        "engine": "bippy-7d53e8ef8be4"
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