{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-38255",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-04-16T04:51:23.997Z",
        "datePublished": "2025-07-09T10:42:33.225Z",
        "dateUpdated": "2026-05-11T21:24:15.704Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T21:24:15.704Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlib/group_cpus: fix NULL pointer dereference from group_cpus_evenly()\n\nWhile testing null_blk with configfs, echo 0 > poll_queues will trigger\nfollowing panic:\n\nBUG: kernel NULL pointer dereference, address: 0000000000000010\nOops: Oops: 0000 [#1] SMP NOPTI\nCPU: 27 UID: 0 PID: 920 Comm: bash Not tainted 6.15.0-02023-gadbdb95c8696-dirty #1238 PREEMPT(undef)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014\nRIP: 0010:__bitmap_or+0x48/0x70\nCall Trace:\n <TASK>\n __group_cpus_evenly+0x822/0x8c0\n group_cpus_evenly+0x2d9/0x490\n blk_mq_map_queues+0x1e/0x110\n null_map_queues+0xc9/0x170 [null_blk]\n blk_mq_update_queue_map+0xdb/0x160\n blk_mq_update_nr_hw_queues+0x22b/0x560\n nullb_update_nr_hw_queues+0x71/0xf0 [null_blk]\n nullb_device_poll_queues_store+0xa4/0x130 [null_blk]\n configfs_write_iter+0x109/0x1d0\n vfs_write+0x26e/0x6f0\n ksys_write+0x79/0x180\n __x64_sys_write+0x1d/0x30\n x64_sys_call+0x45c4/0x45f0\n do_syscall_64+0xa5/0x240\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nRoot cause is that numgrps is set to 0, and ZERO_SIZE_PTR is returned from\nkcalloc(), and later ZERO_SIZE_PTR will be deferenced.\n\nFix the problem by checking numgrps first in group_cpus_evenly(), and\nreturn NULL directly if numgrps is zero.\n\n[yukuai3@huawei.com: also fix the non-SMP version]"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "lib/group_cpus.c"
                    ],
                    "versions": [
                        {
                            "version": "6a6dcae8f486c3f3298d0767d34505121c7b0b81",
                            "lessThan": "64a99eff8dcf1f951a544e6058341b2b19a8fdbd",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "6a6dcae8f486c3f3298d0767d34505121c7b0b81",
                            "lessThan": "29d39e0d5f16c060e32542b2cf351c09fd22b250",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "6a6dcae8f486c3f3298d0767d34505121c7b0b81",
                            "lessThan": "911ef2e8a7de5b2bae8ff11fb0bd01f699e6db65",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "6a6dcae8f486c3f3298d0767d34505121c7b0b81",
                            "lessThan": "df831e97739405ecbaddb85516bc7d4d1c933d6b",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "lib/group_cpus.c"
                    ],
                    "versions": [
                        {
                            "version": "6.3",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.3",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.96",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.36",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.15.5",
                            "lessThanOrEqual": "6.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.16",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.3",
                                    "versionEndExcluding": "6.6.96"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.3",
                                    "versionEndExcluding": "6.12.36"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.3",
                                    "versionEndExcluding": "6.15.5"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.3",
                                    "versionEndExcluding": "6.16"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/64a99eff8dcf1f951a544e6058341b2b19a8fdbd"
                },
                {
                    "url": "https://git.kernel.org/stable/c/29d39e0d5f16c060e32542b2cf351c09fd22b250"
                },
                {
                    "url": "https://git.kernel.org/stable/c/911ef2e8a7de5b2bae8ff11fb0bd01f699e6db65"
                },
                {
                    "url": "https://git.kernel.org/stable/c/df831e97739405ecbaddb85516bc7d4d1c933d6b"
                }
            ],
            "title": "lib/group_cpus: fix NULL pointer dereference from group_cpus_evenly()",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}