{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-26796",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrivers: perf: ctr_get_width function for legacy is not defined\n\nWith parameters CONFIG_RISCV_PMU_LEGACY=y and CONFIG_RISCV_PMU_SBI=n\nlinux kernel crashes when you try perf record:\n\n$ perf record ls\n[ 46.749286] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000\n[ 46.750199] Oops [#1]\n[ 46.750342] Modules linked in:\n[ 46.750608] CPU: 0 PID: 107 Comm: perf-exec Not tainted 6.6.0 #2\n[ 46.750906] Hardware name: riscv-virtio,qemu (DT)\n[ 46.751184] epc : 0x0\n[ 46.751430] ra : arch_perf_update_userpage+0x54/0x13e\n[ 46.751680] epc : 0000000000000000 ra : ffffffff8072ee52 sp : ff2000000022b8f0\n[ 46.751958] gp : ffffffff81505988 tp : ff6000000290d400 t0 : ff2000000022b9c0\n[ 46.752229] t1 : 0000000000000001 t2 : 0000000000000003 s0 : ff2000000022b930\n[ 46.752451] s1 : ff600000028fb000 a0 : 0000000000000000 a1 : ff600000028fb000\n[ 46.752673] a2 : 0000000ae2751268 a3 : 00000000004fb708 a4 : 0000000000000004\n[ 46.752895] a5 : 0000000000000000 a6 : 000000000017ffe3 a7 : 00000000000000d2\n[ 46.753117] s2 : ff600000028fb000 s3 : 0000000ae2751268 s4 : 0000000000000000\n[ 46.753338] s5 : ffffffff8153e290 s6 : ff600000863b9000 s7 : ff60000002961078\n[ 46.753562] s8 : ff60000002961048 s9 : ff60000002961058 s10: 0000000000000001\n[ 46.753783] s11: 0000000000000018 t3 : ffffffffffffffff t4 : ffffffffffffffff\n[ 46.754005] t5 : ff6000000292270c t6 : ff2000000022bb30\n[ 46.754179] status: 0000000200000100 badaddr: 0000000000000000 cause: 000000000000000c\n[ 46.754653] Code: Unable to access instruction at 0xffffffffffffffec.\n[ 46.754939] ---[ end trace 0000000000000000 ]---\n[ 46.755131] note: perf-exec[107] exited with irqs disabled\n[ 46.755546] note: perf-exec[107] exited with preempt_count 4\n\nThis happens because in the legacy case the ctr_get_width function was not\ndefined, but it is used in arch_perf_update_userpage.\n\nAlso remove extra check in riscv_pmu_ctr_get_width_mask"
            }
        ]
    },
    "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": "cc4c07c89aad",
                                            "version_value": "e0d17ee872cf"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.6",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "6.6",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.6.21",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.7.9",
                                                        "lessThanOrEqual": "6.7.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.8",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/e0d17ee872cf8d0f51cc561329b8e1a0aa792bbb",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/e0d17ee872cf8d0f51cc561329b8e1a0aa792bbb"
            },
            {
                "url": "https://git.kernel.org/stable/c/e4f50e85de5a6b21dfdc0d7ca435eba4f62935c3",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/e4f50e85de5a6b21dfdc0d7ca435eba4f62935c3"
            },
            {
                "url": "https://git.kernel.org/stable/c/682dc133f83e0194796e6ea72eb642df1c03dfbe",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/682dc133f83e0194796e6ea72eb642df1c03dfbe"
            }
        ]
    },
    "generator": {
        "engine": "bippy-9e1c9544281a"
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}