{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-49888",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix a sdiv overflow issue\n\nZac Ecob reported a problem where a bpf program may cause kernel crash due\nto the following error:\n  Oops: divide error: 0000 [#1] PREEMPT SMP KASAN PTI\n\nThe failure is due to the below signed divide:\n  LLONG_MIN/-1 where LLONG_MIN equals to -9,223,372,036,854,775,808.\nLLONG_MIN/-1 is supposed to give a positive number 9,223,372,036,854,775,808,\nbut it is impossible since for 64-bit system, the maximum positive\nnumber is 9,223,372,036,854,775,807. On x86_64, LLONG_MIN/-1 will\ncause a kernel exception. On arm64, the result for LLONG_MIN/-1 is\nLLONG_MIN.\n\nFurther investigation found all the following sdiv/smod cases may trigger\nan exception when bpf program is running on x86_64 platform:\n  - LLONG_MIN/-1 for 64bit operation\n  - INT_MIN/-1 for 32bit operation\n  - LLONG_MIN%-1 for 64bit operation\n  - INT_MIN%-1 for 32bit operation\nwhere -1 can be an immediate or in a register.\n\nOn arm64, there are no exceptions:\n  - LLONG_MIN/-1 = LLONG_MIN\n  - INT_MIN/-1 = INT_MIN\n  - LLONG_MIN%-1 = 0\n  - INT_MIN%-1 = 0\nwhere -1 can be an immediate or in a register.\n\nInsn patching is needed to handle the above cases and the patched codes\nproduced results aligned with above arm64 result. The below are pseudo\ncodes to handle sdiv/smod exceptions including both divisor -1 and divisor 0\nand the divisor is stored in a register.\n\nsdiv:\n      tmp = rX\n      tmp += 1 /* [-1, 0] -> [0, 1]\n      if tmp >(unsigned) 1 goto L2\n      if tmp == 0 goto L1\n      rY = 0\n  L1:\n      rY = -rY;\n      goto L3\n  L2:\n      rY /= rX\n  L3:\n\nsmod:\n      tmp = rX\n      tmp += 1 /* [-1, 0] -> [0, 1]\n      if tmp >(unsigned) 1 goto L1\n      if tmp == 1 (is64 ? goto L2 : goto L3)\n      rY = 0;\n      goto L2\n  L1:\n      rY %= rX\n  L2:\n      goto L4  // only when !is64\n  L3:\n      wY = wY  // only when !is64\n  L4:\n\n  [1] https://lore.kernel.org/bpf/tPJLTEh7S_DxFEqAI2Ji5MBSoZVg7_G-Py2iaZpAaWtM961fFTWtsnlzwvTbzBzaUzwQAoNATXKUlt0LZOFgnDcIyKCswAnAGdUF3LBrhGQ=@protonmail.com/"
            }
        ]
    },
    "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": "4902a6a0dc59"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.10.14",
                                                        "lessThanOrEqual": "6.10.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.11.3",
                                                        "lessThanOrEqual": "6.11.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.12-rc1",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/4902a6a0dc593c82055fc8c9ada371bafe26c9cc",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/4902a6a0dc593c82055fc8c9ada371bafe26c9cc"
            },
            {
                "url": "https://git.kernel.org/stable/c/d22e45a369afc7c28f11acfa5b5e8e478227ca5d",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/d22e45a369afc7c28f11acfa5b5e8e478227ca5d"
            },
            {
                "url": "https://git.kernel.org/stable/c/7dd34d7b7dcf9309fc6224caf4dd5b35bedddcb7",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/7dd34d7b7dcf9309fc6224caf4dd5b35bedddcb7"
            }
        ]
    },
    "generator": {
        "engine": "bippy-c9c4e1df01b2"
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}