{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-26706",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nparisc: Fix random data corruption from exception handler\n\nThe current exception handler implementation, which assists when accessing\nuser space memory, may exhibit random data corruption if the compiler decides\nto use a different register than the specified register %r29 (defined in\nASM_EXCEPTIONTABLE_REG) for the error code. If the compiler choose another\nregister, the fault handler will nevertheless store -EFAULT into %r29 and thus\ntrash whatever this register is used for.\nLooking at the assembly I found that this happens sometimes in emulate_ldd().\n\nTo solve the issue, the easiest solution would be if it somehow is\npossible to tell the fault handler which register is used to hold the error\ncode. Using %0 or %1 in the inline assembly is not posssible as it will show\nup as e.g. %r29 (with the \"%r\" prefix), which the GNU assembler can not\nconvert to an integer.\n\nThis patch takes another, better and more flexible approach:\nWe extend the __ex_table (which is out of the execution path) by one 32-word.\nIn this word we tell the compiler to insert the assembler instruction\n\"or %r0,%r0,%reg\", where %reg references the register which the compiler\nchoosed for the error return code.\nIn case of an access failure, the fault handler finds the __ex_table entry and\ncan examine the opcode. The used register is encoded in the lowest 5 bits, and\nthe fault handler can then store -EFAULT into this register.\n\nSince we extend the __ex_table to 3 words we can't use the BUILDTIME_TABLE_SORT\nconfig option any longer."
            }
        ]
    },
    "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": "23027309b099"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.1.79",
                                                        "lessThanOrEqual": "6.1.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.6.18",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.7.6",
                                                        "lessThanOrEqual": "6.7.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.8",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/23027309b099ffc4efca5477009a11dccbdae592",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/23027309b099ffc4efca5477009a11dccbdae592"
            },
            {
                "url": "https://git.kernel.org/stable/c/fa69a8063f8b27f3c7434a0d4f464a76a62f24d2",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/fa69a8063f8b27f3c7434a0d4f464a76a62f24d2"
            },
            {
                "url": "https://git.kernel.org/stable/c/ce31d79aa1f13a2345791f84935281a2c194e003",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/ce31d79aa1f13a2345791f84935281a2c194e003"
            },
            {
                "url": "https://git.kernel.org/stable/c/8b1d72395635af45410b66cc4c4ab37a12c4a831",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/8b1d72395635af45410b66cc4c4ab37a12c4a831"
            }
        ]
    },
    "generator": {
        "engine": "bippy-a5840b7849dd"
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}