{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2022-50778",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-12-24T13:02:21.547Z",
        "datePublished": "2025-12-24T13:06:07.182Z",
        "dateUpdated": "2026-05-11T19:25:21.810Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T19:25:21.810Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfortify: Fix __compiletime_strlen() under UBSAN_BOUNDS_LOCAL\n\nWith CONFIG_FORTIFY=y and CONFIG_UBSAN_LOCAL_BOUNDS=y enabled, we observe\na runtime panic while running Android's Compatibility Test Suite's (CTS)\nandroid.hardware.input.cts.tests. This is stemming from a strlen()\ncall in hidinput_allocate().\n\n__compiletime_strlen() is implemented in terms of __builtin_object_size(),\nthen does an array access to check for NUL-termination. A quirk of\n__builtin_object_size() is that for strings whose values are runtime\ndependent, __builtin_object_size(str, 1 or 0) returns the maximum size\nof possible values when those sizes are determinable at compile time.\nExample:\n\n  static const char *v = \"FOO BAR\";\n  static const char *y = \"FOO BA\";\n  unsigned long x (int z) {\n      // Returns 8, which is:\n      // max(__builtin_object_size(v, 1), __builtin_object_size(y, 1))\n      return __builtin_object_size(z ? v : y, 1);\n  }\n\nSo when FORTIFY_SOURCE is enabled, the current implementation of\n__compiletime_strlen() will try to access beyond the end of y at runtime\nusing the size of v. Mixed with UBSAN_LOCAL_BOUNDS we get a fault.\n\nhidinput_allocate() has a local C string whose value is control flow\ndependent on a switch statement, so __builtin_object_size(str, 1)\nevaluates to the maximum string length, making all other cases fault on\nthe last character check. hidinput_allocate() could be cleaned up to\navoid runtime calls to strlen() since the local variable can only have\nliteral values, so there's no benefit to trying to fortify the strlen\ncall site there.\n\nPerform a __builtin_constant_p() check against index 0 earlier in the\nmacro to filter out the control-flow-dependant case. Add a KUnit test\nfor checking the expected behavioral characteristics of FORTIFY_SOURCE\ninternals."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/fortify-string.h"
                    ],
                    "versions": [
                        {
                            "version": "3009f891bb9f328945ebd5b71e12df7e2467f3dd",
                            "lessThan": "ed42391164e6839a48aaf4c53eefda516835e799",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "3009f891bb9f328945ebd5b71e12df7e2467f3dd",
                            "lessThan": "5d59ad2bfb35fccfe2ad5e8bb8801f6224d3f7d4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "3009f891bb9f328945ebd5b71e12df7e2467f3dd",
                            "lessThan": "d07c0acb4f41cc42a0d97530946965b3e4fa68c1",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/fortify-string.h"
                    ],
                    "versions": [
                        {
                            "version": "5.16",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.16",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.19.17",
                            "lessThanOrEqual": "5.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.0.3",
                            "lessThanOrEqual": "6.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1",
                            "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": "5.16",
                                    "versionEndExcluding": "5.19.17"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.16",
                                    "versionEndExcluding": "6.0.3"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.16",
                                    "versionEndExcluding": "6.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/ed42391164e6839a48aaf4c53eefda516835e799"
                },
                {
                    "url": "https://git.kernel.org/stable/c/5d59ad2bfb35fccfe2ad5e8bb8801f6224d3f7d4"
                },
                {
                    "url": "https://git.kernel.org/stable/c/d07c0acb4f41cc42a0d97530946965b3e4fa68c1"
                }
            ],
            "title": "fortify: Fix __compiletime_strlen() under UBSAN_BOUNDS_LOCAL",
            "x_generator": {
                "engine": "bippy-1.2.0"
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        }
    }
}