netconsole: avoid OOB reads, msg is not nul-terminated

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/netconsole.c"
                    ],
                    "versions": [
                        {
                            "version": "c62c0a17f9b7398022f9eebe547878033264f81f",
                            "lessThan": "68fe91df6ea822dae772fceaad0686e4f5839aec",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c62c0a17f9b7398022f9eebe547878033264f81f",
                            "lessThan": "8fe132c4873f9eb1b86ddbf31216e9d961a0b8b9",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c62c0a17f9b7398022f9eebe547878033264f81f",
                            "lessThan": "3126a2f98beaec5a554a1fb31c46db1e8542665e",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c62c0a17f9b7398022f9eebe547878033264f81f",
                            "lessThan": "74ab1456eaa3b2eb986138f9e1f4cb37e73b6f58",
                            "status": "affected",
                            "versionType": "git"
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                        {
                            "version": "c62c0a17f9b7398022f9eebe547878033264f81f",
                            "lessThan": "82aec772fca2223bc5774bd9af486fd95766e578",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                }

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/netconsole.c"
                    ],
                    "versions": [
                        {
                            "version": "6.6",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.6",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.160",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.103",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.16",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19.6",
                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }