{"record":{"id":"066ebd5a4337e31c","repo":"moonD4rk/HackBrowserData","slug":"region-not-found-in-core-dump","errorCode":null,"errorMessage":"region not found in core dump","messagePattern":"region not found in core dump","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"warning","filePath":"masterkey/gcoredump_darwin.go","lineNumber":224,"sourceCode":"\t}\n\treturn regions, nil\n}\n\n// getMallocSmallRegionData returns the Mach-O segment data + vaddr for the given address range.\nfunc getMallocSmallRegionData(f *macho.File, region addressRange) ([]byte, uint64, error) {\n\tfor _, seg := range f.Loads {\n\t\tif s, ok := seg.(*macho.Segment); ok {\n\t\t\tif s.Addr == region.start && s.Addr+s.Memsz == region.end {\n\t\t\t\tdata := make([]byte, s.Filesz)\n\t\t\t\t_, err := s.ReadAt(data, 0)\n\t\t\t\tif err != nil {\n\t\t\t\t\treturn nil, 0, err\n\t\t\t\t}\n\t\t\t\treturn data, s.Addr, nil\n\t\t\t}\n\t\t}\n\t}\n\treturn nil, 0, fmt.Errorf(\"region not found in core dump\")\n}\n\nfunc byteSliceToString(s []byte) string {\n\tfor i, v := range s {\n\t\tif v == 0 {\n\t\t\treturn string(s[:i])\n\t\t}\n\t}\n\treturn string(s)\n}\n","sourceCodeStart":206,"sourceCodeEnd":235,"githubUrl":"https://github.com/moonD4rk/HackBrowserData/blob/0503d04d7a8d0379d060268a74f1b149e5a0aad5/masterkey/gcoredump_darwin.go#L206-L235","documentation":"getMallocSmallRegionData matches each vmmap MALLOC_SMALL region against Mach-O segments in the core dump by exact address (s.Addr == region.start && s.Addr+s.Memsz == region.end). When no segment lines up exactly with the vmmap range, it returns 'region not found in core dump'; scanMasterKeyCandidates silently skips such regions (continue), so this error usually causes missed regions rather than a surfaced failure.","triggerScenarios":"Any mismatch between vmmap-reported region boundaries and the core dump's segment addresses: gcore omitted that region (e.g. with -s flag stripping some memory), vmmap region merged/split differently than the dump segments, or address layout changed between the vmmap call and the gcore dump (ASLR re-read).","commonSituations":"gcore's -s flag or dump limits excluding regions vmmap reports; timing gaps between vmmap and gcore on a live process; macOS versions where segment granularity differs from vmmap line ranges; end-address off-by-one/granularity mismatches.","solutions":["Note this error is swallowed per-region by scanMasterKeyCandidates — check whether ALL regions are being skipped (leads to error 55) or only some.","Loosen the exact-match comparison to interval containment (segment overlaps region) instead of strict start/end equality.","Run vmmap and gcore as close together as possible (or derive regions from the core dump itself) to avoid address-layout drift between the two calls.","Review the gcore flags (-d -s -v): -s may strip data; test dumping without restrictive flags if regions go missing.","Log skipped regions (start/end) to identify whether specific regions systematically fail to map, indicating a format/flag issue."],"exampleFix":"// before\nif s.Addr == region.start && s.Addr+s.Memsz == region.end {\n// after\nif s.Addr <= region.start && s.Addr+s.Memsz >= region.end {\n","handlingStrategy":"retry","validationCode":"out, _ := exec.Command(\"sudo\", \"vmmap\", \"--wide\", pid).Output()\n// verify regions parse and dump immediately after, minimizing layout drift\nif len(out) == 0 {\n    return fmt.Errorf(\"vmmap produced no output\")\n}","typeGuard":null,"tryCatchPattern":"records, err := masterkey.DecryptKeychainRecords()\nif err != nil && strings.Contains(err.Error(), \"no master key candidates\") {\n    // some regions may have been skipped with 'region not found in core dump'; retry promptly or relax segment matching\n}","preventionTips":["Minimize the delay between vmmap and gcore to avoid address-layout drift.","Prefer containment matching over exact start/end equality when mapping regions to segments.","Re-check gcore flags (-s strips data) if regions systematically fail to map.","Log skipped regions to diagnose systematic mapping failures."],"tags":["macos","macho","core-dump","region-mapping"],"backgroundTag":"resource-not-found","analyzedSha":"0503d04d7a8d0379d060268a74f1b149e5a0aad5","analyzedAt":"2026-09-06T13:38:28.707Z","contentChangedAt":"2026-09-06T13:38:28.707Z","schemaVersion":2},"datasetVersion":"2026-09-14T00:17:10.932Z"}