{"record":{"id":"3b006ed551c0d36b","repo":"go-delve/delve","slug":"the-specific-range-has-exceeded-readable-area","errorCode":null,"errorMessage":"the specific range has exceeded readable area","messagePattern":"the specific range has exceeded readable area","errorType":"error_code","errorClass":null,"httpStatus":null,"severity":"error","filePath":"service/debugger/debugger.go","lineNumber":2258,"sourceCode":"\tdefer d.targetMutex.Unlock()\n\treturn d.target.Selected.BinInfo().Images\n}\n\n// ExamineMemory returns the raw memory stored at the given address.\n// The amount of data to be read is specified by length.\n// This function will return an error if it reads less than `length` bytes.\nfunc (d *Debugger) ExamineMemory(address uint64, length int) ([]byte, error) {\n\td.targetMutex.Lock()\n\tdefer d.targetMutex.Unlock()\n\n\tmem := d.target.Selected.Memory()\n\tdata := make([]byte, length)\n\tn, err := mem.ReadMemory(data, address)\n\tif err != nil {\n\t\treturn nil, err\n\t}\n\tif length != n {\n\t\treturn nil, errors.New(\"the specific range has exceeded readable area\")\n\t}\n\treturn data, nil\n}\n\nfunc (d *Debugger) GetVersion(out *api.GetVersionOut) error {\n\tif d.config.CoreFile != \"\" {\n\t\tif d.config.Backend == \"rr\" {\n\t\t\tout.Backend = \"rr\"\n\t\t} else {\n\t\t\tout.Backend = \"core\"\n\t\t}\n\t} else {\n\t\tif d.config.Backend == \"default\" {\n\t\t\tif runtime.GOOS == \"darwin\" {\n\t\t\t\tout.Backend = \"lldb\"\n\t\t\t} else {\n\t\t\t\tout.Backend = \"native\"\n\t\t\t}","sourceCodeStart":2240,"sourceCodeEnd":2276,"githubUrl":"https://github.com/go-delve/delve/blob/a23773e6c31361e43246bc43a424ee009679b174/service/debugger/debugger.go#L2240-L2276","documentation":"This error comes from a helper that reads a fixed-length byte range from the target's memory. The underlying MemoryReadWriter may return fewer bytes than requested even without a hard error (e.g. the range straddles the end of a mapped page). Delve treats a short read as a failure of the requested range and returns this error instead of partial data.","triggerScenarios":"Calling the memory-reading helper (used by ExamineMemory and similar APIs) with an address/length whose range extends beyond the readable mapped region of the debuggee or core file, so mem.ReadMemory returns n < length.","commonSituations":"Examining memory at an address computed from a bad/optimized pointer; reading past the end of a heap allocation or unmapped page; core dump analysis where only some pages are present; hexdump commands with oversized lengths.","solutions":["Reduce the requested length so it stays within one readable mapped region","Verify the base address is valid (check the variable/expression that produced it)","Use ExamineMemory's region info or `/proc/<pid>/maps` to find readable boundaries","Read in smaller chunks and stop at the first short read"],"exampleFix":"// before\nmem, _ := dbg.ExamineMemory(&api.ExamineMemoryIn{Address: 0xC000000000, Length: 0x10000}) // crosses unmapped gap\n// after\nmem, _ := dbg.ExamineMemory(&api.ExamineMemoryIn{Address: 0xC000000000, Length: 0x1000}) // stay within mapped page","handlingStrategy":"validation","validationCode":"func safeReadLength(addr uint64, length int64, maxRegion uint64) (int64, bool) {\n    if addr >= maxRegion || length <= 0 || addr+uint64(length) > maxRegion {\n        return 0, false\n    }\n    return length, true\n}","typeGuard":"func readableRange(addr uint64, length int64) bool {\n    return length > 0 && addr != 0 && addr < ^uint64(0)-uint64(length)\n}","tryCatchPattern":"data, err := dbg.examineMemory(address, length)\nif err != nil && err.Error() == \"the specific range has exceeded readable area\" {\n    // retry with smaller chunk within the mapped region\n}","preventionTips":["Read memory in page-sized chunks and stop at the first short read","Validate pointer values before dereferencing for hexdumps","When reading structs, read only within the known allocation bounds","For core dumps, consult the loaded memory map for present pages"],"tags":["memory","examine-memory","core-dump"],"backgroundTag":"memory-read-out-of-bounds","analyzedSha":"a23773e6c31361e43246bc43a424ee009679b174","analyzedAt":"2026-08-31T15:12:45.221Z","schemaVersion":2},"datasetVersion":"2026-08-31T19:17:28.585Z"}