From 76689845e331d32c94d77280c34fb92e7dde79ba Mon Sep 17 00:00:00 2001 From: Joel Sing Date: Thu, 15 Nov 2012 02:24:14 +1100 Subject: debug/elf: do not skip first symbol in the symbol table Do not skip the first symbol in the symbol table. Any other indexes into the symbol table (for example, indexes in relocation entries) will now refer to the symbol following the one that was intended. Add an object that contains debug relocations, which debug/dwarf failed to decode correctly. Extend the relocation tests to cover this case. Note that the existing tests passed since the symbol following the symbol that required relocation is also of type STT_SECTION. Fixes #4107. R=golang-dev, mikioh.mikioh, iant, iant CC=golang-dev https://golang.org/cl/6848044 --- src/pkg/debug/elf/file.go | 8 --- src/pkg/debug/elf/file_test.go | 60 ++++++++++++++------- .../testdata/gcc-amd64-openbsd-debug-with-rela.obj | Bin 0 -> 6544 bytes 3 files changed, 41 insertions(+), 27 deletions(-) create mode 100644 src/pkg/debug/elf/testdata/gcc-amd64-openbsd-debug-with-rela.obj (limited to 'src/pkg/debug') diff --git a/src/pkg/debug/elf/file.go b/src/pkg/debug/elf/file.go index d38da4bf8e..25b04d7959 100644 --- a/src/pkg/debug/elf/file.go +++ b/src/pkg/debug/elf/file.go @@ -417,10 +417,6 @@ func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) { return nil, nil, errors.New("cannot load string table section") } - // The first entry is all zeros. - var skip [Sym32Size]byte - symtab.Read(skip[0:]) - symbols := make([]Symbol, symtab.Len()/Sym32Size) i := 0 @@ -460,10 +456,6 @@ func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) { return nil, nil, errors.New("cannot load string table section") } - // The first entry is all zeros. - var skip [Sym64Size]byte - symtab.Read(skip[0:]) - symbols := make([]Symbol, symtab.Len()/Sym64Size) i := 0 diff --git a/src/pkg/debug/elf/file_test.go b/src/pkg/debug/elf/file_test.go index 12036e816b..810a2f9b9a 100644 --- a/src/pkg/debug/elf/file_test.go +++ b/src/pkg/debug/elf/file_test.go @@ -175,23 +175,41 @@ func TestOpen(t *testing.T) { } } +type relocationTestEntry struct { + entryNumber int + entry *dwarf.Entry +} + type relocationTest struct { - file string - firstEntry *dwarf.Entry + file string + entries []relocationTestEntry } var relocationTests = []relocationTest{ { "testdata/go-relocation-test-gcc441-x86-64.obj", - &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}, + []relocationTestEntry{ + {0, &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}}, + }, }, { "testdata/go-relocation-test-gcc441-x86.obj", - &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "t.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x5)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}, + []relocationTestEntry{ + {0, &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "t.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x5)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}}, + }, }, { "testdata/go-relocation-test-gcc424-x86-64.obj", - &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.2.4 (Ubuntu 4.2.4-1ubuntu4)"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test-gcc424.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}, + []relocationTestEntry{ + {0, &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.2.4 (Ubuntu 4.2.4-1ubuntu4)"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test-gcc424.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}}, + }, + }, + { + "testdata/gcc-amd64-openbsd-debug-with-rela.obj", + []relocationTestEntry{ + {203, &dwarf.Entry{Offset: 0xc62, Tag: dwarf.TagMember, Children: false, Field: []dwarf.Field{{Attr: dwarf.AttrName, Val: "it_interval"}, {Attr: dwarf.AttrDeclFile, Val: int64(7)}, {Attr: dwarf.AttrDeclLine, Val: int64(236)}, {Attr: dwarf.AttrType, Val: dwarf.Offset(0xb7f)}, {Attr: dwarf.AttrDataMemberLoc, Val: []byte{0x23, 0x0}}}}}, + {204, &dwarf.Entry{Offset: 0xc70, Tag: dwarf.TagMember, Children: false, Field: []dwarf.Field{{Attr: dwarf.AttrName, Val: "it_value"}, {Attr: dwarf.AttrDeclFile, Val: int64(7)}, {Attr: dwarf.AttrDeclLine, Val: int64(237)}, {Attr: dwarf.AttrType, Val: dwarf.Offset(0xb7f)}, {Attr: dwarf.AttrDataMemberLoc, Val: []byte{0x23, 0x10}}}}}, + }, }, } @@ -207,20 +225,24 @@ func TestDWARFRelocations(t *testing.T) { t.Error(err) continue } - reader := dwarf.Reader() - // Checking only the first entry is sufficient since it has - // many different strings. If the relocation had failed, all - // the string offsets would be zero and all the strings would - // end up being the same. - firstEntry, err := reader.Next() - if err != nil { - t.Error(err) - continue - } - - if !reflect.DeepEqual(test.firstEntry, firstEntry) { - t.Errorf("#%d: mismatch: got:%#v want:%#v", i, firstEntry, test.firstEntry) - continue + for _, testEntry := range test.entries { + reader := dwarf.Reader() + for j := 0; j < testEntry.entryNumber; j++ { + entry, err := reader.Next() + if entry == nil || err != nil { + t.Errorf("Failed to skip to entry %d: %v", testEntry.entryNumber, err) + continue + } + } + entry, err := reader.Next() + if err != nil { + t.Error(err) + continue + } + if !reflect.DeepEqual(testEntry.entry, entry) { + t.Errorf("#%d/%d: mismatch: got:%#v want:%#v", i, testEntry.entryNumber, entry, testEntry.entry) + continue + } } } } diff --git a/src/pkg/debug/elf/testdata/gcc-amd64-openbsd-debug-with-rela.obj b/src/pkg/debug/elf/testdata/gcc-amd64-openbsd-debug-with-rela.obj new file mode 100644 index 0000000000..f62b1ea1ca Binary files /dev/null and b/src/pkg/debug/elf/testdata/gcc-amd64-openbsd-debug-with-rela.obj differ -- cgit v1.3