symbols_map: allow unexpected EOF in ELF files
Some of the prebuilt ELF files used for bionic heads cause an
unexpected EOF error, ignore unexpected EOF the same way we do
for EOF.
Test: not yet
Change-Id: I267d11b4d12b83ecebedc72a565e148c5e53af6d
diff --git a/cmd/symbols_map/elf.go b/cmd/symbols_map/elf.go
index 3c8b1e4..950e3b2 100644
--- a/cmd/symbols_map/elf.go
+++ b/cmd/symbols_map/elf.go
@@ -38,13 +38,13 @@
return elfIdentifierFromReaderAt(f, filename, allowMissing)
}
-// elfIdentifier extracts the elf build ID from a ReaderAt. If allowMissing is true it returns
-// an empty identifier if the file exists but the build ID note does not.
+// elfIdentifierFromReaderAt extracts the elf build ID from a ReaderAt. If allowMissing is true it
+// returns an empty identifier if the file exists but the build ID note does not.
func elfIdentifierFromReaderAt(r io.ReaderAt, filename string, allowMissing bool) (string, error) {
f, err := elf.NewFile(r)
if err != nil {
if allowMissing {
- if errors.Is(err, io.EOF) {
+ if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {
return "", nil
}
if _, ok := err.(*elf.FormatError); ok {
diff --git a/cmd/symbols_map/elf_test.go b/cmd/symbols_map/elf_test.go
index b96ea59..a94c87f 100644
--- a/cmd/symbols_map/elf_test.go
+++ b/cmd/symbols_map/elf_test.go
@@ -39,6 +39,10 @@
name: "empty elf",
contents: emptyElfFile(),
},
+ {
+ name: "short section header",
+ contents: shortSectionHeaderElfFile(),
+ },
}
for _, tt := range tests {
@@ -111,3 +115,38 @@
binary.Write(buf, binary.LittleEndian, header)
return buf.String()
}
+
+// shortSectionHeader returns an elf file header with a section header that extends past the end of
+// the file.
+func shortSectionHeaderElfFile() string {
+ ident := [elf.EI_NIDENT]byte{}
+ identBuf := bytes.NewBuffer(ident[0:0:elf.EI_NIDENT])
+ binary.Write(identBuf, binary.LittleEndian, []byte("\x7fELF"))
+ binary.Write(identBuf, binary.LittleEndian, elf.ELFCLASS64)
+ binary.Write(identBuf, binary.LittleEndian, elf.ELFDATA2LSB)
+ binary.Write(identBuf, binary.LittleEndian, elf.EV_CURRENT)
+ binary.Write(identBuf, binary.LittleEndian, elf.ELFOSABI_LINUX)
+ binary.Write(identBuf, binary.LittleEndian, make([]byte, 8))
+
+ header := elf.Header64{
+ Ident: ident,
+ Type: uint16(elf.ET_EXEC),
+ Machine: uint16(elf.EM_X86_64),
+ Version: uint32(elf.EV_CURRENT),
+ Entry: 0,
+ Phoff: uint64(binary.Size(elf.Header64{})),
+ Shoff: uint64(binary.Size(elf.Header64{})),
+ Flags: 0,
+ Ehsize: uint16(binary.Size(elf.Header64{})),
+ Phentsize: 0x38,
+ Phnum: 0,
+ Shentsize: 0x40,
+ Shnum: 1,
+ Shstrndx: 0,
+ }
+
+ buf := &bytes.Buffer{}
+ binary.Write(buf, binary.LittleEndian, header)
+ binary.Write(buf, binary.LittleEndian, []byte{0})
+ return buf.String()
+}
