fix(firmware): support special ELF program header with p_filesz=0

Fix #77

src/firmware.rs

@@ -184,7 +184,6 @@ pub fn read_elf(elf_data: &[u8]) -> Result<Firmware> {
     let binary = object::read::elf::ElfFile::<FileHeader32<Endianness>>::parse(elf_data)?;
 
     let mut sections = vec![];
-
     let endian = elf_header.endian()?;
 
     // Ref: https://docs.oracle.com/cd/E19683-01/816-1386/chapter6-83432/index.html
@@ -196,6 +195,11 @@ pub fn read_elf(elf_data: &[u8]) -> Result<Firmware> {
 
         let flags = segment.p_flags(endian);
 
+        // The number of bytes in the file image of the segment, which can be zero.
+        if segment.p_filesz(endian) == 0 {
+            // skip empty segment
+            continue;
+        }
         let segment_data = segment
             .data(endian, elf_data)
             .map_err(|_| anyhow::format_err!("Failed to access data for an ELF segment."))?;