diff --git a/src/ld_so/linker.rs b/src/ld_so/linker.rs index 118122f6bcc7d5afefc9315309be8a54d510ae6d..8fc7bc876b8513c9d3756043b92ab2e95ba0ad67 100644 --- a/src/ld_so/linker.rs +++ b/src/ld_so/linker.rs @@ -689,29 +689,36 @@ impl Linker { } } - // overwrite DT_DEBUG if exist in .dynamic section - for section in &elf.section_headers { - // we won't bother with half corrupted elfs. - let name = elf.shdr_strtab.get(section.sh_name).unwrap().unwrap(); - if name != ".dynamic" { - continue; + // overwrite DT_DEBUG if exist in DYNAMIC segment + // first we identify the location of DYNAMIC segment + let mut dyn_start = None; + let mut debug_start = None; + for ph in elf.program_headers.iter() { + if ph.p_type == program_header::PT_DYNAMIC { + dyn_start = Some(ph.p_vaddr as usize); } - let mmap = match self.mmaps.get_mut(*elf_name) { - Some(some) => some, - None => continue, - }; - let dyn_start = section.sh_addr as usize; - let bytes: [u8; size_of::<Dyn>() / 2] = - unsafe { transmute((&_r_debug) as *const RTLDDebug as usize) }; - if let Some(dynamic) = elf.dynamic.as_ref() { - let mut i = 0; - for entry in &dynamic.dyns { - if entry.d_tag == DT_DEBUG { - let start = dyn_start + i * size_of::<Dyn>() + size_of::<Dyn>() / 2; - mmap[start..start + size_of::<Dyn>() / 2].clone_from_slice(&bytes); - } - i += 1; + } + // next we identify the location of DT_DEBUG in .dynamic section + if let Some(dynamic) = elf.dynamic.as_ref() { + let mut i = 0; + for entry in &dynamic.dyns { + if entry.d_tag == DT_DEBUG { + debug_start = Some(i as usize); + break; } + i += 1; + } + } + if let Some(dyn_start_addr) = dyn_start { + if let Some(i) = debug_start { + let mmap = match self.mmaps.get_mut(*elf_name) { + Some(some) => some, + None => continue, + }; + let bytes: [u8; size_of::<Dyn>() / 2] = + unsafe { transmute((&_r_debug) as *const RTLDDebug as usize) }; + let start = dyn_start_addr + i * size_of::<Dyn>() + size_of::<Dyn>() / 2; + mmap[start..start + size_of::<Dyn>() / 2].clone_from_slice(&bytes); } }