libdyld: treat pltrel as relocation with implicit addend

This commit is contained in:
Astro 2020-04-25 21:20:35 +02:00
parent 027fc49809
commit 355b746715

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@ -107,7 +107,7 @@ pub struct Library<'a> {
image_sz: usize,
strtab: &'a [u8],
symtab: &'a [Elf32_Sym],
pltrel: &'a [Elf32_Rela],
pltrel: &'a [Elf32_Rel],
hash_bucket: &'a [Elf32_Word],
hash_chain: &'a [Elf32_Word],
arch: Arch,
@ -170,8 +170,8 @@ impl<'a> Library<'a> {
// This is unsafe because it mutates global data (the PLT).
pub unsafe fn rebind(&self, name: &[u8], addr: Elf32_Word) -> Result<(), Error<'a>> {
for rela in self.pltrel.iter() {
let is_rebind_type = match ELF32_R_TYPE(rela.r_info) {
for rel in self.pltrel.iter() {
let is_rebind_type = match ELF32_R_TYPE(rel.r_info) {
R_OR1K_32 | R_OR1K_GLOB_DAT | R_OR1K_JMP_SLOT
if self.arch == Arch::OpenRisc => true,
R_ARM_GLOB_DAT | R_ARM_JUMP_SLOT
@ -182,12 +182,12 @@ impl<'a> Library<'a> {
};
if is_rebind_type {
let sym = self.symtab.get(ELF32_R_SYM(rela.r_info) as usize)
let sym = self.symtab.get(ELF32_R_SYM(rel.r_info) as usize)
.ok_or("symbol out of bounds of symbol table")?;
let sym_name = self.name_starting_at(sym.st_name as usize)?;
if sym_name == name {
self.update_rela(rela, addr)?
self.update_rel(rel, addr)?
}
}
}
@ -404,7 +404,7 @@ impl<'a> Library<'a> {
DT_RELASZ => rela_sz = val / mem::size_of::<Elf32_Rela>(),
DT_RELAENT => rela_ent = val,
DT_JMPREL => pltrel_off = val,
DT_PLTRELSZ => pltrel_sz = val / mem::size_of::<Elf32_Rela>(),
DT_PLTRELSZ => pltrel_sz = val / mem::size_of::<Elf32_Rel>(),
DT_HASH => {
nbucket = *get_ref::<Elf32_Word>(image, val + 0)
.map_err(|()| "cannot read hash bucket count")? as usize;
@ -442,7 +442,7 @@ impl<'a> Library<'a> {
.map_err(|()| "cannot read rel entries")?;
let rela = get_ref_slice::<Elf32_Rela>(image, rela_off, rela_sz)
.map_err(|()| "cannot read rela entries")?;
let pltrel = get_ref_slice::<Elf32_Rela>(image, pltrel_off, pltrel_sz)
let pltrel = get_ref_slice::<Elf32_Rel>(image, pltrel_off, pltrel_sz)
.map_err(|()| "cannot read pltrel entries")?;
let hash = get_ref_slice::<Elf32_Word>(image, hash_off, hash_sz)
.map_err(|()| "cannot read hash entries")?;
@ -470,7 +470,10 @@ impl<'a> Library<'a> {
for r in rela { library.resolve_rela(r, resolve)? }
for r in rel { library.resolve_rel(r, resolve)? }
for r in pltrel { library.resolve_rela(r, resolve)? }
/// TODO: processing of pltrel has been changed from
/// resolve_rela() to resolve_rel(). verify if this is
/// specific to eg. architecture?
for r in pltrel { library.resolve_rel(r, resolve)? }
Ok(library)
}