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Merge branch 'pie' into 'master'

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Fix bugs in handling non pie elfs

See merge request redox-os/relibc!285
This commit is contained in:
Jeremy Soller
2020-06-24 12:33:47 +00:00
parent 547edcc267 5fcf920675
commit 954f010cc1
1 changed files with 65 additions and 15 deletions
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src/ld_so/linker.rs
+65 -15
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@@ -10,6 +10,7 @@ use core::{
};
use goblin::{
elf::{
header::ET_DYN,
program_header,
r#dyn::{Dyn, DT_DEBUG},
reloc, sym, Elf,
@@ -199,7 +200,11 @@ impl Linker {
let value: usize;
if let Some(name_res) = elf.dynstrtab.get(sym.st_name) {
name = name_res?.to_string();
value = mmap.as_ptr() as usize + sym.st_value as usize;
value = if is_pie_enabled(elf) {
mmap.as_ptr() as usize + sym.st_value as usize
} else {
sym.st_value as usize
};
} else {
continue;
}
@@ -256,7 +261,7 @@ impl Linker {
None => return Ok(()),
};
let elf = Elf::parse(self.objects.get(&root.name).unwrap())?;
for section in elf.section_headers {
for section in &elf.section_headers {
let name = match elf.shdr_strtab.get(section.sh_name) {
Some(x) => match x {
Ok(y) => y,
@@ -265,7 +270,11 @@ impl Linker {
_ => continue,
};
if name == ".init_array" {
let addr = mmap.as_ptr() as usize + section.vm_range().start;
let addr = if is_pie_enabled(&elf) {
mmap.as_ptr() as usize + section.vm_range().start
} else {
section.vm_range().start
};
for i in (0..section.sh_size).step_by(8) {
unsafe { call_inits_finis(addr + i as usize) };
}
@@ -287,7 +296,7 @@ impl Linker {
None => return Ok(()),
};
let elf = Elf::parse(self.objects.get(&root.name).unwrap())?;
for section in elf.section_headers {
for section in &elf.section_headers {
let name = match elf.shdr_strtab.get(section.sh_name) {
Some(x) => match x {
Ok(y) => y,
@@ -296,7 +305,11 @@ impl Linker {
_ => continue,
};
if name == ".fini_array" {
let addr = mmap.as_ptr() as usize + section.vm_range().start;
let addr = if is_pie_enabled(&elf) {
mmap.as_ptr() as usize + section.vm_range().start
} else {
section.vm_range().start
};
for i in (0..section.sh_size).step_by(8) {
unsafe { call_inits_finis(addr + i as usize) };
}
@@ -396,7 +409,12 @@ impl Linker {
};
if same_elf {
let addr = dso.as_ref().unwrap().base_addr;
let size = bounds.1;
let size = if is_pie_enabled(&elf) {
bounds.1
} else {
bounds.1 - bounds.0
};
// Fill the gaps i the binary
let mut ranges = Vec::new();
for ph in elf.program_headers.iter() {
@@ -405,7 +423,11 @@ impl Linker {
let vaddr = ph.p_vaddr as usize - voff;
let vsize = ((ph.p_memsz as usize + voff + PAGE_SIZE - 1) / PAGE_SIZE)
* PAGE_SIZE;
ranges.push((vaddr, vsize));
if is_pie_enabled(&elf) {
ranges.push((vaddr, vsize));
} else {
ranges.push((vaddr - addr, vsize));
}
}
}
ranges.sort();
@@ -651,7 +673,11 @@ impl Linker {
(0, 0)
};
let ptr = unsafe { mmap.as_mut_ptr().add(rel.r_offset as usize) };
let ptr = if is_pie_enabled(&elf) {
unsafe { mmap.as_mut_ptr().add(rel.r_offset as usize) }
} else {
rel.r_offset as *mut u8
};
let set_u64 = |value| {
// println!(" set_u64 {:#x}", value);
@@ -717,7 +743,12 @@ impl Linker {
};
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;
let start = if is_pie_enabled(elf) {
dyn_start_addr + i * size_of::<Dyn>() + size_of::<Dyn>() / 2
} else {
dyn_start_addr + i * size_of::<Dyn>() + size_of::<Dyn>() / 2
- mmap.as_mut_ptr() as usize
};
mmap[start..start + size_of::<Dyn>() / 2].clone_from_slice(&bytes);
}
}
@@ -748,7 +779,11 @@ impl Linker {
None => continue,
};
let res = unsafe {
let ptr = mmap.as_mut_ptr().add(vaddr);
let ptr = if is_pie_enabled(elf) {
mmap.as_mut_ptr().add(vaddr)
} else {
vaddr as *const u8
};
if self.verbose {
println!(" prot {:#x}, {:#x}: {:p}, {:#x}", vaddr, vsize, ptr, prot);
}
@@ -780,7 +815,11 @@ impl Linker {
println!("entry {}", elf_name);
}
if Some(*elf_name) == primary_opt {
entry_opt = Some(mmap.as_mut_ptr() as usize + elf.header.e_entry as usize);
if is_pie_enabled(&elf) {
entry_opt = Some(mmap.as_mut_ptr() as usize + elf.header.e_entry as usize);
} else {
entry_opt = Some(elf.header.e_entry as usize);
}
}
// Relocate
@@ -815,7 +854,6 @@ impl Linker {
}
}
}
// Protect pages
for ph in elf.program_headers.iter() {
if let program_header::PT_LOAD = ph.p_type {
@@ -838,7 +876,11 @@ impl Linker {
}
let res = unsafe {
let ptr = mmap.as_mut_ptr().add(vaddr);
let ptr = if is_pie_enabled(&elf) {
mmap.as_mut_ptr().add(vaddr)
} else {
vaddr as *const u8
};
if self.verbose {
println!(" prot {:#x}, {:#x}: {:p}, {:#x}", vaddr, vsize, ptr, prot);
}
@@ -852,12 +894,20 @@ impl Linker {
}
}
unsafe { _r_debug.state = RTLDState::RT_CONSISTENT };
_dl_debug_state();
//_dl_debug_state();
Ok(entry_opt)
}
}
unsafe extern "C" fn call_inits_finis(addr: usize) {
unsafe fn call_inits_finis(addr: usize) {
let func = transmute::<usize, *const Option<extern "C" fn()>>(addr);
(*func).map(|x| x());
}
fn is_pie_enabled(elf: &Elf) -> bool {
if elf.header.e_type == ET_DYN {
true
} else {
false
}
}