lib/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2025-08-08 17:42:12 +03:00
Code Activity

ld.so: Replace DL_RO_DYN_SECTION with dl_relocate_ld [BZ #28340]

Browse Source 
We can't relocate entries in dynamic section if it is readonly:

1. Add a l_ld_readonly field to struct link_map to indicate if dynamic
section is readonly and set it based on p_flags of PT_DYNAMIC segment.
2. Replace DL_RO_DYN_SECTION with dl_relocate_ld to decide if dynamic
section should be relocated.
3. Remove DL_RO_DYN_TEMP_CNT.
4. Don't use a static dynamic section to make readonly dynamic section
in vDSO writable.
5. Remove the temp argument from elf_get_dynamic_info.

This fixes BZ #28340.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
This commit is contained in:
H.J. Lu
2021-09-16 08:15:29 -07:00
parent 4eff749e8f
commit b413280cfb
16 changed files with 198 additions and 41 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
elf/dl-reloc-static-pie.c
View File

@@ -40,7 +40,17 @@ _dl_relocate_static_pie (void)
/* Read our own dynamic section and fill in the info array. */
main_map->l_ld = ((void *) main_map->l_addr + elf_machine_dynamic ());
elf_get_dynamic_info (main_map, NULL);
const ElfW(Phdr) *ph, *phdr = GL(dl_phdr);
size_t phnum = GL(dl_phnum);
for (ph = phdr; ph < &phdr[phnum]; ++ph)
if (ph->p_type == PT_DYNAMIC)
{
main_map->l_ld_readonly = (ph->p_flags & PF_W) == 0;
break;
}
elf_get_dynamic_info (main_map);
# ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
ELF_MACHINE_BEFORE_RTLD_RELOC (main_map->l_info);