From b413280cfb16834450f66f554bc0d618bb513851 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Thu, 16 Sep 2021 08:15:29 -0700 Subject: ld.so: Replace DL_RO_DYN_SECTION with dl_relocate_ld [BZ #28340] 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 --- elf/get-dynamic-info.h | 21 +++------------------ 1 file changed, 3 insertions(+), 18 deletions(-) (limited to 'elf/get-dynamic-info.h') diff --git a/elf/get-dynamic-info.h b/elf/get-dynamic-info.h index d8ec323..4aa2058 100644 --- a/elf/get-dynamic-info.h +++ b/elf/get-dynamic-info.h @@ -28,7 +28,7 @@ static auto #endif inline void __attribute__ ((unused, always_inline)) -elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp) +elf_get_dynamic_info (struct link_map *l) { #if __ELF_NATIVE_CLASS == 32 typedef Elf32_Word d_tag_utype; @@ -69,28 +69,15 @@ elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp) info[i] = dyn; } -#define DL_RO_DYN_TEMP_CNT 8 - -#ifndef DL_RO_DYN_SECTION /* Don't adjust .dynamic unnecessarily. */ - if (l->l_addr != 0) + if (l->l_addr != 0 && dl_relocate_ld (l)) { ElfW(Addr) l_addr = l->l_addr; - int cnt = 0; # define ADJUST_DYN_INFO(tag) \ do \ if (info[tag] != NULL) \ - { \ - if (temp) \ - { \ - temp[cnt].d_tag = info[tag]->d_tag; \ - temp[cnt].d_un.d_ptr = info[tag]->d_un.d_ptr + l_addr; \ - info[tag] = temp + cnt++; \ - } \ - else \ - info[tag]->d_un.d_ptr += l_addr; \ - } \ + info[tag]->d_un.d_ptr += l_addr; \ while (0) ADJUST_DYN_INFO (DT_HASH); @@ -107,9 +94,7 @@ elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp) ADJUST_DYN_INFO (VERSYMIDX (DT_VERSYM)); ADJUST_DYN_INFO (ADDRIDX (DT_GNU_HASH)); # undef ADJUST_DYN_INFO - assert (cnt <= DL_RO_DYN_TEMP_CNT); } -#endif if (info[DT_PLTREL] != NULL) { #if ELF_MACHINE_NO_RELA -- cgit v1.1