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| author | H.J. Lu <hjl.tools@gmail.com> | 2022-01-04 05:47:21 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2022-04-26 10:16:11 -0700 |
| commit | 60196d2ef2850f222c7c93818ccb4d9cdbd77276 (patch) | |
| tree | 2e2d678662bc8bcd7aa9075505dd8c792cdde348 | |
| parent | e895cff59aa562cad83fa0fdd187bfe4b45312d5 (diff) | |
| download | glibc-60196d2ef2850f222c7c93818ccb4d9cdbd77276.zip glibc-60196d2ef2850f222c7c93818ccb4d9cdbd77276.tar.gz glibc-60196d2ef2850f222c7c93818ccb4d9cdbd77276.tar.bz2 | |
elf: Properly handle zero DT_RELA/DT_REL values
With DT_RELR, there may be no relocations in DT_RELA/DT_REL and their
entry values are zero. Don't relocate DT_RELA/DT_REL and update the
combined relocation start address if their entry values are zero.
| -rw-r--r-- | elf/dynamic-link.h | 6 | ||||
| -rw-r--r-- | elf/get-dynamic-info.h | 24 |
2 files changed, 23 insertions, 7 deletions
diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h index 019088f..debbb8c 100644 --- a/elf/dynamic-link.h +++ b/elf/dynamic-link.h @@ -84,7 +84,9 @@ elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[], __typeof (((ElfW(Dyn) *) 0)->d_un.d_val) nrelative; int lazy; } \ ranges[2] = { { 0, 0, 0, 0 }, { 0, 0, 0, 0 } }; \ \ - if ((map)->l_info[DT_##RELOC]) \ + /* With DT_RELR, DT_RELA/DT_REL can have zero value. */ \ + if ((map)->l_info[DT_##RELOC] != NULL \ + && (map)->l_info[DT_##RELOC]->d_un.d_ptr != 0) \ { \ ranges[0].start = D_PTR ((map), l_info[DT_##RELOC]); \ ranges[0].size = (map)->l_info[DT_##RELOC##SZ]->d_un.d_val; \ @@ -98,6 +100,8 @@ elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[], ElfW(Addr) start = D_PTR ((map), l_info[DT_JMPREL]); \ ElfW(Addr) size = (map)->l_info[DT_PLTRELSZ]->d_un.d_val; \ \ + if (ranges[0].start == 0) \ + ranges[0].start = start; \ if (ranges[0].start + ranges[0].size == (start + size)) \ ranges[0].size -= size; \ if (!(do_lazy) \ diff --git a/elf/get-dynamic-info.h b/elf/get-dynamic-info.h index 6c2a3a1..0314baf 100644 --- a/elf/get-dynamic-info.h +++ b/elf/get-dynamic-info.h @@ -75,24 +75,36 @@ elf_get_dynamic_info (struct link_map *l, bool bootstrap, # define ADJUST_DYN_INFO(tag) \ do \ - if (info[tag] != NULL) \ - info[tag]->d_un.d_ptr += l_addr; \ + { \ + if (info[tag] != NULL) \ + info[tag]->d_un.d_ptr += l_addr; \ + } \ while (0) ADJUST_DYN_INFO (DT_HASH); ADJUST_DYN_INFO (DT_PLTGOT); ADJUST_DYN_INFO (DT_STRTAB); ADJUST_DYN_INFO (DT_SYMTAB); + ADJUST_DYN_INFO (DT_RELR); + ADJUST_DYN_INFO (DT_JMPREL); + ADJUST_DYN_INFO (VERSYMIDX (DT_VERSYM)); + ADJUST_DYN_INFO (ADDRIDX (DT_GNU_HASH)); +# undef ADJUST_DYN_INFO + + /* DT_RELA/DT_REL are mandatory. But they may have zero value if + there is DT_RELR. Don't relocate them if they are zero. */ +# define ADJUST_DYN_INFO(tag) \ + do \ + if (info[tag] != NULL && info[tag]->d_un.d_ptr != 0) \ + info[tag]->d_un.d_ptr += l_addr; \ + while (0) + # if ! ELF_MACHINE_NO_RELA ADJUST_DYN_INFO (DT_RELA); # endif # if ! ELF_MACHINE_NO_REL ADJUST_DYN_INFO (DT_REL); # endif - ADJUST_DYN_INFO (DT_RELR); - ADJUST_DYN_INFO (DT_JMPREL); - ADJUST_DYN_INFO (VERSYMIDX (DT_VERSYM)); - ADJUST_DYN_INFO (ADDRIDX (DT_GNU_HASH)); # undef ADJUST_DYN_INFO } if (info[DT_PLTREL] != NULL) |