| Message ID | 20220414232129.1886210-5-hjl.tools@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | Support DT_RELR relative relocation format | expand |
On 14/04/2022 20:21, H.J. Lu wrote: > 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. LGTM, thanks. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> > --- > elf/dynamic-link.h | 6 +++++- > 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 7325e0d9fc..7dd8f1b1d6 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 6c2a3a12b1..0314baf020 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)
diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h index 7325e0d9fc..7dd8f1b1d6 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 6c2a3a12b1..0314baf020 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)