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| author | H.J. Lu <hjl.tools@gmail.com> | 2018-05-14 03:55:37 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2018-05-14 03:55:50 -0700 |
| commit | 4ec0995016801cc5d5cf13baf6e10163861e6852 (patch) | |
| tree | f2aa11725ad03aec8080cb88b6415c7fcdf2098f /bfd/elfxx-x86.c | |
| parent | 9bc935ef3380a2d471b9447e2bf8e61297654e2f (diff) | |
| download | gdb-4ec0995016801cc5d5cf13baf6e10163861e6852.zip gdb-4ec0995016801cc5d5cf13baf6e10163861e6852.tar.gz gdb-4ec0995016801cc5d5cf13baf6e10163861e6852.tar.bz2 | |
x86; Allow IFUNC pointer defined in PDE
If IFUNC symbol is defined in position-dependent executable, we should
change it to the normal function and set its address to its PLT entry
which should be resolved by R_*_IRELATIVE at run-time. All external
references should be resolved to its PLT in executable.
bfd/
PR ld/23169
* elf-ifunc.c (_bfd_elf_allocate_ifunc_dyn_relocs): Don't issue
an error on IFUNC pointer defined in PDE.
* elf32-i386.c (elf_i386_finish_dynamic_symbol): Call
_bfd_x86_elf_link_fixup_ifunc_symbol.
* elf64-x86-64.c (elf_x86_64_finish_dynamic_symbol): Likewise.
* elfxx-x86.c (_bfd_x86_elf_link_fixup_ifunc_symbol): New
function.
* elfxx-x86.h (_bfd_x86_elf_link_fixup_ifunc_symbol): New.
ld/
PR ld/23169
* testsuite/ld-ifunc/ifunc-9-i386.d: New file.
* testsuite/ld-ifunc/ifunc-9-x86-64.d: Likewise.
* testsuite/ld-ifunc/pr23169a.c: Likewise.
* testsuite/ld-ifunc/pr23169a.rd: Likewise.
* testsuite/ld-ifunc/pr23169b.c: Likewise.
* testsuite/ld-ifunc/pr23169b.c: Likewise.
* testsuite/ld-ifunc/pr23169c.rd: Likewise.
* testsuite/ld-ifunc/pr23169c.rd: Likewise.
* testsuite/ld-ifunc/ifunc-9-x86.d: Removed.
* testsuite/ld-ifunc/ifunc.exp: Run PR ld/23169 tests.
Diffstat (limited to 'bfd/elfxx-x86.c')
| -rw-r--r-- | bfd/elfxx-x86.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/bfd/elfxx-x86.c b/bfd/elfxx-x86.c index 6c1f4c3..936b4c6 100644 --- a/bfd/elfxx-x86.c +++ b/bfd/elfxx-x86.c @@ -1730,6 +1730,52 @@ _bfd_x86_elf_fixup_symbol (struct bfd_link_info *info, return TRUE; } +/* Change the STT_GNU_IFUNC symbol defined in position-dependent + executable into the normal function symbol and set its address + to its PLT entry, which should be resolved by R_*_IRELATIVE at + run-time. */ + +void +_bfd_x86_elf_link_fixup_ifunc_symbol (struct bfd_link_info *info, + struct elf_x86_link_hash_table *htab, + struct elf_link_hash_entry *h, + Elf_Internal_Sym *sym) +{ + if (bfd_link_pde (info) + && h->def_regular + && h->dynindx != -1 + && h->plt.offset != (bfd_vma) -1 + && h->type == STT_GNU_IFUNC + && h->pointer_equality_needed) + { + asection *plt_s; + bfd_vma plt_offset; + bfd *output_bfd = info->output_bfd; + + if (htab->plt_second) + { + struct elf_x86_link_hash_entry *eh + = (struct elf_x86_link_hash_entry *) h; + + plt_s = htab->plt_second; + plt_offset = eh->plt_second.offset; + } + else + { + plt_s = htab->elf.splt; + plt_offset = h->plt.offset; + } + + sym->st_size = 0; + sym->st_info = ELF_ST_INFO (ELF_ST_BIND (sym->st_info), STT_FUNC); + sym->st_shndx + = _bfd_elf_section_from_bfd_section (output_bfd, + plt_s->output_section); + sym->st_value = (plt_s->output_section->vma + + plt_s->output_offset + plt_offset); + } +} + /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */ bfd_boolean |