_bfd_elf_link_renumber_dynsyms is called twice by the linker. The
first call in bfd_elf_size_dynamic_sections is just to answer the
question as to whether there are there any dynamic symbols. The
second call in bfd_elf_size_dynsym_hash_dynstr sets the st_shndx value
that dynamic symbols will have. strip_excluded_output_sections is
called between these two calls. So sections seen on the first
_bfd_elf_link_renumber_dynsyms pass might differ from those seen on
the second pass. Unfortunately, that can result in a stripped
section's dynamic symbol being assigned a dynindx on the first pass
but not corrected to the final value (of zero, ie. not dynamic) on the
second pass. PowerPC, x86, mips, and most other targets that emit
dynamic section symbols, just test that section symbol dynindx is
non-zero before using a given section symbol in dynamic relocations.
This patch prevents _bfd_elf_link_renumber_dynsyms from setting any
section symbol dynindx on the first pass.
PR 22626
* elflink.c (_bfd_elf_link_renumber_dynsyms): Don't set section
dynindx when section_sym_count is NULL.
(bfd_elf_size_dynamic_sections): Pass NULL section_sym_count to
preliminary _bfd_elf_link_renumber_dynsyms call.
PR 22571
* archive.c (bfd_openr_next_archived_file): Extend the
documentation to note that it is necessary to call
bfd_check_format on the rrturned bfd before using it.
R_AARCH64_ABS64, R_AARCH64_ABS32 and R_AARCH64_ABS16 are data relocations
supported in AArch64 elf ABI.
R_AARCH64_ABS64 under LP64 is allowed in shared object and a dynamic relocation entry
will be generated. This allows the dynamic linker to do further symbol resolution.
R_AARCH64_ABS32 likewise is allowed in shared object, however under ILP32 abi.
The original behavior for R_AARCH64_ABS32 under LP64 is that, it's allowed
in shared object and silently resolved at static linking time.
No dynamic relocation entry is generate for it.
R_AARCH64_ABS16 is allowed in shared object under both L64 and ILP32.
It's resolved at static linking time as well.
Under LP64, the address should be 64-bit. R_AARCH64_ABS32 relocation indicates
an address that is only sized 32 bits which is meaningless in LP64 shared object.
It's useful to error out.
I have checked glibc dynamic linker code, R_AARCH64_ABS16 is not supported at all. So
R_AARCH64_ABS16 should be reject in shared object completely.
In this patch, R_AARCH64_ABS32 is rejected under LP64 in constant section of shared object.
R_AARCH64_ABS16 is rejected in constant section of shared object in both ABI.
This will sometimes provide useful information for buggy code.
This fixes these failures on 64 bit which currently occur when running
the Binutils testsuite with a default PIE compiler.
< FAIL: Build rdynamic-1
< FAIL: Build dynamic-1
< FAIL: Build pr22269-1
bfd/ChangeLog:
2017-12-13 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* elf64-s390.c (elf_s390_adjust_dynamic_symbol): Use
UNDEFWEAK_NO_DYNAMIC_RELOC.
(allocate_dynrelocs): Likewise.
(elf_s390_relocate_section): Check resolved_to_zero.
(elf_s390_finish_dynamic_symbol): Don't generate runtime reloc if
UNDEFWEAK_NO_DYNAMIC_RELOC.
A recent Fedora bug (1520805) exposed a problem with objcopy's reloc
copying code, when a binary also contains mergeable notes. The note
merging code would delete some relocs, but then the reloc copying code
would try to put them back again, which did not work.
So I am checking in the patch below to fix the problem. The patch
also tweaks one of the binutils note merging tests so that it is
skipped for the Sparc64 target, since this has funky relocs.
binutils * objcopy.c (copy_relocations_in_section): Use the orelocations
field of the input section, if it has been initialised.
* testsuite/binutils-all/note-2-64.d: Skip test on Sparc64.
bfd * elfcode.h (elf_write_relocs): Check for an empty howto field.
Many targets define their own dyn_relocs struct when they could use
struct elf_dyn_relocs. This patch tidies that, and uses
readonly_dynrelocs in a few more places.
The SH adjust_dynamic_symbol had some really weird code dating back to
2002 that looked over dynamic relocations for any in SEC_HAS_CONTENTS
or SEC_READONLY sections, rather than just the usual SEC_READONLY
sections. So basically any dynamic relocation. What's more, the SH
relocate_section has no support for emitting dynamic relocations in
non-PIC. In other words, SH has no support for avoiding copy relocs
in non-PIC. I've made that more obvious by using "if (0 && ..)" in
asjust_dynamic_symbol.
Unfortunately, LM32, M32R, NDS32, and OR1K copied the bogus SH
adjust_dynamic_symbol code. So none of those targets would have
avoided copy relocs. LM32, M32R, NDS32 get the "if (0)" treatment
too. (LM32 is even more broken in that non_got_ref is never set.)
OR1K relocate_section looks like it might support dynamic relocs in
non-PIC, so I've enabled the copy reloc avoidance code for that
target.
* elf32-hppa.c (struct elf32_hppa_dyn_reloc_entry): Delete. Use
struct elf_dyn_relocs throughout file instead.
(elf32_hppa_adjust_dynamic_symbol): Comment tidy.
* elf32-lm32.c (struct elf_lm32_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(lm32_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-m32r.c (struct elf_m32r_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(m32r_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-metag.c (struct elf_metag_dyn_reloc_entry): Delete. Use
struct elf_dyn_relocs throughout file instead.
(elf_metag_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf32-microblaze.c (struct elf32_mb_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(readonly_dynrelocs): New function.
(microblaze_elf_adjust_dynamic_symbol): Use it.
* elf32-nds32.c (struct elf_nds32_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(nds32_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-nios2.c (struct elf32_nios2_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
* elf32-or1k.c (struct elf_or1k_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(or1k_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf32-sh.c (struct elf_sh_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(sh_elf_adjust_dynamic_symbol): Use readonly_dynrelocs, but disable.
Disable -z no-copyreloc too.
* elf32-tilepro.c (struct tilepro_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(tilepro_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elfnn-riscv.c (struct riscv_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(riscv_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elfxx-sparc.c (struct _bfd_sparc_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(_bfd_sparc_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elfxx-tilegx.c (struct tilegx_elf_dyn_relocs): Delete. Use
struct elf_dyn_relocs throughout file instead.
(tilegx_elf_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf32-s390.c (elf_s390_adjust_dynamic_symbol): Use readonly_dynrelocs.
* elf64-s390.c (elf_s390_adjust_dynamic_symbol): Use readonly_dynrelocs.
Past tense is wrong for a comment before some action.
* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol): Comment tidy.
* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol): Likewise.
* elfnn-aarch64.c (elfNN_aarch64_adjust_dynamic_symbol): Likewise.
In early October, HJ Lu added support for a number of targets to "Dump
dynamic relocation in read-only section with minfo". This extends
that support to more targets, displays the symbol involved, and splits
the existing function that sets TEXTREL into a "readonly_dynrelocs"
and "maybe_set_textrel" function. I'll need "readonly_dynrelocs" if I
ever get around to fixing "pr22374 function pointer initialization"
fails.
am33_2.0, arc, bfin, hppa64, mn10300, and nios2 fail to mark a binary
needing text relocations with DT_TEXTREL. That's not good. xtensa also
fails to do so but complains about "dangerous relocation: dynamic
relocation in read-only section" so I reckon that is fine and have
marked the test as an xfail. The other targets need maintainer
attention.
Curiously, the map file dump wasn't added for x86, so the map test
currently fail on x86. It also fails on alpha, am33_2.0, arc, bfin,
hppa64, ia64, m68k, mips, mn10300, nios2, score and vax. cris
complains with "tmpdir/textrel.o, section .rodata: relocation
R_CRIS_32 should not be used in a shared object; recompile with -fPIC"
so I've marked it as an xfail.
bfd/
* elf32-hppa.c (maybe_set_textrel): Print symbol for map file output.
* elf32-ppc.c (maybe_set_textrel): Likewise.
* elf64-ppc.c (maybe_set_textrel): Likewise.
* elf32-arm.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing..
(elf32_arm_readonly_dynrelocs): ..this.
* elf32-lm32.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-m32r.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-metag.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-nds32.c: Delete unnecessary forward declarations.
(readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-or1k.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-s390.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-sh.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf32-tic6x.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing..
(elf32_tic6x_readonly_dynrelocs): ..this.
* elf32-tilepro.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elf64-s390.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elfnn-aarch64.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing..
(aarch64_readonly_readonly_dynrelocs): ..this.
* elfnn-riscv.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elfxx-sparc.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
* elfxx-tilegx.c (readonly_dynrelocs): New function.
(maybe_set_textrel): New function, replacing old version of..
(readonly_dynrelocs): ..this.
ld/
* testsuite/ld-elf/shared.exp: Run new textrel tests.
* testsuite/ld-elf/textrel.map: New file.
* testsuite/ld-elf/textrel.rd: New file.
* testsuite/ld-elf/textrel.s: New file.
* testsuite/ld-elf/textrel.warn: New file.