save_res stubs aren't written in ppc_build_one_stub, their offsets
(which are zero) should not be checked.
* elf64-ppc.c (ppc_build_one_stub): Don't check save_res offsets.
Let's show the current stub as well as the previous one. Of interest
is the current offset and a new field, id. Check that the build
hash table traversal is in the same order as sizing traversal too.
* elf64-ppc.c (struct ppc_stub_hash_entry): Add id.
(struct ppc_link_hash_table): Add stub_id.
(stub_hash_newfunc): Init id and symtype.
(dump_stub): New function, extracted from..
(dump_previous_stub): ..here. Deleted.
(ppc_build_one_stub): Sanity check stub id as well as offset.
Show current stub as well as previous.
(ppc_size_one_stub): Set stub id.
(ppc64_elf_size_stubs): Init stub_id before traversal.
(ppc64_elf_build_stubs): Likewise.
__attribute__((visibility("protected"))) void *foo() {
return (void *)foo;
}
gcc -fpic -shared -fuse-ld=bfd fails with the confusing diagnostic:
relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `foo' which may bind externally can not be used when making a shared object; recompile with -fPIC
Call _bfd_elf_symbol_refs_local_p with local_protected==true to suppress
the error. The new behavior matches gold and ld.lld.
Note: if some code tries to use direct access relocations to take the
address of foo (likely due to -fno-pic), the pointer equality will
break, but the error should be reported on the executable link, not on
the innocent shared object link. glibc 2.36 will give a warning at
relocation resolving time.
Follow-up to commit 90b7a5df15
("aarch64: Disallow copy relocations on protected data").
Commit 32f573bcb3 changed ld to produce
R_AARCH64_GLOB_DAT but that defeated the purpose of protected visibility
as an optimization. Restore the previous behavior (which matches
ld.lld) by defining elf_backend_extern_protected_data to 0.
If an executable has copy relocations for extern protected data, that
can only work if the shared object containing the definition is built
with assumptions (a) the compiler emits GOT-generating relocations (b)
the linker produces R_*_GLOB_DAT instead of R_*_RELATIVE. Otherwise the
shared object uses its own definition directly and the executable
accesses a stale copy. Note: the GOT relocations defeat the purpose of
protected visibility as an optimization, and it turns out this never
worked perfectly.
glibc 2.36 will warn on copy relocations on protected data. Let's
produce a warning at link time, matching ld.lld which has been used on
many aarch64 OSes.
Note: x86 requires GNU_PROPERTY_NO_COPY_ON_PROTECTED to have the error.
This is to largely due to GCC 5's "x86-64: Optimize access to globals in
PIE with copy reloc" which started to use direct access relocations for
external data symbols in -fpie mode.
GCC's aarch64 port does not have the change. Nowadays with most builds
switching to -fpie/-fpic, aarch64 mostly doesn't need to worry about
copy relocations. So for aarch64 we simply don't check
GNU_PROPERTY_NO_COPY_ON_PROTECTED.
This patch has been pending for almost a year... However, I noticed that
llvm can already re-order the extensions, even if they are out of orders.
Not really sure if they can also re-order the single letter extensions,
but at least we can do this for the multi-letter extensions in binutils.
bfd/
* elfxx-riscv.c (riscv_parse_prefixed_ext): Removed the code which are
used to check the prefixed extension orders.
gas/
* testsuite/gas/riscv/march-fail-order-x-z.d: Removed since we will help
tp reorder the prefixed extensions for now.
* testsuite/gas/riscv/march-fail-order-x-z.l: Likewise.
* testsuite/gas/riscv/march-fail-order-x.d: Likewise.
* testsuite/gas/riscv/march-fail-order-x.l: Likewise.
* testsuite/gas/riscv/march-fail-order-z.d: Likewise.
* testsuite/gas/riscv/march-fail-order-z.l: Likewise.
According to the picture 28.1 in the current ISA spec, h is no larger the
multi-letter extension, it is a single extension after v. Therefore, this
patch fix the implementation, and use the single h to control hypervisor
CSRs and instructions, which we promised to do before.
bfd/
* elfxx-riscv.c (riscv_supported_std_ext): Added h with version 1.0 after v.
(riscv_supported_std_h_ext): Removed.
(riscv_all_supported_ext): Updated since riscv_supported_std_h_ext is removed.
(riscv_prefix_ext_class): Removed RV_ISA_CLASS_H.
(parse_config): Updated since riscv_prefix_ext_class is removed.
(riscv_recognized_prefixed_ext): Likewise.
(riscv_get_default_ext_version): Likewise.
(riscv_multi_subset_supports): Handle INSN_CLASS_H for hypervisor instructions.
(riscv_multi_subset_supports_ext): Likewise.
gas/
* config/tc-riscv.c (riscv_csr_class): Added CSR_CLASS_H and CSR_CLASS_H_32 for
hypervisor CSRs.
(riscv_csr_address): Likewise.
* testsuite/gas/riscv/csr-version-1p10.d: Updated since hypervisor CSRs are
controlled by single h extension for now.
* testsuite/gas/riscv/csr-version-1p10.l: Likewise.
* testsuite/gas/riscv/csr-version-1p11.d: Likewise.
* testsuite/gas/riscv/csr-version-1p11.l: Likewise.
* testsuite/gas/riscv/csr-version-1p12.d: Likewise.
* testsuite/gas/riscv/csr-version-1p12.l: Likewise.
* testsuite/gas/riscv/csr-version-1p9p1.d: Likewise.
* testsuite/gas/riscv/csr-version-1p9p1.l: Likewise.
* testsuite/gas/riscv/h-ext-32.d: Added h to architecture string.
* testsuite/gas/riscv/h-ext-64.d: Likewise.
* testsuite/gas/riscv/march-fail-single-prefix-h: Removed since h is no
longer multi-letter extension.
* testsuite/gas/riscv/march-fail-unknown-h.d: Likewise.
include/
* opcode/riscv-opc.h: Control hypervisor CSRs by h extension, rather than
the privileged spec verisons.
* opcode/riscv.h (riscv_insn_class): Added INSN_CLASS_H.
opcodes/
* riscv-opc.c (riscv_opcodes): Control hypervisor instructions by h extension.
This commit adds 'H' to canonical extension ordering based on current
consensus (not officially ratified as a new ISA specification manual
but discussion for software compatibility is made).
bfd/ChangeLog
* elfxx-riscv.c (riscv_ext_canonical_order): Add 'H' for
canonical extension ordering based on current consensus.
Some strings returned by the riscv_multi_subset_supports_ext function
contain not just extension names but words like "and" and "or".
This commit wraps such strings with the gettext macro (_) for
internationalization in the future.
bfd/ChangeLog:
* elfxx-riscv.c (riscv_multi_subset_supports_ext): Wrap some
strings with the gettext macro to prepare future i18n.
powerpc64le-linux-ld is failing the assertion in ppc_build_one_stub,
again apparently, which means a stub will overwrite the tail of a
previous stub. The difficulty with debugging these issues is that
it's not a problem with the stub that triggers the assertion, but the
previous stub in that section. This patch keeps track of the last
stub and adds a debug dump. Hopefully that will help.
* elf64-ppc.c (enum _ppc64_sec_type): Add sec_stub.
(struct _ppc64_elf_section_data): Add u.last_ent.
(dump_previous_stub): New function.
(ppc_build_one_stub): Keep track of previous stub, and dump it
when finding an overlapping stub.
The optimized insertion sort algorithm in `elf_link_adjust_relocs`
incorrectly assembled "runs" from unsorted entries and inserted them to an
already-sorted prefix, breaking the loop invariants of insertion sort.
This commit updates the run assembly loop to break upon encountering a
non-monotonic change in the sort key.
PR 29259
bfd/
* elflink.c (elf_link_adjust_relocs): Ensure run being inserted
is sorted.
ld/
* testsuite/ld-elf/pr29259.d,
* testsuite/ld-elf/pr29259.s,
* testsuite/ld-elf/pr29259.t: New test.
The PR23230 testcase uses indexed strings without specifying
SW_AT_str_offsets_base. In this case we left u.str with garbage (from
u.val) which then led to a segfault when attempting to access the
string. Fix that by clearing u.str. The patch also adds missing
sanity checks in the recently committed read_indexed_address and
read_indexed_string functions.
PR 29230
* dwarf2.c (read_indexed_address): Return uint64_t. Sanity check idx.
(read_indexed_string): Use uint64_t for str_offset. Sanity check idx.
(read_attribute_value): Clear u.str for indexed string forms when
DW_AT_str_offsets_base is not yet read or missing.
On Thu, Jun 09, 2022 at 08:59:37AM -0700, John Baldwin wrote:
> On 6/9/22 1:58 AM, Tom de Vries via Gdb-patches wrote:
> > Hi,
> >
> > With an --enable-targets=all build and target board unix/-m32 I run into a
> > FAIL in test-case gdb.base/corefile.exp:
> > ...
> > (gdb) file outputs/gdb.base/corefile/corefile^M
> > Reading symbols from outputs/gdb.base/corefile/corefile...^M
> > (gdb) core-file outputs/gdb.base/corefile/corefile.core^M
> > warning: core file may not match specified executable file.^M
> > [New LWP 12011]^M
> > Core was generated by `outputs/gdb.base/corefile/co'.^M
> > Program terminated with signal SIGABRT, Aborted.^M
> > (gdb) FAIL: gdb.base/corefile.exp: core-file warning-free
> > ...
> >
> > The warning is there because of this mismatch between core and exec:
> > ...
> > (gdb) p core_bfd->xvec
> > $3 = (const struct bfd_target *) 0x20112a0 <i386_elf32_fbsd_vec>
> > (gdb) p exec_bfd->xvec
> > $4 = (const struct bfd_target *) 0x2010b00 <i386_elf32_vec>
> > ...
> >
> > In the exec case, the detected architecture is i386_elf32_vec because this bit
> > of code in elfcode.h:elf_object_p():
> > ...
> > if (ebd->elf_machine_code != EM_NONE
> > && i_ehdrp->e_ident[EI_OSABI] != ebd->elf_osabi
> > && ebd->elf_osabi != ELFOSABI_NONE)
> > goto got_wrong_format_error;
> > ...
> > prevents i386_elf32_fbsd from matching.
> >
> > Fix the core matching by copying that code to elfcore.h:elf_core_file_p().
> >
> > Tested on x86_64-linux.
> >
> > Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29227
> >
> > Any comments?
Looks good.
> Looking at elfcore.h, it seems to have not gotten changes made to elfcode.h over
> time and is a bit rotted. I suspect that all of changes made in commit 0aabe54e62
> that added these lines in elfcode.h (along with several other changes) need to
> be applied to this function in elfcore.h, not just adding these lines.
Yes, the commit 0aabe54e62 changes likely should go in too. I'm a
little wary of adding all the sanity checks to elf_core_file_p since
that might result in some core files not being recognised at all. For
example, despite the FIXME I'd guess leaving out the EI_VERSION check
was deliberate. The following seems reasonable to me. Please test.
MIPS should not be using BFD_RELOC_16 for its R_MIPS_16 relocation,
since R_MIPS_16 specifies a 16-bit field in a 32-bit word.
BFD_RELOC_16, emitted by generic code to handle fixups on 16-bit data
directives, expects fixups to operate on the whole of a 16-bit word.
This patch corrects the problem by using BFD_RELOC_MIPS_16, a new bfd
reloc that is used to generate R_MIPS_16. BFD_RELOC_16 is handled in
md_apply_fix for cases where the fixup can be applied at assembly
time. Like BFD_RELOC_8, BFD_RELOC_16 now has no corresponding object
file relocation, and thus .half, .hword, .short and .dc.w must be
resolved at assembly time. BFD_RELOC_MIPS_REL16 is removed by this
patch since it isn't used.
PR 3243
PR 26542
* reloc.c (BFD_RELOC_MIPS_16): Rename from BFD_RELOC_MIPS_REL16.
* elf32-mips.c (mips_reloc_map): Map BFD_RELOC_MIPS_16 to R_MIPS_16.
* elf64-mips.c (mips_reloc_map): Likewise, delete BFD_RELOC_MIPS_REL16.
* elfn32-mips.c (mips_reloc_map): Likewise.
* libbfd.h: Regenerate.
* bfd-in2.h: Regenerate.
gas/
* config/tc-mips.c (append_insn): Handle BFD_RELOC_MIPS_16.
(macro_build): Likewise.
(mips_percent_op <%half>): Generate BFD_RELOC_MIPS_16.
(md_apply_fix): Handle BFD_RELOC_16 and BFD_RELOC_MIPS_16 when fx_done.
ld/
* testsuite/ld-mips-elf/reloc-local-overflow.d,
* testsuite/ld-mips-elf/reloc-local-overflow.s: Rewrite.
If the howto is actually used, an all-zero dst_mask will result in
unchanged section contents on attempting to apply R_MIPS_16.
* elfn32-mips.c (elf_mips_howto_table_rela <R_MIPS_16>): Correct
dst_mask.
I expect the encoded reloc.size field originally came from aout
r_length ecoding, but somehow went wrong for 64-bit relocs (which
should have been encoded as 3). Toss all that out, just use a byte
size instead. The changes outside of reloc.c in this patch should
make the code independent of how reloc.size is encoded.
* reloc.c (struct reloc_howto_struct): Increase size field by
one bit. Comment.
(HOWTO_RSIZE): Don't encode size.
(bfd_get_reloc_size): Adjust, and make it an inline function.
(read_reloc, write_reloc): Adjust.
* bfd-in2.h: Regenerate.
* aout-ns32k.c: Include libbfd.h.
(put_reloc): Don't use howto->size directly. Calculate r_length
using bfd_log2 and bfd_get_reloc_size.
* aoutx.h (swap_std_reloc_out): Likewise.
(aout_link_reloc_link_order): Likewise.
* i386lynx.c (swap_std_reloc_out
* mach-o-i386.c (bfd_mach_o_i386_swap_reloc_out
* pdp11.c (aout_link_reloc_link_order
* coff-arm.c (coff_arm_reloc): Don't use howto->size directly,
use bfd_get_reloc_size instead and adjust switch cases.
* coff-i386.c (coff_i386_reloc): Similarly.
* coff-x86_64.c (coff_amd64_reloc): Likewise.
* cpu-ns32k.c (do_ns32k_reloc): Likewise.
* elf32-arc.c (arc_do_relocation): Likewise.
* elf32-arm.c (elf32_arm_final_link_relocate): Likewise.
* elf32-bfin.c (bfin_bfd_reloc): Likewise.
* elf32-cr16.c (cr16_elf_final_link_relocate): Likewise.
* elf32-cris.c (cris_elf_pcrel_reloc): Likewise.
* elf32-crx.c (crx_elf_final_link_relocate): Likewise.
* elf32-csky.c (csky_elf_relocate_section): Likewise.
* elf32-d10v.c (extract_rel_addend, insert_rel_addend): Likewise.
* elf32-i386.c (elf_i386_relocate_section): Likewise.
* elf32-m32r.c (m32r_elf_generic_reloc): Likewise.
* elf32-nds32.c (nds32_elf_generic_reloc): Likewise.
* syms.c (_bfd_stab_section_find_nearest_line): Likewise.
* coff-rs6000.c (xcoff_ppc_relocate_section): Adjust howto.size.
* coff64-rs6000.c (xcoff64_ppc_relocate_section): Likewise.
These all ought to use bfd_reloc_offset_in_range. In particular, replace
the check using howto->size + 1u.
* elf32-bfin.c (bfin_pcrel24_reloc): Use bfd_reloc_offset_in_range.
(bfin_imm16_reloc, bfin_byte4_reloc, bfin_bfd_reloc),
(bfin_final_link_relocate): Likewise.
The "HOWTO size encoding" patch put 1 as the HOWTO size arg for
numerous howtos that are unused, describe dynamic relocs, are markers,
or otherwise are special purpose reloc howtos that don't care about
the size. The idea was to ensure no howto changed by inspecting
object files. Revert those changes, making them zero size.
* coff-alpha.c: Give special purpose reloc howtos a size of zero.
* coff-mcore.c, * elf-hppa.h, * elf-m10300.c, * elf32-arm.c,
* elf32-csky.c, * elf32-m32c.c, * elf32-m68k.c, * elf32-mep.c,
* elf32-mips.c, * elf32-ppc.c, * elf32-rx.c, * elf32-s390.c,
* elf32-spu.c, * elf32-tic6x.c, * elf32-tilepro.c, *elf32-vax.c,
* elf32-xtensa.c, * elf64-alpha.c, * elf64-mips.c,
* elf64-mmix.c, * elf64-ppc.c, * elf64-s390.c, * elfn32-mips.c,
* elfxx-loongarch.c, * elfxx-riscv.c, * elfxx-sparc.c,
* elfxx-tilegx.c, * som.c, * vms-alpha.c: Likewise.
These are all dummy howtos, there is no reason one of them should
have partial_inplace true.
* elf64-nfp.c (elf_nfp_howto_table <R_NFP_IMMED_LO16_I_B>): Don't
set partial_inplace.
Mostly cosmetic unless attempting to link coff-z80 into another output
format.
* coff-z80.c (howto_table <R_IMM24, R_WORD0, R_WORD1>): Correct size.
(extra_case): Use bfd_{get,put}_24 when applying R_IMM24.