x86: widen @got{,pcrel} support to PUSH and APX IMUL
With us doing the transformation to an immediate operand for MOV and
various ALU insns, there's little reason to then not support the same
conversion for the other two insns which have respective immediate
operand forms. Unfortunately for IMUL (due to the 0F opcode prefix)
there's no suitable relocation, so the pre-APX forms cannot be marked
for relaxation in the assembler.
"pushl main@GOT(%ebx)" in sysdeps/i386/start.S was assembled to
Linkers in binutils versions older than 2.45 treated it as jmp and relaxed
it to
22c: e9 cf ff ff ff jmp 200 <main>
231: 90 nop
Update elf_i386_convert_load_reloc in binutils versions older than 2.45
to check MODRM for call and jmp to work with i386 glibc assembled with
binutils 2.45 or newer. Do the same in elf_x86_64_convert_load_reloc.
PR ld/32991
* elf32-i386.c (elf_i386_convert_load_reloc): Check MODRM for
call and jmp.
* elf64-x86-64.c (elf_x86_64_convert_load_reloc): Likewise.
Nick Alcock [Mon, 29 Jul 2024 11:45:09 +0000 (12:45 +0100)]
libctf: fix ref leak of names of newly-inserted non-root-visible types
A bug in ctf_dtd_delete led to refs in the string table to the
names of non-root-visible types not being removed when the DTD
was. This seems harmless, but actually it would lead to a write
down a pointer into freed memory if such a type was ctf_rollback()ed
over and then the dict was serialized (updating all the refs as the
strtab was serialized in turn).
Bug introduced in commit fe4c2d55634c700ba527ac4183e05c66e9f93c62
("libctf: create: non-root-visible types should not appear in name tables")
which is included in binutils 2.35.
libctf/
* ctf-create.c (ctf_dtd_delete): Remove refs for all types
with names, not just root-visible ones.
Alan Modra [Fri, 4 Aug 2023 05:39:53 +0000 (15:09 +0930)]
PR30697, ppc32 mix of local-dynamic and global-dynamic TLS
This fixes miscounting of dynamic relocations on GOT entries when
a) there are both local-dynamic and global-dynamic tls accesss for a
given symbol, and
b) the symbol is global with non-default visibility, and
c) the __tls_get_addr calls aren't optimised away.
PR 30697
bfd/
* elf32-ppc.c (allocate_dynrelocs): Correct local-dynamic
reloc count.
ld/
* testsuite/ld-powerpc/tls32ldgd.d,
* testsuite/ld-powerpc/tls32ldgd.s: New test.
* testsuite/ld-powerpc/powerpc.exp: Run it.
Alan Modra [Tue, 20 Sep 2022 23:36:29 +0000 (09:06 +0930)]
Re: PowerPC64 pcrel got relocs against local symbols
The last patch wasn't all that shiny. There are rather a lot more
relocations that can hit the assertion in md_apply_fix if the symbol
is local or absolute. Fix them all.
* config/tc-ppc.c (ppc_force_relocation): Add all relocs that
expect a symbol in md_apply_fix. Remove tls pcrel relocs
already covered in general tls match range.
Alan Modra [Fri, 16 Sep 2022 08:38:44 +0000 (18:08 +0930)]
PowerPC64 pcrel got relocs against local symbols
Not that anyone would want to indirect via the GOT when an address can
be loaded directly with pla, the following:
pld 3,x@got@pcrel
x:
leads to "Internal error in md_apply_fix", because the generic parts
of assembler fixup handling convert the fx_pcrel fixup to one without
a symbol. Stop that happening.
* config/tc-ppc.c (ppc_force_relocation): Add PLT_PCREL34 and
assorted GOT_PCREL34 relocs.
H.J. Lu [Mon, 18 Jul 2022 18:44:32 +0000 (11:44 -0700)]
x86: Properly check invalid relocation against protected symbol
Only check invalid relocation against protected symbol defined in shared
object.
bfd/
PR ld/29377
* elf32-i386.c (elf_i386_scan_relocs): Only check invalid
relocation against protected symbol defined in shared object.
* elf64-x86-64.c (elf_x86_64_scan_relocs): Likewise.
ld/
PR ld/29377
* testsuite/ld-elf/linux-x86.exp: Run PR ld/29377 tests.
* testsuite/ld-elf/pr29377a.c: New file.
* testsuite/ld-elf/pr29377b.c: Likewise.
Nick Alcock [Sat, 11 Jun 2022 12:07:18 +0000 (13:07 +0100)]
libctf: tests: prune warnings from compiler output
We were failing to call prune_warnings appropriately, leading to
false-positive test failures on some platforms (observed on
sparclinux).
libctf/ChangeLog:
* testsuite/lib/ctf-lib.exp: Prune warnings from compiler and
linker output.
* testsuite/libctf-regression/libctf-repeat-cu.exp: Likewise,
and ar output too.
Nick Alcock [Fri, 10 Jun 2022 16:05:50 +0000 (17:05 +0100)]
libctf: fix linking together multiple objects derived from the same source
Right now, if you compile the same .c input repeatedly with CTF enabled
and different compilation flags, then arrange to link all of these
together, then things misbehave in various ways. libctf may conflate
either inputs (if the .o files have the same name, say if they are
stored in different .a archives), or per-CU outputs when conflicting
types are found: the latter can lead to entirely spurious errors when
it tries to produce multiple per-CU outputs with the same name
(discarding all but the last, but then looking for types in the earlier
ones which have just been thrown away).
Fixing this is multi-pronged. Both inputs and outputs need to be
differentiated in the hashtables libctf keeps them in: inputs with the
same cuname and filename need to be considered distinct as long as they
have different associated CTF dicts, and per-CU outputs need to be
considered distinct as long as they have different associated input
dicts. Right now there is nothing tying the two together other than the
CU name: fix this by introducing a new field in the ctf_dict_t named
ctf_link_in_out, which (for input dicts) points to the associated per-CU
output dict (if any), and for output dicts points to the associated
input dict. At creation time the name used is completely arbitrary:
it's only important that it be distinct if CTF dicts are distinct. So,
when a clash is found, adjust the CU name by sticking the number of
elements in the input on the end. At output time, the CU name will
appear in the linked object, so it matters a little more that it look
slightly less ugly: in conflicting cases, append an incrementing
integer, starting at 0.
This naming scheme is not very helpful, but it's hard to see what else
we can do. The input .o name may be the same. The input .a name is not
even visible to ctf_link, and even *that* might be the same, because
.a's can contain many members with the same name, all of which
participate in the link. All we really know is that the two have
distinct dictionaries with distinct types in them, and at least this way
they are all represented, any any symbols, variables etc referring to
those types are accurately stored.
(As a side-effect this also fixes a use-after-free and double-free when
errors are found during variable or symbol emission.)
Use the opportunity to prevent a couple of sources of problems, to wit
changing the active CU mappings when a link has already been done
(no effect on ld, which doesn't use CU mappings at all), and causing
multiple consecutive ctf_link's to have the same net effect as just
doing the last one (no effect on ld, which only ever does one
ctf_link) rather than having the links be a sort of half-incremental
not-really-intended mess.
libctf/ChangeLog:
PR libctf/29242
* ctf-impl.h (struct ctf_dict) [ctf_link_in_out]: New.
* ctf-dedup.c (ctf_dedup_emit_type): Set it.
* ctf-link.c (ctf_link_add_ctf_internal): Set the input
CU name uniquely when clashes are found.
(ctf_link_add): Document what repeated additions do.
(ctf_new_per_cu_name): New, come up with a consistent
name for a new per-CU dict.
(ctf_link_deduplicating): Use it.
(ctf_create_per_cu): Use it, and ctf_link_in_out, and set
ctf_link_in_out properly. Don't overwrite per-CU dicts with
per-CU dicts relating to different inputs.
(ctf_link_add_cu_mapping): Prevent per-CU mappings being set up
if we already have per-CU outputs.
(ctf_link_one_variable): Adjust ctf_link_per_cu call.
(ctf_link_deduplicating_one_symtypetab): Likewise.
(ctf_link_empty_outputs): New, delete all the ctf_link_outputs
and blank out ctf_link_in_out on the corresponding inputs.
(ctf_link): Clarify the effect of multiple ctf_link calls.
Empty ctf_link_outputs if it already exists rather than
having the old output leak into the new link. Fix a variable
name.
* testsuite/config/default.exp (AR): Add.
(OBJDUMP): Likewise.
* testsuite/libctf-regression/libctf-repeat-cu.exp: New test.
* testsuite/libctf-regression/libctf-repeat-cu*: Main program,
library, and expected results for the test.
to properly handle IFUNC function pointer reference. Since IFUNC symbol
value is only known at run-time, set pointer_equality_needed for IFUNC
function pointer reference in PDE so that it will be resolved to its PLT
entry directly.
bfd/
PR ld/29216
* elf32-i386.c (elf_i386_scan_relocs): Set pointer_equality_needed
for IFUNC function pointer reference in PDE.
* elf64-x86-64.c (elf_x86_64_scan_relocs): Likewise.
ld/
PR ld/29216
* testsuite/ld-ifunc/ifunc.exp: Run PR ld/29216 test.
* testsuite/ld-ifunc/pr29216.c: New file.
Tamar Christina [Wed, 18 May 2022 09:37:10 +0000 (10:37 +0100)]
AArch64: Enable FP16 by default for Armv9-A.
In Armv9-A SVE is mandatory, and for SVE FP16 is mandatory. This fixes a disconnect
between GCC and binutils where GCC has FP16 on by default and gas doesn't.
include/ChangeLog:
2022-05-16 Tamar Christina <tamar.christina@arm.com>
M68K: avoid quadratic slowdlow in label alignment check
Before the change tc-m68k maintained a list of seen labels.
Alignment check traversed label list to resolve symbol to label.
This caused quadratic slowdown as each symbol was checked against
each label. Worst affected files are the ones built with debugging
enabled as DWARF generates many labels.
The change embeds auxiliary label information right into symbol using
TC_SYMFIELD_TYPE.
Before the change test from PR 29058 did not finish in 10 minutes. After
the change it finishes in 2 seconds.
gas/ChangeLog:
PR 29058
* config/tc-m68k.h (TC_SYMFIELD_TYPE): define as m68k_tc_sy.
* config/tc-m68k.c (m68k_frob_label): Use TC_SYMFIELD_TYPE to
store label information.
x86: Disallow invalid relocation against protected symbol
to allow function pointer reference and make sure that PLT entry isn't
used for function reference due to function pointer reference.
bfd/
PR ld/29087
* elf32-i386.c (elf_i386_scan_relocs): Don't set
pointer_equality_needed nor check non-canonical reference for
function pointer reference.
* elf64-x86-64.c (elf_x86_64_scan_relocs): Likewise.
ld/
PR ld/29087
* testsuite/ld-x86-64/x86-64.exp: Run PR ld/29087 tests.
* testsuite/ld-x86-64/protected-func-3.c: New file.
Stefan Liebler [Thu, 28 Apr 2022 12:30:55 +0000 (14:30 +0200)]
s390: Add DT_JMPREL pointing to .rela.[i]plt with static-pie
In static-pie case, there are IRELATIVE-relocs in
.rela.iplt (htab->irelplt), which will later be grouped
to .rela.plt. On s390, the IRELATIVE relocations are
always located in .rela.iplt - even for non-static case.
Ensure that DT_JMPREL, DT_PLTRELA, DT_PLTRELASZ is added
to the dynamic section even if htab->srelplt->size == 0.
See _bfd_elf_add_dynamic_tags in bfd/elflink.c.
bfd/
elf64-s390.c (elf_s390_size_dynamic_sections):
Enforce DT_JMPREL via htab->elf.dt_jmprel_required.