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[PATCH] x86-64: Move PIC check for PC-relative relocations back
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: Binutils <binutils at sourceware dot org>
- Date: Thu, 15 Aug 2019 15:02:34 -0700
- Subject: [PATCH] x86-64: Move PIC check for PC-relative relocations back
commit 83924b3846361f2f76f9a6e7b5afa01c0eebbd4f
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Tue Feb 5 18:45:23 2019 -0800
x86-64: Restore PIC check for PCREL reloc against protected symbol
moved PIC check for PC-relative relocations to elf_x86_64_check_relocs.
Since linker defined symbols may not be processed at the time, we need
to move the back to elf_x86_64_relocate_section.
bfd/
PR ld/24905
* elf64-x86-64.c (elf_x86_64_check_relocs): Move PIC check for
PC-relative relocations back to ...
(elf_x86_64_relocate_section): Here.
ld/testsuite/
PR ld/24905
* ld-x86-64/pr24905-x32.d: New file.
* ld-x86-64/pr24905.d: Likewise.
* ld-x86-64/pr24905.s: Likewise.
* ld-x86-64/pr24905.t: Likewise.
* testsuite/ld-x86-64/x86-64.exp: Run pr24905 and pr24905-x32.
--
H.J.
From ba2907f2058d207d1adba4c3753bfda8a9502c33 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 15 Aug 2019 14:56:00 -0700
Subject: [PATCH] x86-64: Move PIC check for PC-relative relocations back
commit 83924b3846361f2f76f9a6e7b5afa01c0eebbd4f
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Tue Feb 5 18:45:23 2019 -0800
x86-64: Restore PIC check for PCREL reloc against protected symbol
moved PIC check for PC-relative relocations to elf_x86_64_check_relocs.
Since linker defined symbols may not be processed at the time, we need
to move the back to elf_x86_64_relocate_section.
bfd/
PR ld/24905
* elf64-x86-64.c (elf_x86_64_check_relocs): Move PIC check for
PC-relative relocations back to ...
(elf_x86_64_relocate_section): Here.
ld/testsuite/
PR ld/24905
* ld-x86-64/pr24905-x32.d: New file.
* ld-x86-64/pr24905.d: Likewise.
* ld-x86-64/pr24905.s: Likewise.
* ld-x86-64/pr24905.t: Likewise.
* testsuite/ld-x86-64/x86-64.exp: Run pr24905 and pr24905-x32.
---
bfd/elf64-x86-64.c | 149 +++++++++++++--------------
ld/testsuite/ld-x86-64/pr24905-x32.d | 8 ++
ld/testsuite/ld-x86-64/pr24905.d | 7 ++
ld/testsuite/ld-x86-64/pr24905.s | 6 ++
ld/testsuite/ld-x86-64/pr24905.t | 1 +
ld/testsuite/ld-x86-64/x86-64.exp | 2 +
6 files changed, 94 insertions(+), 79 deletions(-)
create mode 100644 ld/testsuite/ld-x86-64/pr24905-x32.d
create mode 100644 ld/testsuite/ld-x86-64/pr24905.d
create mode 100644 ld/testsuite/ld-x86-64/pr24905.s
create mode 100644 ld/testsuite/ld-x86-64/pr24905.t
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 34180c7552..e5c8003a68 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -1864,7 +1864,6 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
const char *name;
bfd_boolean size_reloc;
bfd_boolean converted_reloc;
- bfd_boolean do_check_pic;
r_symndx = htab->r_sym (rel->r_info);
r_type = ELF32_R_TYPE (rel->r_info);
@@ -2136,13 +2135,6 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
size_reloc = TRUE;
goto do_size;
- case R_X86_64_PC8:
- case R_X86_64_PC16:
- case R_X86_64_PC32:
- case R_X86_64_PC32_BND:
- do_check_pic = TRUE;
- goto check_pic;
-
case R_X86_64_32:
if (!ABI_64_P (abfd))
goto pointer;
@@ -2166,11 +2158,13 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
&x86_64_elf_howto_table[r_type]);
/* Fall through. */
+ case R_X86_64_PC8:
+ case R_X86_64_PC16:
+ case R_X86_64_PC32:
+ case R_X86_64_PC32_BND:
case R_X86_64_PC64:
case R_X86_64_64:
pointer:
- do_check_pic = FALSE;
-check_pic:
if (eh != NULL && (sec->flags & SEC_CODE) != 0)
eh->zero_undefweak |= 0x2;
/* We are called after all symbols have been resolved. Only
@@ -2234,69 +2228,6 @@ check_pic:
}
}
- if (do_check_pic)
- {
- /* Don't complain about -fPIC if the symbol is undefined
- when building executable unless it is unresolved weak
- symbol, references a dynamic definition in PIE or
- -z nocopyreloc is used. */
- bfd_boolean no_copyreloc_p
- = (info->nocopyreloc
- || (h != NULL
- && !h->root.linker_def
- && !h->root.ldscript_def
- && eh->def_protected
- && elf_has_no_copy_on_protected (h->root.u.def.section->owner)));
- if ((sec->flags & SEC_ALLOC) != 0
- && (sec->flags & SEC_READONLY) != 0
- && h != NULL
- && ((bfd_link_executable (info)
- && ((h->root.type == bfd_link_hash_undefweak
- && (eh == NULL
- || !UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
- eh)))
- || (bfd_link_pie (info)
- && !SYMBOL_DEFINED_NON_SHARED_P (h)
- && h->def_dynamic)
- || (no_copyreloc_p
- && h->def_dynamic
- && !(h->root.u.def.section->flags & SEC_CODE))))
- || bfd_link_dll (info)))
- {
- bfd_boolean fail = FALSE;
- if (SYMBOL_REFERENCES_LOCAL_P (info, h))
- {
- /* Symbol is referenced locally. Make sure it is
- defined locally. */
- fail = !SYMBOL_DEFINED_NON_SHARED_P (h);
- }
- else if (bfd_link_pie (info))
- {
- /* We can only use PC-relative relocations in PIE
- from non-code sections. */
- if (h->type == STT_FUNC
- && (sec->flags & SEC_CODE) != 0)
- fail = TRUE;
- }
- else if (no_copyreloc_p || bfd_link_dll (info))
- {
- /* Symbol doesn't need copy reloc and isn't
- referenced locally. Don't allow PC-relative
- relocations against default and protected
- symbols since address of protected function
- and location of protected data may not be in
- the shared object. */
- fail = (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
- || ELF_ST_VISIBILITY (h->other) == STV_PROTECTED);
- }
-
- if (fail)
- return elf_x86_64_need_pic (info, abfd, sec, h,
- symtab_hdr, isym,
- &x86_64_elf_howto_table[r_type]);
- }
- }
-
size_reloc = FALSE;
do_size:
if (NEED_DYNAMIC_RELOCATION_P (info, TRUE, h, sec, r_type,
@@ -2497,6 +2428,7 @@ elf_x86_64_relocate_section (bfd *output_bfd,
bfd_boolean relative_reloc;
bfd_boolean converted_reloc;
bfd_boolean need_copy_reloc_in_pie;
+ bfd_boolean no_copyreloc_p;
r_type = ELF32_R_TYPE (rel->r_info);
if (r_type == (int) R_X86_64_GNU_VTINHERIT
@@ -3137,14 +3069,73 @@ use_plt:
case R_X86_64_PC16:
case R_X86_64_PC32:
case R_X86_64_PC32_BND:
+ /* Don't complain about -fPIC if the symbol is undefined when
+ building executable unless it is unresolved weak symbol,
+ references a dynamic definition in PIE or -z nocopyreloc
+ is used. */
+ no_copyreloc_p
+ = (info->nocopyreloc
+ || (h != NULL
+ && !h->root.linker_def
+ && !h->root.ldscript_def
+ && eh->def_protected
+ && elf_has_no_copy_on_protected (h->root.u.def.section->owner)));
+
+ if ((input_section->flags & SEC_ALLOC) != 0
+ && (input_section->flags & SEC_READONLY) != 0
+ && h != NULL
+ && ((bfd_link_executable (info)
+ && ((h->root.type == bfd_link_hash_undefweak
+ && (eh == NULL
+ || !UNDEFINED_WEAK_RESOLVED_TO_ZERO (info,
+ eh)))
+ || (bfd_link_pie (info)
+ && !SYMBOL_DEFINED_NON_SHARED_P (h)
+ && h->def_dynamic)
+ || (no_copyreloc_p
+ && h->def_dynamic
+ && !(h->root.u.def.section->flags & SEC_CODE))))
+ || bfd_link_dll (info)))
+ {
+ bfd_boolean fail = FALSE;
+ if (SYMBOL_REFERENCES_LOCAL_P (info, h))
+ {
+ /* Symbol is referenced locally. Make sure it is
+ defined locally. */
+ fail = !SYMBOL_DEFINED_NON_SHARED_P (h);
+ }
+ else if (bfd_link_pie (info))
+ {
+ /* We can only use PC-relative relocations in PIE
+ from non-code sections. */
+ if (h->type == STT_FUNC
+ && (sec->flags & SEC_CODE) != 0)
+ fail = TRUE;
+ }
+ else if (no_copyreloc_p || bfd_link_dll (info))
+ {
+ /* Symbol doesn't need copy reloc and isn't
+ referenced locally. Don't allow PC-relative
+ relocations against default and protected
+ symbols since address of protected function
+ and location of protected data may not be in
+ the shared object. */
+ fail = (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
+ || ELF_ST_VISIBILITY (h->other) == STV_PROTECTED);
+ }
+
+ if (fail)
+ return elf_x86_64_need_pic (info, input_bfd, input_section,
+ h, NULL, NULL, howto);
+ }
/* Since x86-64 has PC-relative PLT, we can use PLT in PIE
as function address. */
- if (h != NULL
- && (input_section->flags & SEC_CODE) == 0
- && bfd_link_pie (info)
- && h->type == STT_FUNC
- && !h->def_regular
- && h->def_dynamic)
+ else if (h != NULL
+ && (input_section->flags & SEC_CODE) == 0
+ && bfd_link_pie (info)
+ && h->type == STT_FUNC
+ && !h->def_regular
+ && h->def_dynamic)
goto use_plt;
/* Fall through. */
diff --git a/ld/testsuite/ld-x86-64/pr24905-x32.d b/ld/testsuite/ld-x86-64/pr24905-x32.d
new file mode 100644
index 0000000000..e2c6a73076
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr24905-x32.d
@@ -0,0 +1,8 @@
+#source: pr24905.s
+#as: --x32
+#ld: -shared -melf32_x86_64 $srcdir/$subdir/pr24905.t
+#nm: -n
+
+#...
+[0-9a-f]* t EXTERNAL_SYM
+#pass
diff --git a/ld/testsuite/ld-x86-64/pr24905.d b/ld/testsuite/ld-x86-64/pr24905.d
new file mode 100644
index 0000000000..f11834f12b
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr24905.d
@@ -0,0 +1,7 @@
+#as: --64
+#ld: -shared -melf_x86_64 $srcdir/$subdir/pr24905.t
+#nm: -n
+
+#...
+[0-9a-f]* t EXTERNAL_SYM
+#pass
diff --git a/ld/testsuite/ld-x86-64/pr24905.s b/ld/testsuite/ld-x86-64/pr24905.s
new file mode 100644
index 0000000000..73a5d58032
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr24905.s
@@ -0,0 +1,6 @@
+ .text
+ .globl foo
+ .type foo, @function
+foo:
+ leaq EXTERNAL_SYM(%rip), %rdi
+ .hidden EXTERNAL_SYM
diff --git a/ld/testsuite/ld-x86-64/pr24905.t b/ld/testsuite/ld-x86-64/pr24905.t
new file mode 100644
index 0000000000..5e7dbd371f
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr24905.t
@@ -0,0 +1 @@
+PROVIDE_HIDDEN(EXTERNAL_SYM = ADDR(.text));
diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp
index d815e5d633..b13cc7df0e 100644
--- a/ld/testsuite/ld-x86-64/x86-64.exp
+++ b/ld/testsuite/ld-x86-64/x86-64.exp
@@ -458,6 +458,8 @@ run_dump_test "pr24458c"
run_dump_test "pr24458c-x32"
run_dump_test "pr24721"
run_dump_test "pr24721-x32"
+run_dump_test "pr24905"
+run_dump_test "pr24905-x32"
if { ![istarget "x86_64-*-linux*"] && ![istarget "x86_64-*-nacl*"]} {
return
--
2.20.1