Re-apply: commit
ca3fe95e469b9daec153caa2c90665f5daaec2b5
With copy relocation, address of protected data defined in the shared
library may be external. This patch adds extern_protected_data and
changes _bfd_elf_symbol_refs_local_p to return false for protected data
if extern_protected_data is true.
This patch will break building shared libraries with protected data
symbols using GCCs older than GCC 5 without the bug fix for
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65248
GCC backport request should be made in the GCC bug report above.
To get correct run-time behavior on Linux, glibc 2.22 or above are
required, which have the bug fix for
https://sourceware.org/bugzilla/show_bug.cgi?id=17711
Backports for glibc 2.21, 2.20, 2.19 and 2.18 are on hjl/pr17711/2.21,
hjl/pr17711/2.20, hjl/pr17711/2.19 and hjl/pr17711/2.18 branches,
respectively, at
https://sourceware.org/git/?p=glibc.git;a=summary
bfd/
PR ld/pr15228
PR ld/pr17709
* elf-bfd.h (elf_backend_data): Add extern_protected_data.
* elf32-i386.c (elf_backend_extern_protected_data): New.
Defined to 1.
* elf64-x86-64.c (elf_backend_extern_protected_data): Likewise.
* elflink.c (_bfd_elf_adjust_dynamic_copy): Don't error on
copy relocs against protected symbols if extern_protected_data
is true.
(_bfd_elf_symbol_refs_local_p): Don't return true on protected
non-function symbols if extern_protected_data is true.
* elfxx-target.h (elf_backend_extern_protected_data): New.
Default to 0.
(elfNN_bed): Initialize extern_protected_data with
elf_backend_extern_protected_data.
ld/testsuite/
PR ld/pr15228
PR ld/pr17709
* ld-i386/i386.exp (i386tests): Add a test for PR ld/17709.
* ld-i386/pr17709-nacl.rd: New file.
* ld-i386/pr17709.rd: Likewise.
* ld-i386/pr17709a.s: Likewise.
* ld-i386/pr17709b.s: Likewise.
* ld-i386/protected3.d: Updated.
* ld-i386/protected3.s: Likewise.
* ld-x86-64/pr17709-nacl.rd: New file.
* ld-x86-64/pr17709.rd: Likewise.
* ld-x86-64/pr17709a.s: Likewise.
* ld-x86-64/pr17709b.s: Likewise.
* ld-x86-64/protected3.d: Updated.
* ld-x86-64/protected3.s: Likewise.
* ld-x86-64/x86-64.exp (x86_64tests): Add a test for PR ld/17709.
+2015-04-10 H.J. Lu <hongjiu.lu@intel.com>
+
+ PR ld/pr15228
+ PR ld/pr17709
+ * elf-bfd.h (elf_backend_data): Add extern_protected_data.
+ * elf32-i386.c (elf_backend_extern_protected_data): New.
+ Defined to 1.
+ * elf64-x86-64.c (elf_backend_extern_protected_data): Likewise.
+ * elflink.c (_bfd_elf_adjust_dynamic_copy): Don't error on
+ copy relocs against protected symbols if extern_protected_data
+ is true.
+ (_bfd_elf_symbol_refs_local_p): Don't return true on protected
+ non-function symbols if extern_protected_data is true.
+ * elfxx-target.h (elf_backend_extern_protected_data): New.
+ Default to 0.
+ (elfNN_bed): Initialize extern_protected_data with
+ elf_backend_extern_protected_data.
+
2015-04-10 H.J. Lu <hongjiu.lu@intel.com>
* compress.c (bfd_compress_section_contents): Replace bfd_malloc
in length rather than sec->size in length, if sec->rawsize is
non-zero and smaller than sec->size. */
unsigned caches_rawsize : 1;
+
+ /* Address of protected data defined in the shared library may be
+ external, i.e., due to copy relocation. */
+ unsigned extern_protected_data : 1;
};
/* Information about reloc sections associated with a bfd_elf_section_data
#define elf_backend_want_plt_sym 0
#define elf_backend_got_header_size 12
#define elf_backend_plt_alignment 4
+#define elf_backend_extern_protected_data 1
/* Support RELA for objdump of prelink objects. */
#define elf_info_to_howto elf_i386_info_to_howto_rel
#define elf_backend_got_header_size (GOT_ENTRY_SIZE*3)
#define elf_backend_rela_normal 1
#define elf_backend_plt_alignment 4
+#define elf_backend_extern_protected_data 1
#define elf_info_to_howto elf_x86_64_info_to_howto
/* Increment the size of DYNBSS to make room for the symbol. */
dynbss->size += h->size;
- if (h->protected_def)
+ /* No error if extern_protected_data is true. */
+ if (h->protected_def
+ && !get_elf_backend_data (dynbss->owner)->extern_protected_data)
info->callbacks->einfo
(_("%P: copy reloc against protected `%T' is dangerous\n"),
h->root.root.string);
bed = get_elf_backend_data (hash_table->dynobj);
- /* STV_PROTECTED non-function symbols are local. */
- if (!bed->is_function_type (h->type))
+ /* If extern_protected_data is false, STV_PROTECTED non-function
+ symbols are local. */
+ if (!bed->extern_protected_data && !bed->is_function_type (h->type))
return TRUE;
/* Function pointer equality tests may require that STV_PROTECTED
#ifndef elf_backend_caches_rawsize
#define elf_backend_caches_rawsize 0
#endif
+#ifndef elf_backend_extern_protected_data
+#define elf_backend_extern_protected_data 0
+#endif
#ifndef elf_backend_stack_align
#define elf_backend_stack_align 16
#endif
elf_backend_want_dynbss,
elf_backend_want_p_paddr_set_to_zero,
elf_backend_default_execstack,
- elf_backend_caches_rawsize
+ elf_backend_caches_rawsize,
+ elf_backend_extern_protected_data
};
/* Forward declaration for use when initialising alternative_target field. */
+2015-04-10 H.J. Lu <hongjiu.lu@intel.com>
+
+ PR ld/pr15228
+ PR ld/pr17709
+ * ld-i386/i386.exp (i386tests): Add a test for PR ld/17709.
+ * ld-i386/pr17709-nacl.rd: New file.
+ * ld-i386/pr17709.rd: Likewise.
+ * ld-i386/pr17709a.s: Likewise.
+ * ld-i386/pr17709b.s: Likewise.
+ * ld-i386/protected3.d: Updated.
+ * ld-i386/protected3.s: Likewise.
+ * ld-x86-64/pr17709-nacl.rd: New file.
+ * ld-x86-64/pr17709.rd: Likewise.
+ * ld-x86-64/pr17709a.s: Likewise.
+ * ld-x86-64/pr17709b.s: Likewise.
+ * ld-x86-64/protected3.d: Updated.
+ * ld-x86-64/protected3.s: Likewise.
+ * ld-x86-64/x86-64.exp (x86_64tests): Add a test for PR ld/17709.
+
2015-04-10 H.J. Lu <hongjiu.lu@intel.com>
PR ld/18223
"--32" {pr17306b.s} {} ""}
{"PR ld/17306 (2)" "-melf_i386 -shared -Bsymbolic --just-symbols=tmpdir/pr17306b.o" ""
"--32" {pr17306a.s} {} "libpr17306.so"}
+ {"PR ld/17709 (1)" "-melf_i386 -shared" ""
+ "--32" {pr17709a.s} {} "libpr17709.so"}
+ {"PR ld/17709 (2)" "-melf_i386 tmpdir/libpr17709.so" ""
+ "--32" {pr17709b.s} {{readelf -r pr17709.rd}} "pr17709"}
}
# So as to avoid rewriting every last test case here in a nacl variant,
--- /dev/null
+
+Relocation section '.rel\..*' at offset .* contains 1 entries:
+ Offset Info Type Sym\.Value Sym\. Name
+[0-9a-f ]+R_386_COPY +[0-9a-f]+ +foo
--- /dev/null
+
+Relocation section '.rel\..*' at offset .* contains 1 entries:
+ Offset Info Type Sym\.Value Sym\. Name
+[0-9a-f ]+R_386_COPY +[0-9a-f]+ +foo
--- /dev/null
+ .protected foo
+.globl foo
+ .data
+ .align 4
+ .type foo, @object
+ .size foo, 4
+foo:
+ .long 1
--- /dev/null
+ .text
+ .globl _start
+ .type _start, @function
+_start:
+ movl foo, %eax
Disassembly of section .text:
0+[a-f0-9]+ <bar>:
-[ ]*[a-f0-9]+: 8b 81 [a-f0-9][a-f0-9] [a-f0-9][a-f0-9] 00 00 mov 0x[a-f0-9]+\(%ecx\),%eax
+[ ]*[a-f0-9]+: 8b 81 [a-f0-9][a-f0-9] [a-f0-9][a-f0-9] ff ff mov -0x[a-f0-9]+\(%ecx\),%eax
+[ ]*[a-f0-9]+: 8b 00 mov \(%eax\),%eax
[ ]*[a-f0-9]+: c3 ret
#pass
.globl bar
.type bar, @function
bar:
- movl foo@GOTOFF(%ecx), %eax
+ movl foo@GOT(%ecx), %eax
+ movl (%eax), %eax
ret
.size bar, .-bar
--- /dev/null
+
+Relocation section '.rela\..*' at offset .* contains 1 entries:
+ +Offset +Info +Type +Symbol's Value +Symbol's Name \+ Addend
+[0-9a-f ]+R_X86_64_COPY+[0-9a-f ]+ +foo \+ 0
--- /dev/null
+
+Relocation section '.rela\..*' at offset .* contains 1 entries:
+ +Offset +Info +Type +Symbol's Value +Symbol's Name \+ Addend
+[0-9a-f ]+R_X86_64_COPY+[0-9a-f ]+ +foo \+ 0
--- /dev/null
+ .protected foo
+.globl foo
+ .data
+ .align 4
+ .type foo, @object
+ .size foo, 4
+foo:
+ .long 1
--- /dev/null
+ .text
+ .globl _start
+ .type _start, @function
+_start:
+ movl foo, %eax
Disassembly of section .text:
0+[a-f0-9]+ <bar>:
-[ ]*[a-f0-9]+: 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%eax # [a-f0-9]+ <foo>
+[ ]*[a-f0-9]+: 48 8b 05 ([0-9a-f]{2} ){4} * mov 0x[a-f0-9]+\(%rip\),%rax # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ ]*[a-f0-9]+: 8b 00 mov \(%rax\),%eax
[ ]*[a-f0-9]+: c3 retq *
#pass
.globl bar
.type bar, @function
bar:
- movl foo(%rip), %eax
+ movq foo@GOTPCREL(%rip), %rax
+ movl (%rax), %eax
ret
.size bar, .-bar
"--64" {pr17306b.s} {} ""}
{"PR ld/17306 (2)" "-melf_x86_64 -shared -Bsymbolic --just-symbols=tmpdir/pr17306b.o" ""
"--64" {pr17306a.s} {} "libpr17306.so"}
+ {"PR ld/17709 (1)" "-melf_x86_64 -shared" ""
+ "--64" {pr17709a.s} {} "libpr17709.so"}
+ {"PR ld/17709 (2)" "-melf_x86_64 tmpdir/libpr17709.so" ""
+ "--64" {pr17709b.s} {{readelf -rW pr17709.rd}} "pr17709"}
}
# So as to avoid rewriting every last test case here in a nacl variant,