x86-64: Correct unwind info for the BND PLT

Since the BND PLT has

 230:	68 00 00 00 00       	pushq  $0x0
 235:	f2 e9 e5 ff ff ff    	bnd jmpq 220 <.plt>
 23b:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)

instead of

 230:	ff 25 e2 0d 20 00    	jmpq   *0x200de2(%rip)        # 201018
<func>
 236:	68 00 00 00 00       	pushq  $0x0
 23b:	e9 e0 ff ff ff       	jmpq   220 <.plt>

its unwind info should be

DW_CFA_def_cfa_expression (DW_OP_breg7 (rsp): 8; DW_OP_breg16 (rip): 0;
DW_OP_lit15; DW_OP_and; DW_OP_lit5; DW_OP_ge; DW_OP_lit3; DW_OP_shl;
DW_OP_plus)

bfd/

	PR ld/21038
	* elf64-x86-64.c (elf_x86_64_eh_frame_bnd_plt): New.
	(elf_x86_64_bnd_arch_bed): Use elf_x86_64_eh_frame_bnd_plt and
	elf_x86_64_eh_frame_plt_got.
	(elf_x86_64_size_dynamic_sections): Get unwind info from
	elf_x86_64_bnd_arch_bed for the BND PLT.

ld/

	PR ld/21038
	* testsuite/ld-x86-64/pr21038a.d: New file.
	* testsuite/ld-x86-64/pr21038a.s: Likewise.
	* testsuite/ld-x86-64/pr21038b.d: Likewise.
	* testsuite/ld-x86-64/pr21038b.s: Likewise.
	* testsuite/ld-x86-64/x86-64.exp: Run pr21038a and pr21038b.
This commit is contained in:
H.J. Lu 2017-01-11 09:16:44 -08:00
parent 4ad2da7317
commit 9e65917652
8 changed files with 217 additions and 6 deletions

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@ -1,3 +1,12 @@
2017-01-11 H.J. Lu <hongjiu.lu@intel.com>
PR ld/21038
* elf64-x86-64.c (elf_x86_64_eh_frame_bnd_plt): New.
(elf_x86_64_bnd_arch_bed): Use elf_x86_64_eh_frame_bnd_plt and
elf_x86_64_eh_frame_plt_got.
(elf_x86_64_size_dynamic_sections): Get unwind info from
elf_x86_64_bnd_arch_bed for the BND PLT.
2017-01-11 Jeremy Soller <jackpot51@gmail.com>
* config.bfd: Add entries for i686-redox and x86_64-redox.

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@ -659,6 +659,41 @@ static const bfd_byte elf_x86_64_eh_frame_plt[] =
DW_CFA_nop, DW_CFA_nop, DW_CFA_nop, DW_CFA_nop
};
/* .eh_frame covering the BND .plt section. */
static const bfd_byte elf_x86_64_eh_frame_bnd_plt[] =
{
PLT_CIE_LENGTH, 0, 0, 0, /* CIE length */
0, 0, 0, 0, /* CIE ID */
1, /* CIE version */
'z', 'R', 0, /* Augmentation string */
1, /* Code alignment factor */
0x78, /* Data alignment factor */
16, /* Return address column */
1, /* Augmentation size */
DW_EH_PE_pcrel | DW_EH_PE_sdata4, /* FDE encoding */
DW_CFA_def_cfa, 7, 8, /* DW_CFA_def_cfa: r7 (rsp) ofs 8 */
DW_CFA_offset + 16, 1, /* DW_CFA_offset: r16 (rip) at cfa-8 */
DW_CFA_nop, DW_CFA_nop,
PLT_FDE_LENGTH, 0, 0, 0, /* FDE length */
PLT_CIE_LENGTH + 8, 0, 0, 0, /* CIE pointer */
0, 0, 0, 0, /* R_X86_64_PC32 .plt goes here */
0, 0, 0, 0, /* .plt size goes here */
0, /* Augmentation size */
DW_CFA_def_cfa_offset, 16, /* DW_CFA_def_cfa_offset: 16 */
DW_CFA_advance_loc + 6, /* DW_CFA_advance_loc: 6 to __PLT__+6 */
DW_CFA_def_cfa_offset, 24, /* DW_CFA_def_cfa_offset: 24 */
DW_CFA_advance_loc + 10, /* DW_CFA_advance_loc: 10 to __PLT__+16 */
DW_CFA_def_cfa_expression, /* DW_CFA_def_cfa_expression */
11, /* Block length */
DW_OP_breg7, 8, /* DW_OP_breg7 (rsp): 8 */
DW_OP_breg16, 0, /* DW_OP_breg16 (rip): 0 */
DW_OP_lit15, DW_OP_and, DW_OP_lit5, DW_OP_ge,
DW_OP_lit3, DW_OP_shl, DW_OP_plus,
DW_CFA_nop, DW_CFA_nop, DW_CFA_nop, DW_CFA_nop
};
/* .eh_frame covering the .plt.got section. */
static const bfd_byte elf_x86_64_eh_frame_plt_got[] =
@ -770,11 +805,10 @@ static const struct elf_x86_64_backend_data elf_x86_64_bnd_arch_bed =
1+6, /* plt_got_insn_size */
11, /* plt_plt_insn_end */
0, /* plt_lazy_offset */
elf_x86_64_eh_frame_plt, /* eh_frame_plt */
sizeof (elf_x86_64_eh_frame_plt), /* eh_frame_plt_size */
/* FIXME: Needs .eh_frame coverage. */
NULL, /* eh_frame_plt_got */
0, /* eh_frame_plt_got_size */
elf_x86_64_eh_frame_bnd_plt, /* eh_frame_plt */
sizeof (elf_x86_64_eh_frame_bnd_plt), /* eh_frame_plt_size */
elf_x86_64_eh_frame_plt_got, /* eh_frame_plt_got */
sizeof (elf_x86_64_eh_frame_plt_got), /* eh_frame_plt_got_size */
};
#define elf_backend_arch_data &elf_x86_64_arch_bed
@ -3851,6 +3885,8 @@ elf_x86_64_size_dynamic_sections (bfd *output_bfd,
&& htab->elf.splt->size != 0
&& !bfd_is_abs_section (htab->elf.splt->output_section))
{
/* Unwind info for the BND PLT and the normal PLT have the
same time. */
const struct elf_x86_64_backend_data *arch_data
= get_elf_x86_64_arch_data (bed);
htab->plt_eh_frame->size = arch_data->eh_frame_plt_size;
@ -3939,8 +3975,12 @@ elf_x86_64_size_dynamic_sections (bfd *output_bfd,
if (htab->plt_eh_frame != NULL
&& htab->plt_eh_frame->contents != NULL)
{
/* Unwind info for the BND PLT and the normal PLT have the same
size, but different contents. */
const struct elf_x86_64_backend_data *arch_data
= get_elf_x86_64_arch_data (bed);
= (htab->plt_bnd != NULL
? &elf_x86_64_bnd_arch_bed
: get_elf_x86_64_arch_data (bed));
memcpy (htab->plt_eh_frame->contents,
arch_data->eh_frame_plt, htab->plt_eh_frame->size);
@ -3951,6 +3991,7 @@ elf_x86_64_size_dynamic_sections (bfd *output_bfd,
if (htab->plt_got_eh_frame != NULL
&& htab->plt_got_eh_frame->contents != NULL)
{
/* Unwind info for .plt.bnd and .plt.got sections are identical. */
const struct elf_x86_64_backend_data *arch_data
= get_elf_x86_64_arch_data (bed);

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@ -1,3 +1,12 @@
2017-01-11 H.J. Lu <hongjiu.lu@intel.com>
PR ld/21038
* testsuite/ld-x86-64/pr21038a.d: New file.
* testsuite/ld-x86-64/pr21038a.s: Likewise.
* testsuite/ld-x86-64/pr21038b.d: Likewise.
* testsuite/ld-x86-64/pr21038b.s: Likewise.
* testsuite/ld-x86-64/x86-64.exp: Run pr21038a and pr21038b.
2017-01-11 Jeremy Soller <jackpot51@gmail.com>
* configure.tgt: Add entries for x86-redox and x86_64-redox.

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@ -0,0 +1,71 @@
#name: PR ld/21038 (.plt.got)
#as: --64
#ld: -z bndplt -melf_x86_64 -shared -z relro --ld-generated-unwind-info
#objdump: -dw -Wf
.*: +file format .*
Contents of the .eh_frame section:
0+ 0000000000000014 00000000 CIE
Version: 1
Augmentation: "zR"
Code alignment factor: 1
Data alignment factor: -8
Return address column: 16
Augmentation data: 1b
DW_CFA_def_cfa: r7 \(rsp\) ofs 8
DW_CFA_offset: r16 \(rip\) at cfa-8
DW_CFA_nop
DW_CFA_nop
0+18 0000000000000014 0000001c FDE cie=00000000 pc=0000000000000238..0000000000000244
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
0+30 0000000000000024 00000034 FDE cie=00000000 pc=0000000000000220..0000000000000230
DW_CFA_def_cfa_offset: 16
DW_CFA_advance_loc: 6 to 0000000000000226
DW_CFA_def_cfa_offset: 24
DW_CFA_advance_loc: 10 to 0000000000000230
DW_CFA_def_cfa_expression \(DW_OP_breg7 \(rsp\): 8; DW_OP_breg16 \(rip\): 0; DW_OP_lit15; DW_OP_and; DW_OP_lit5; DW_OP_ge; DW_OP_lit3; DW_OP_shl; DW_OP_plus\)
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
0+58 0000000000000014 0000005c FDE cie=00000000 pc=0000000000000230..0000000000000238
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
Disassembly of section .plt:
0+220 <.plt>:
+[a-f0-9]+: ff 35 e2 0d 20 00 pushq 0x200de2\(%rip\) # 201008 <_GLOBAL_OFFSET_TABLE_\+0x8>
+[a-f0-9]+: f2 ff 25 e3 0d 20 00 bnd jmpq \*0x200de3\(%rip\) # 201010 <_GLOBAL_OFFSET_TABLE_\+0x10>
+[a-f0-9]+: 0f 1f 00 nopl \(%rax\)
Disassembly of section .plt.got:
0+230 <.plt.got>:
+[a-f0-9]+: f2 ff 25 c1 0d 20 00 bnd jmpq \*0x200dc1\(%rip\) # 200ff8 <func>
+[a-f0-9]+: 90 nop
Disassembly of section .text:
0+238 <foo>:
+[a-f0-9]+: e8 f3 ff ff ff callq 230 <.plt.got>
+[a-f0-9]+: 48 8b 05 b4 0d 20 00 mov 0x200db4\(%rip\),%rax # 200ff8 <func>
#pass

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@ -0,0 +1,8 @@
.text
.globl foo
.type foo, @function
foo:
.cfi_startproc
call func@plt
movq func@GOTPCREL(%rip), %rax
.cfi_endproc

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@ -0,0 +1,64 @@
#name: PR ld/21038 (.plt.bnd)
#as: --64
#ld: -z bndplt -melf_x86_64 -shared -z relro --ld-generated-unwind-info
#objdump: -dw -Wf
.*: +file format .*
Contents of the .eh_frame section:
0+ 0000000000000014 00000000 CIE
Version: 1
Augmentation: "zR"
Code alignment factor: 1
Data alignment factor: -8
Return address column: 16
Augmentation data: 1b
DW_CFA_def_cfa: r7 \(rsp\) ofs 8
DW_CFA_offset: r16 \(rip\) at cfa-8
DW_CFA_nop
DW_CFA_nop
0+18 0000000000000014 0000001c FDE cie=00000000 pc=0000000000000248..000000000000024d
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
0+30 0000000000000024 00000034 FDE cie=00000000 pc=0000000000000220..0000000000000240
DW_CFA_def_cfa_offset: 16
DW_CFA_advance_loc: 6 to 0000000000000226
DW_CFA_def_cfa_offset: 24
DW_CFA_advance_loc: 10 to 0000000000000230
DW_CFA_def_cfa_expression \(DW_OP_breg7 \(rsp\): 8; DW_OP_breg16 \(rip\): 0; DW_OP_lit15; DW_OP_and; DW_OP_lit5; DW_OP_ge; DW_OP_lit3; DW_OP_shl; DW_OP_plus\)
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
DW_CFA_nop
Disassembly of section .plt:
0+220 <.plt>:
+[a-f0-9]+: ff 35 e2 0d 20 00 pushq 0x200de2\(%rip\) # 201008 <_GLOBAL_OFFSET_TABLE_\+0x8>
+[a-f0-9]+: f2 ff 25 e3 0d 20 00 bnd jmpq \*0x200de3\(%rip\) # 201010 <_GLOBAL_OFFSET_TABLE_\+0x10>
+[a-f0-9]+: 0f 1f 00 nopl \(%rax\)
+[a-f0-9]+: 68 00 00 00 00 pushq \$0x0
+[a-f0-9]+: f2 e9 e5 ff ff ff bnd jmpq 220 <.plt>
+[a-f0-9]+: 0f 1f 44 00 00 nopl 0x0\(%rax,%rax,1\)
Disassembly of section .plt.bnd:
0+240 <func@plt>:
+[a-f0-9]+: f2 ff 25 d1 0d 20 00 bnd jmpq \*0x200dd1\(%rip\) # 201018 <func>
+[a-f0-9]+: 90 nop
Disassembly of section .text:
0+248 <foo>:
+[a-f0-9]+: e8 f3 ff ff ff callq 240 <func@plt>
#pass

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@ -0,0 +1,7 @@
.text
.globl foo
.type foo, @function
foo:
.cfi_startproc
call func@plt
.cfi_endproc

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@ -1021,3 +1021,5 @@ run_dump_test "pltgot-1"
run_dump_test "pltgot-2"
run_dump_test "pr20830a"
run_dump_test "pr20830b"
run_dump_test "pr21038a"
run_dump_test "pr21038b"