[committed, PATCH] x86-64: Use .plt.bnd for IFUNC function address

[H.J. Lu]

When -z bndplt is used, we must use the .plt.bnd entry for IFUNC function
address.

bfd/

	PR ld/21481
	* elf64-x86-64.c (elf_x86_64_finish_dynamic_symbol): Use .plt.bnd
	for IFUNC function address.

ld/

	PR ld/21481
	* testsuite/ld-x86-64/pr21481a.c: New file.
	* testsuite/ld-x86-64/pr21481b.S: Likewise.
	* testsuite/ld-x86-64/x86-64.exp: Run PR ld/21481 tests.
---
 bfd/elf64-x86-64.c                | 14 ++++++++--
 ld/testsuite/ld-x86-64/pr21481a.c |  8 ++++++
 ld/testsuite/ld-x86-64/pr21481b.S | 56 +++++++++++++++++++++++++++++++++++++++
 ld/testsuite/ld-x86-64/x86-64.exp | 18 +++++++++++++
 4 files changed, 94 insertions(+), 2 deletions(-)
 create mode 100644 ld/testsuite/ld-x86-64/pr21481a.c
 create mode 100644 ld/testsuite/ld-x86-64/pr21481b.S

diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 1fbba1b..fb9336d 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -5974,6 +5974,7 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd,
 	  else
 	    {
 	      asection *plt;
+	      bfd_vma plt_offset;
 
 	      if (!h->pointer_equality_needed)
 		abort ();
@@ -5981,10 +5982,19 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd,
 	      /* For non-shared object, we can't use .got.plt, which
 		 contains the real function addres if we need pointer
 		 equality.  We load the GOT entry with the PLT entry.  */
-	      plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt;
+	      if (htab->plt_bnd != NULL)
+		{
+		  plt = htab->plt_bnd;
+		  plt_offset = eh->plt_bnd.offset;
+		}
+	      else
+		{
+		  plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt;
+		  plt_offset =  h->plt.offset;
+		}
 	      bfd_put_64 (output_bfd, (plt->output_section->vma
 				       + plt->output_offset
-				       + h->plt.offset),
+				       + plt_offset),
 			  htab->elf.sgot->contents + h->got.offset);
 	      return TRUE;
 	    }
diff --git a/ld/testsuite/ld-x86-64/pr21481a.c b/ld/testsuite/ld-x86-64/pr21481a.c
new file mode 100644
index 0000000..370275a
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr21481a.c
@@ -0,0 +1,8 @@
+extern void check (void);
+
+int
+main ()
+{
+  check ();
+  return 0;
+}
diff --git a/ld/testsuite/ld-x86-64/pr21481b.S b/ld/testsuite/ld-x86-64/pr21481b.S
new file mode 100644
index 0000000..744d86a
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr21481b.S
@@ -0,0 +1,56 @@
+	.section	.rodata.str1.1,"aMS",@progbits,1
+.LC0:
+	.string	"PASS"
+	.text
+	.globl	check
+	.type	check, @function
+check:
+	subq	$8, %rsp
+	call	*get_func1@GOTPCREL(%rip)
+	cmpl	$func1, %eax
+	jne	.L3
+	movq	func1_p@GOTPCREL(%rip), %rdx
+	cmpq	%rax, (%rdx)
+	jne	.L3
+	call	*func1@GOTPCREL(%rip)
+	cmpl	$1, %eax
+	jne	.L3
+	call	*call_func1@GOTPCREL(%rip)
+	cmpl	$1, %eax
+	jne	.L3
+	leaq	.LC0(%rip), %rdi
+	addq	$8, %rsp
+	jmp	*puts@GOTPCREL(%rip)
+.L3:
+	call	*abort@GOTPCREL(%rip)
+	.size	check, .-check
+	.globl	get_func1
+	.type	get_func1, @function
+get_func1:
+	movq	func1@GOTPCREL(%rip), %rax
+	ret
+	.size	get_func1, .-get_func1
+	.globl	call_func1
+	.type	call_func1, @function
+call_func1:
+	jmp	*func1@GOTPCREL(%rip)
+	.size	call_func1, .-call_func1
+	.globl	func1_p
+	.section	.rodata,"a",@progbits
+	.align 8
+	.size	func1_p, 8
+	.type	func1_p, @object
+func1_p:
+	.dc.a	func1
+	.text
+implementation1:
+	movl	$1, %eax
+	ret
+	.size	implementation1, .-implementation1
+	.globl	func1
+	.type	func1, @gnu_indirect_function
+func1:
+	leaq	implementation1(%rip), %rax
+	ret
+	.size	func1, .-func1
+	.section	.note.GNU-stack,"",@progbits
diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp
index 84cc7d7..61032aa 100644
--- a/ld/testsuite/ld-x86-64/x86-64.exp
+++ b/ld/testsuite/ld-x86-64/x86-64.exp
@@ -1316,6 +1316,24 @@ if { [isnative] && [which $CC] != 0 } {
 		"pr20800" \
 		"pass.out" \
 	    ] \
+	    [list \
+		"Run pr21481a" \
+		"$NOPIE_LDFLAGS -Wl,-z,bndplt" \
+		"" \
+		{ pr21481a.c pr21481b.S } \
+		"pr21481a" \
+		"pass.out" \
+		"$NOPIE_CFLAGS" \
+	    ] \
+	    [list \
+		"Run pr21481b" \
+		"$NOPIE_LDFLAGS -Wl,-z,bndplt,-z,now" \
+		"" \
+		{ pr21481a.c pr21481b.S } \
+		"pr21481b" \
+		"pass.out" \
+		"$NOPIE_CFLAGS" \
+	    ] \
 	]
     }
 
-- 
2.9.3