x86: Fix DT_JMPREL/DT_PLTRELSZ when relocs share a section

If a linker script does not place the PLT relocations and "normal"
relocations in separate ELF sections, `ld` will currently output incorrect
values for DT_JMPREL and DT_PLTRELSZ - they cover the entire ELF section,
rather than just the PLT relocations

Don't ignore the extent of the BFD section - use the size of the srelplt
BFD section and its offset from the output_secttion

bfd/

	PR ld/30787
	* elfxx-x86.c (_bfd_x86_elf_finish_dynamic_sections): Use input
	section for DT_JMPREL and DT_PLTRELSZ.

ld/

	PR ld/30787
	* testsuite/ld-i386/i386.exp: Run pr30787.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.
	* testsuite/ld-i386/pr30787.d: New file.
	* testsuite/ld-i386/pr30787.s: Likewise.
	* testsuite/ld-i386/pr30787.t: Likewise.
	* testsuite/ld-x86-64/pr30787.d: Likewise.
	* testsuite/ld-x86-64/pr30787.s: Likewise.
	* testsuite/ld-x86-64/pr30787.t: Likewise.

bfd/elfxx-x86.c

@@ -2771,11 +2771,12 @@ _bfd_x86_elf_finish_dynamic_sections (bfd *output_bfd,
 	  break;
 
 	case DT_JMPREL:
-	  dyn.d_un.d_ptr = htab->elf.srelplt->output_section->vma;
+	  s = htab->elf.srelplt;
+	  dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
 	  break;
 
 	case DT_PLTRELSZ:
-	  s = htab->elf.srelplt->output_section;
+	  s = htab->elf.srelplt;
 	  dyn.d_un.d_val = s->size;
 	  break;
 

ld/testsuite/ld-i386/i386.exp

@@ -511,6 +511,7 @@ run_dump_test "dt-relr-1a"
 run_dump_test "dt-relr-1b"
 run_dump_test "pr28870"
 run_dump_test "pr28894"
+run_dump_test "pr30787"
 
 if { !([istarget "i?86-*-linux*"]
        || [istarget "i?86-*-gnu*"]

ld/testsuite/ld-i386/pr30787.d

@@ -0,0 +1,7 @@
+#as: --32
+#ld: -melf_i386 -shared --no-warn-rwx-segments -T pr30787.t
+#readelf: -d --wide
+
+#...
+ 0x0+2 \(PLTRELSZ\) +8 \(bytes\)
+#pass

ld/testsuite/ld-i386/pr30787.s

@@ -0,0 +1,6 @@
+	.text
+	.globl foo
+foo:
+	jmp	bar@PLT
+	leal	func@GOT(%ebx), %eax
+	.section .note.GNU-stack,"",@progbits

ld/testsuite/ld-i386/pr30787.t

@@ -0,0 +1,4 @@
+SECTIONS
+{
+  .rel.dyn : { *(.rel.*) }
+}

ld/testsuite/ld-x86-64/pr30787.d

@@ -0,0 +1,7 @@
+#as: --64
+#ld: -melf_x86_64 -shared --no-warn-rwx-segments -T pr30787.t
+#readelf: -d --wide
+
+#...
+ 0x0+2 \(PLTRELSZ\) +24 \(bytes\)
+#pass

ld/testsuite/ld-x86-64/pr30787.s

@@ -0,0 +1,6 @@
+	.text
+	.globl foo
+foo:
+	jmp	bar@PLT
+	movq	func@GOTPCREL(%rip), %rax
+	.section .note.GNU-stack,"",@progbits

ld/testsuite/ld-x86-64/pr30787.t

@@ -0,0 +1,4 @@
+SECTIONS
+{
+  .rela.dyn : { *(.rela.*) }
+}

ld/testsuite/ld-x86-64/x86-64.exp

@@ -505,6 +505,7 @@ run_dump_test "dt-relr-1a"
 run_dump_test "dt-relr-1a-x32"
 run_dump_test "dt-relr-1b"
 run_dump_test "dt-relr-1b-x32"
+run_dump_test "pr30787"
 
 if { ![skip_sframe_tests] } {
     run_dump_test "sframe-simple-1"