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[committed, PATCH] PR ld/20244: Subtract GOT base only with a base register
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: binutils at sourceware dot org
- Date: Sat, 11 Jun 2016 21:25:08 -0700
- Subject: [committed, PATCH] PR ld/20244: Subtract GOT base only with a base register
- Authentication-results: sourceware.org; auth=none
When relocating R_386_GOT32 in "op $0, bar@GOT", we shouldn't subtract
GOT base without a base register and we should disallow it without a
base register for PIC.
bfd/
PR ld/20244
* elf32-i386.c (elf_i386_relocate_section): When relocating
R_386_GOT32, return error without a base register for PIC and
subtract the .got.plt section address only with a base register.
ld/
PR ld/20244
* testsuite/ld-i386/i386.exp: Run pr20244-1a and pr20244-1b.
* testsuite/ld-i386/pr20244-1.s: New file.
* testsuite/ld-i386/pr20244-1a.d: Likewise.
* testsuite/ld-i386/pr20244-1b.d: Likewise.
* testsuite/ld-i386/pr20244-1c.d: Likewise.
---
bfd/ChangeLog | 7 +++++++
bfd/elf32-i386.c | 36 ++++++++++++++++++++++++++++++++----
ld/ChangeLog | 9 +++++++++
ld/testsuite/ld-i386/i386.exp | 3 +++
ld/testsuite/ld-i386/pr20244-1.s | 17 +++++++++++++++++
ld/testsuite/ld-i386/pr20244-1a.d | 26 ++++++++++++++++++++++++++
ld/testsuite/ld-i386/pr20244-1b.d | 11 +++++++++++
ld/testsuite/ld-i386/pr20244-1c.d | 4 ++++
8 files changed, 109 insertions(+), 4 deletions(-)
create mode 100644 ld/testsuite/ld-i386/pr20244-1.s
create mode 100644 ld/testsuite/ld-i386/pr20244-1a.d
create mode 100644 ld/testsuite/ld-i386/pr20244-1b.d
create mode 100644 ld/testsuite/ld-i386/pr20244-1c.d
diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 67b9778..b9c3a73 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,10 @@
+2016-06-11 H.J. Lu <hongjiu.lu@intel.com>
+
+ PR ld/20244
+ * elf32-i386.c (elf_i386_relocate_section): When relocating
+ R_386_GOT32, return error without a base register for PIC and
+ subtract the .got.plt section address only with a base register.
+
2016-06-10 Alan Modra <amodra@gmail.com>
* elf-strtab.c (struct strtab_save): Use size_t for "size".
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index 38c0520..7e2b2cb 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -4208,10 +4208,38 @@ r_386_got32:
if (off >= (bfd_vma) -2)
abort ();
- relocation = htab->elf.sgot->output_section->vma
- + htab->elf.sgot->output_offset + off
- - htab->elf.sgotplt->output_section->vma
- - htab->elf.sgotplt->output_offset;
+ relocation = (htab->elf.sgot->output_section->vma
+ + htab->elf.sgot->output_offset + off);
+ if ((*(contents + rel->r_offset - 1) & 0xc7) == 0x5)
+ {
+ if (bfd_link_pic (info))
+ {
+ /* For PIC, disallow R_386_GOT32 without a base
+ register since we don't know what the GOT base
+ is. */
+ const char *name;
+
+ if (h == NULL)
+ name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym,
+ NULL);
+ else
+ name = h->root.root.string;
+
+ (*_bfd_error_handler)
+ (_("%B: direct GOT relocation R_386_GOT32 against `%s' without base register can not be used when making a shared object"),
+ input_bfd, name);
+ bfd_set_error (bfd_error_bad_value);
+ return FALSE;
+ }
+ }
+ else
+ {
+ /* Subtract the .got.plt section address only with a base
+ register. */
+ relocation -= (htab->elf.sgotplt->output_section->vma
+ + htab->elf.sgotplt->output_offset);
+ }
+
break;
case R_386_GOTOFF:
diff --git a/ld/ChangeLog b/ld/ChangeLog
index 234bf05..4a74c8f 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,12 @@
+2016-06-11 H.J. Lu <hongjiu.lu@intel.com>
+
+ PR ld/20244
+ * testsuite/ld-i386/i386.exp: Run pr20244-1a and pr20244-1b.
+ * testsuite/ld-i386/pr20244-1.s: New file.
+ * testsuite/ld-i386/pr20244-1a.d: Likewise.
+ * testsuite/ld-i386/pr20244-1b.d: Likewise.
+ * testsuite/ld-i386/pr20244-1c.d: Likewise.
+
2016-06-08 Senthil Kumar Selvaraj <senthil_kumar.selvaraj@atmel.com>
PR ld/20221
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index f6cbe43..a6efa53 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -400,6 +400,9 @@ run_dump_test "undefweaka"
run_dump_test "undefweakb"
run_dump_test "pr19539"
run_dump_test "pr20117"
+run_dump_test "pr20244-1a"
+run_dump_test "pr20244-1b"
+run_dump_test "pr20244-1c"
if { !([istarget "i?86-*-linux*"]
|| [istarget "i?86-*-gnu*"]
diff --git a/ld/testsuite/ld-i386/pr20244-1.s b/ld/testsuite/ld-i386/pr20244-1.s
new file mode 100644
index 0000000..f22ce62
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr20244-1.s
@@ -0,0 +1,17 @@
+ .data
+ .type bar, @object
+bar:
+ .byte 1
+ .size bar, .-bar
+ .globl foo
+ .type foo, @object
+foo:
+ .byte 1
+ .size foo, .-foo
+ .text
+ .globl _start
+ .type _start, @function
+_start:
+ movl $0, bar@GOT
+ cmpl $0, foo@GOT
+ movl $bar@GOT, %ecx
diff --git a/ld/testsuite/ld-i386/pr20244-1a.d b/ld/testsuite/ld-i386/pr20244-1a.d
new file mode 100644
index 0000000..46ae4be
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr20244-1a.d
@@ -0,0 +1,26 @@
+#source: pr20244-1.s
+#as: --32
+#ld: -m elf_i386
+#objdump: --sym -dw
+#notarget: i?86-*-nacl* x86_64-*-nacl*
+
+.*: +file format .*
+
+SYMBOL TABLE:
+#...
+0+80490a0 l O .data 00000001 bar
+#...
+0+8048074 g F .text 00000000 _start
+#...
+0+80490a1 g O .data 00000001 foo
+#...
+
+
+
+Disassembly of section .text:
+
+0+8048074 <_start>:
+ +[a-f0-9]+: c7 05 8c 90 04 08 00 00 00 00 movl \$0x0,0x804908c
+ +[a-f0-9]+: 83 3d 90 90 04 08 00 cmpl \$0x0,0x8049090
+ +[a-f0-9]+: b9 f8 ff ff ff mov \$0xfffffff8,%ecx
+#pass
diff --git a/ld/testsuite/ld-i386/pr20244-1b.d b/ld/testsuite/ld-i386/pr20244-1b.d
new file mode 100644
index 0000000..d8ac4aa
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr20244-1b.d
@@ -0,0 +1,11 @@
+#source: pr20244-1.s
+#as: --32
+#ld: -m elf_i386
+#objdump: -s -j .got
+#notarget: i?86-*-nacl* x86_64-*-nacl*
+
+.*: +file format .*
+
+Contents of section .got:
+ 804908c a0900408 a1900408 +........ +
+#pass
diff --git a/ld/testsuite/ld-i386/pr20244-1c.d b/ld/testsuite/ld-i386/pr20244-1c.d
new file mode 100644
index 0000000..c670507
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr20244-1c.d
@@ -0,0 +1,4 @@
+#source: pr20244-1.s
+#as: --32
+#ld: -pie -m elf_i386
+#error: direct GOT relocation R_386_GOT32 against `bar' without base register can not be used when making a shared object
--
2.5.5