Put IRELATIVE relocations after JUMP_SLOT.
authorH.J. Lu <hjl.tools@gmail.com>
Fri, 21 Oct 2011 15:13:37 +0000 (15:13 +0000)
committerH.J. Lu <hjl.tools@gmail.com>
Fri, 21 Oct 2011 15:13:37 +0000 (15:13 +0000)
bfd/

2011-10-21  H.J. Lu  <hongjiu.lu@intel.com>

PR ld/13302
* elf32-i386.c (elf_i386_link_hash_table): Add next_jump_slot_index
and next_irelative_index.
(elf_i386_link_hash_table_create): Initialize next_jump_slot_index
and next_irelative_index.
(elf_i386_allocate_dynrelocs): Increment reloc_count instead of
next_tls_desc_index.
(elf_i386_size_dynamic_sections): Set next_tls_desc_index and
next_irelative_index from reloc_count.
(elf_i386_finish_dynamic_symbol): Put R_386_IRELATIVE after
R_386_JUMP_SLOT.

* elf64-x86-64.c (elf_x86_64_link_hash_table): Add
next_jump_slot_index and next_irelative_index.
(elf_x86_64_link_hash_table_create): Initialize
next_jump_slot_index and next_irelative_index.
(elf_x86_64_size_dynamic_sections): Set next_irelative_index
from reloc_count.
(elf_x86_64_finish_dynamic_symbol): Put R_X86_64_IRELATIVE after
R_X86_64_JUMP_SLOT.

ld/testsuite/

2011-10-21  H.J. Lu  <hongjiu.lu@intel.com>

PR ld/13302
* ld-ifunc/ifunc-16-i386.d: New.
* ld-ifunc/ifunc-16-x86-64.d: Likewise.
* ld-ifunc/ifunc-16-x86.s: Likewise.

bfd/ChangeLog
bfd/elf32-i386.c
bfd/elf64-x86-64.c
ld/testsuite/ChangeLog
ld/testsuite/ld-ifunc/ifunc-16-i386.d [new file with mode: 0644]
ld/testsuite/ld-ifunc/ifunc-16-x86-64.d [new file with mode: 0644]
ld/testsuite/ld-ifunc/ifunc-16-x86.s [new file with mode: 0644]

index 4bad00483533056e743a71c2035152971926724d..1a71b6d16abe8545f0c36913564f69eaeb1e4b10 100644 (file)
@@ -1,3 +1,26 @@
+2011-10-21  H.J. Lu  <hongjiu.lu@intel.com>
+
+       PR ld/13302
+       * elf32-i386.c (elf_i386_link_hash_table): Add next_jump_slot_index
+       and next_irelative_index.
+       (elf_i386_link_hash_table_create): Initialize next_jump_slot_index
+       and next_irelative_index.
+       (elf_i386_allocate_dynrelocs): Increment reloc_count instead of
+       next_tls_desc_index.
+       (elf_i386_size_dynamic_sections): Set next_tls_desc_index and
+       next_irelative_index from reloc_count.
+       (elf_i386_finish_dynamic_symbol): Put R_386_IRELATIVE after
+       R_386_JUMP_SLOT.
+
+       * elf64-x86-64.c (elf_x86_64_link_hash_table): Add
+       next_jump_slot_index and next_irelative_index.
+       (elf_x86_64_link_hash_table_create): Initialize
+       next_jump_slot_index and next_irelative_index.
+       (elf_x86_64_size_dynamic_sections): Set next_irelative_index
+       from reloc_count.
+       (elf_x86_64_finish_dynamic_symbol): Put R_X86_64_IRELATIVE after
+       R_X86_64_JUMP_SLOT.
+
 2011-10-20  Nick Clifton  <nickc@redhat.com>
 
        PR ld/13049
index 7ef1fc1ec5d73c1ed93b1f705fe104b5993a21ac..c3156bdb873a012b100b6e31053521e6cb65107e 100644 (file)
@@ -806,6 +806,12 @@ struct elf_i386_link_hash_table
 
   /* The index of the next unused R_386_TLS_DESC slot in .rel.plt.  */
   bfd_vma next_tls_desc_index;
+
+  /* The index of the next unused R_386_JUMP_SLOT slot in .rel.plt.  */
+  bfd_vma next_jump_slot_index;
+
+  /* The index of the next unused R_386_IRELATIVE slot in .rel.plt.  */
+  bfd_vma next_irelative_index;
 };
 
 /* Get the i386 ELF linker hash table from a link_info structure.  */
@@ -946,6 +952,8 @@ elf_i386_link_hash_table_create (bfd *abfd)
   ret->sym_cache.abfd = NULL;
   ret->srelplt2 = NULL;
   ret->tls_module_base = NULL;
+  ret->next_jump_slot_index = 0;
+  ret->next_irelative_index = 0;
 
   ret->loc_hash_table = htab_try_create (1024,
                                         elf_i386_local_htab_hash,
@@ -2275,7 +2283,7 @@ elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
 
          /* We also need to make an entry in the .rel.plt section.  */
          htab->elf.srelplt->size += sizeof (Elf32_External_Rel);
-         htab->next_tls_desc_index++;
+         htab->elf.srelplt->reloc_count++;
 
          if (get_elf_i386_backend_data (info->output_bfd)->is_vxworks
               && !info->shared)
@@ -2700,9 +2708,19 @@ elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
      incremented.  However, when we reserve space for TLS descriptors,
      it's not incremented, so in order to compute the space reserved
      for them, it suffices to multiply the reloc count by the jump
-     slot size.  */
+     slot size.
+     
+     PR ld/13302: We start next_irelative_index at the end of .rela.plt
+     so that R_386_IRELATIVE entries come last.  */
   if (htab->elf.srelplt)
-    htab->sgotplt_jump_table_size = htab->next_tls_desc_index * 4;
+    {
+      htab->next_tls_desc_index = htab->elf.srelplt->reloc_count;
+      htab->sgotplt_jump_table_size = htab->next_tls_desc_index * 4;
+      htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
+    }
+  else if (htab->elf.irelplt)
+    htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
+
 
   if (htab->elf.sgotplt)
     {
@@ -4364,13 +4382,13 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd,
 
       if (plt == htab->elf.splt)
        {
-         plt_index = h->plt.offset / plt_entry_size - 1;
-         got_offset = (plt_index + 3) * 4;
+         got_offset = h->plt.offset / plt_entry_size - 1;
+         got_offset = (got_offset + 3) * 4;
        }
       else
        {
-         plt_index = h->plt.offset / plt_entry_size;
-         got_offset = plt_index * 4;
+         got_offset = h->plt.offset / plt_entry_size;
+         got_offset = got_offset * 4;
        }
 
       /* Fill in the entry in the procedure linkage table.  */
@@ -4431,18 +4449,6 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd,
                       + abed->plt->plt_got_offset);
        }
 
-      /* Don't fill PLT entry for static executables.  */
-      if (plt == htab->elf.splt)
-       {
-         bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
-                     plt->contents + h->plt.offset
-                      + abed->plt->plt_reloc_offset);
-         bfd_put_32 (output_bfd, - (h->plt.offset
-                                     + abed->plt->plt_plt_offset + 4),
-                     plt->contents + h->plt.offset
-                      + abed->plt->plt_plt_offset);
-       }
-
       /* Fill in the entry in the global offset table.  */
       bfd_put_32 (output_bfd,
                  (plt->output_section->vma
@@ -4470,12 +4476,29 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd,
                       + h->root.u.def.section->output_offset),
                      gotplt->contents + got_offset);
          rel.r_info = ELF32_R_INFO (0, R_386_IRELATIVE);
+         /* R_386_IRELATIVE comes last.  */
+         plt_index = htab->next_irelative_index--;
        }
       else
-       rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
+       {
+         rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
+         plt_index = htab->next_jump_slot_index++;
+       }
       loc = relplt->contents + plt_index * sizeof (Elf32_External_Rel);
       bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
 
+      /* Don't fill PLT entry for static executables.  */
+      if (plt == htab->elf.splt)
+       {
+         bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
+                     plt->contents + h->plt.offset
+                      + abed->plt->plt_reloc_offset);
+         bfd_put_32 (output_bfd, - (h->plt.offset
+                                     + abed->plt->plt_plt_offset + 4),
+                     plt->contents + h->plt.offset
+                      + abed->plt->plt_plt_offset);
+       }
+
       if (!h->def_regular)
        {
          /* Mark the symbol as undefined, rather than as defined in
index e4c394615751bc3ba1bf0edf980b3d0355ffee1a..a850ce7bcdc2ffaed8d033a4079d3c9e57b22d7c 100644 (file)
@@ -698,6 +698,11 @@ struct elf_x86_64_link_hash_table
   /* The offset into sgot of the GOT entry used by the PLT entry
      above.  */
   bfd_vma tlsdesc_got;
+
+  /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt.  */
+  bfd_vma next_jump_slot_index;
+  /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt.  */
+  bfd_vma next_irelative_index;
 };
 
 /* Get the x86-64 ELF linker hash table from a link_info structure.  */
@@ -839,6 +844,8 @@ elf_x86_64_link_hash_table_create (bfd *abfd)
   ret->tls_ld_got.refcount = 0;
   ret->sgotplt_jump_table_size = 0;
   ret->tls_module_base = NULL;
+  ret->next_jump_slot_index = 0; 
+  ret->next_irelative_index = 0;
 
   if (ABI_64_P (abfd))
     {
@@ -2667,10 +2674,18 @@ elf_x86_64_size_dynamic_sections (bfd *output_bfd,
      incremented.  However, when we reserve space for TLS descriptors,
      it's not incremented, so in order to compute the space reserved
      for them, it suffices to multiply the reloc count by the jump
-     slot size.  */
+     slot size.
+
+     PR ld/13302: We start next_irelative_index at the end of .rela.plt
+     so that R_X86_64_IRELATIVE entries come last.  */
   if (htab->elf.srelplt)
-    htab->sgotplt_jump_table_size
-      = elf_x86_64_compute_jump_table_size (htab);
+    {
+      htab->sgotplt_jump_table_size
+       = elf_x86_64_compute_jump_table_size (htab);
+      htab->next_irelative_index = htab->elf.srelplt->reloc_count - 1;
+    }
+  else if (htab->elf.irelplt)
+    htab->next_irelative_index = htab->elf.irelplt->reloc_count - 1;
 
   if (htab->tlsdesc_plt)
     {
@@ -4205,13 +4220,13 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd,
 
       if (plt == htab->elf.splt)
        {
-         plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
-         got_offset = (plt_index + 3) * GOT_ENTRY_SIZE;
+         got_offset = h->plt.offset / PLT_ENTRY_SIZE - 1;
+         got_offset = (got_offset + 3) * GOT_ENTRY_SIZE;
        }
       else
        {
-         plt_index = h->plt.offset / PLT_ENTRY_SIZE;
-         got_offset = plt_index * GOT_ENTRY_SIZE;
+         got_offset = h->plt.offset / PLT_ENTRY_SIZE;
+         got_offset = got_offset * GOT_ENTRY_SIZE;
        }
 
       /* Fill in the entry in the procedure linkage table.  */
@@ -4233,17 +4248,6 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd,
                       - 6),
                  plt->contents + h->plt.offset + 2);
 
-      /* Don't fill PLT entry for static executables.  */
-      if (plt == htab->elf.splt)
-       {
-         /* Put relocation index.  */
-         bfd_put_32 (output_bfd, plt_index,
-                     plt->contents + h->plt.offset + 7);
-         /* Put offset for jmp .PLT0.  */
-         bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
-                     plt->contents + h->plt.offset + 12);
-       }
-
       /* Fill in the entry in the global offset table, initially this
         points to the pushq instruction in the PLT which is at offset 6.  */
       bfd_put_64 (output_bfd, (plt->output_section->vma
@@ -4267,11 +4271,25 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd,
          rela.r_addend = (h->root.u.def.value
                           + h->root.u.def.section->output_section->vma
                           + h->root.u.def.section->output_offset);
+         /* R_X86_64_IRELATIVE comes last.  */
+         plt_index = htab->next_irelative_index--;
        }
       else
        {
          rela.r_info = htab->r_info (h->dynindx, R_X86_64_JUMP_SLOT);
          rela.r_addend = 0;
+         plt_index = htab->next_jump_slot_index++;
+       }
+
+      /* Don't fill PLT entry for static executables.  */
+      if (plt == htab->elf.splt)
+       {
+         /* Put relocation index.  */
+         bfd_put_32 (output_bfd, plt_index,
+                     plt->contents + h->plt.offset + 7);
+         /* Put offset for jmp .PLT0.  */
+         bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
+                     plt->contents + h->plt.offset + 12);
        }
 
       bed = get_elf_backend_data (output_bfd);
index fc9caf927a5e29d0d738f952896ceb5862ff8a1b..8480fee44196f11410bcc3d25bfce9776f7f8748 100644 (file)
@@ -1,3 +1,10 @@
+2011-10-21  H.J. Lu  <hongjiu.lu@intel.com>
+
+       PR ld/13302
+       * ld-ifunc/ifunc-16-i386.d: New.
+       * ld-ifunc/ifunc-16-x86-64.d: Likewise.
+       * ld-ifunc/ifunc-16-x86.s: Likewise.
+
 2011-10-20  Alan Modra  <amodra@gmail.com>
 
        * ld-selective/selective.exp: Use check_gc_sections_available.
diff --git a/ld/testsuite/ld-ifunc/ifunc-16-i386.d b/ld/testsuite/ld-ifunc/ifunc-16-i386.d
new file mode 100644 (file)
index 0000000..8ae3d0a
--- /dev/null
@@ -0,0 +1,10 @@
+#source: ifunc-16-x86.s
+#ld: -shared -m elf_i386
+#as: --32
+#readelf: -r --wide
+#target: x86_64-*-* i?86-*-*
+
+Relocation section '.rel.plt' at .*
+[ ]+Offset[ ]+Info[ ]+Type[ ]+.*
+[0-9a-f]+[ ]+[0-9a-f]+[ ]+R_386_JUMP_SLOT[ ]+0+[ ]+ifunc
+[0-9a-f]+[ ]+[0-9a-f]+[ ]+R_386_IRELATIVE[ ]*
diff --git a/ld/testsuite/ld-ifunc/ifunc-16-x86-64.d b/ld/testsuite/ld-ifunc/ifunc-16-x86-64.d
new file mode 100644 (file)
index 0000000..d69626d
--- /dev/null
@@ -0,0 +1,10 @@
+#source: ifunc-16-x86.s
+#as: --64
+#ld: -shared -melf_x86_64
+#readelf: -r --wide
+#target: x86_64-*-*
+
+Relocation section '.rela.plt' at .*
+[ ]+Offset[ ]+Info[ ]+Type[ ]+.*
+[0-9a-f]+[ ]+[0-9a-f]+[ ]+R_X86_64_JUMP_SLOT[ ]+0+[ ]+ifunc \+ 0
+[0-9a-f]+[ ]+[0-9a-f]+[ ]+R_X86_64_IRELATIVE[ ]+[0-9a-f]*
diff --git a/ld/testsuite/ld-ifunc/ifunc-16-x86.s b/ld/testsuite/ld-ifunc/ifunc-16-x86.s
new file mode 100644 (file)
index 0000000..fb38253
--- /dev/null
@@ -0,0 +1,17 @@
+       .text
+       .globl  fct
+       .type   fct, @gnu_indirect_function
+       .set    fct,resolve
+       .hidden int_fct
+       .globl  int_fct
+       .set    int_fct,fct
+       .p2align 4,,15
+       .type   resolve, @function
+resolve:
+       call    ifunc@PLT
+       .size   resolve, .-resolve
+       .globl  g
+       .type   g, @function
+g:
+       jmp     int_fct@PLT
+       .size   g, .-g