arc: Don't generate dynamic relocation for non SEC_ALLOC sections
[deliverable/binutils-gdb.git] / bfd / elf64-x86-64.c
index 16e66f95d2c7b3cd5b79d670ad09cb9e8f59a040..183c8083464efee694695f6ed5d9695255326bb4 100644 (file)
@@ -1,5 +1,5 @@
 /* X86-64 specific support for ELF
-   Copyright (C) 2000-2019 Free Software Foundation, Inc.
+   Copyright (C) 2000-2020 Free Software Foundation, Inc.
    Contributed by Jan Hubicka <jh@suse.cz>.
 
    This file is part of BFD, the Binary File Descriptor library.
@@ -196,9 +196,6 @@ static reloc_howto_type x86_64_elf_howto_table[] =
        FALSE)
 };
 
-/* Set if a relocation is converted from a GOTPCREL relocation.  */
-#define R_X86_64_converted_reloc_bit (1 << 7)
-
 #define X86_PCREL_TYPE_P(TYPE)         \
   (   ((TYPE) == R_X86_64_PC8)         \
    || ((TYPE) == R_X86_64_PC16)                \
@@ -1223,7 +1220,8 @@ elf_x86_64_check_tls_transition (bfd *abfd,
 
     case R_X86_64_GOTPC32_TLSDESC:
       /* Check transition from GDesc access model:
-               leaq x@tlsdesc(%rip), %rax
+               leaq x@tlsdesc(%rip), %rax <--- LP64 mode.
+               rex leal x@tlsdesc(%rip), %eax <--- X32 mode.
 
         Make sure it's a leaq adding rip to a 32-bit offset
         into any register, although it's probably almost always
@@ -1233,7 +1231,8 @@ elf_x86_64_check_tls_transition (bfd *abfd,
        return FALSE;
 
       val = bfd_get_8 (abfd, contents + offset - 3);
-      if ((val & 0xfb) != 0x48)
+      val &= 0xfb;
+      if (val != 0x48 && (ABI_64_P (abfd) || val != 0x40))
        return FALSE;
 
       if (bfd_get_8 (abfd, contents + offset - 2) != 0x8d)
@@ -1244,13 +1243,26 @@ elf_x86_64_check_tls_transition (bfd *abfd,
 
     case R_X86_64_TLSDESC_CALL:
       /* Check transition from GDesc access model:
-               call *x@tlsdesc(%rax)
+               call *x@tlsdesc(%rax) <--- LP64 mode.
+               call *x@tlsdesc(%eax) <--- X32 mode.
        */
       if (offset + 2 <= sec->size)
        {
-         /* Make sure that it's a call *x@tlsdesc(%rax).  */
+         unsigned int prefix;
          call = contents + offset;
-         return call[0] == 0xff && call[1] == 0x10;
+         prefix = 0;
+         if (!ABI_64_P (abfd))
+           {
+             /* Check for call *x@tlsdesc(%eax).  */
+             if (call[0] == 0x67)
+               {
+                 prefix = 1;
+                 if (offset + 3 > sec->size)
+                   return FALSE;
+               }
+           }
+         /* Make sure that it's a call *x@tlsdesc(%rax).  */
+         return call[prefix] == 0xff && call[1 + prefix] == 0x10;
        }
 
       return FALSE;
@@ -1494,6 +1506,8 @@ elf_x86_64_convert_load_reloc (bfd *abfd,
   bfd_boolean no_overflow;
   bfd_boolean relocx;
   bfd_boolean to_reloc_pc32;
+  bfd_boolean abs_symbol;
+  bfd_boolean local_ref;
   asection *tsec;
   bfd_signed_vma raddend;
   unsigned int opcode;
@@ -1501,6 +1515,7 @@ elf_x86_64_convert_load_reloc (bfd *abfd,
   unsigned int r_type = *r_type_p;
   unsigned int r_symndx;
   bfd_vma roff = irel->r_offset;
+  bfd_vma abs_relocation;
 
   if (roff < (r_type == R_X86_64_REX_GOTPCRELX ? 3 : 2))
     return TRUE;
@@ -1544,6 +1559,9 @@ elf_x86_64_convert_load_reloc (bfd *abfd,
                   || no_overflow
                   || is_pic);
 
+  abs_symbol = FALSE;
+  abs_relocation = 0;
+
   /* Get the symbol referred to by the reloc.  */
   if (h == NULL)
     {
@@ -1554,8 +1572,13 @@ elf_x86_64_convert_load_reloc (bfd *abfd,
       if (isym->st_shndx == SHN_UNDEF)
        return TRUE;
 
+      local_ref = TRUE;
       if (isym->st_shndx == SHN_ABS)
-       tsec = bfd_abs_section_ptr;
+       {
+         tsec = bfd_abs_section_ptr;
+         abs_symbol = TRUE;
+         abs_relocation = isym->st_value;
+       }
       else if (isym->st_shndx == SHN_COMMON)
        tsec = bfd_com_section_ptr;
       else if (isym->st_shndx == SHN_X86_64_LCOMMON)
@@ -1571,9 +1594,11 @@ elf_x86_64_convert_load_reloc (bfd *abfd,
         GOTPCRELX relocations since we need to modify REX byte.
         It is OK convert mov with R_X86_64_GOTPCREL to
         R_X86_64_PC32.  */
-      bfd_boolean local_ref;
       struct elf_x86_link_hash_entry *eh = elf_x86_hash_entry (h);
 
+      abs_symbol = ABS_SYMBOL_P (h);
+      abs_relocation = h->root.u.def.value;
+
       /* NB: Also set linker_def via SYMBOL_REFERENCES_LOCAL_P.  */
       local_ref = SYMBOL_REFERENCES_LOCAL_P (link_info, h);
       if ((relocx || opcode == 0x8b)
@@ -1647,7 +1672,7 @@ elf_x86_64_convert_load_reloc (bfd *abfd,
   if (no_overflow)
     return TRUE;
 
-convert:
+ convert:
   if (opcode == 0xff)
     {
       /* We have "call/jmp *foo@GOTPCREL(%rip)".  */
@@ -1713,6 +1738,9 @@ convert:
 
       if (opcode == 0x8b)
        {
+         if (abs_symbol && local_ref)
+           to_reloc_pc32 = FALSE;
+
          if (to_reloc_pc32)
            {
              /* Convert "mov foo@GOTPCREL(%rip), %reg" to
@@ -1772,7 +1800,22 @@ convert:
             overflow when sign-extending imm32 to imm64.  */
          r_type = (rex & REX_W) != 0 ? R_X86_64_32S : R_X86_64_32;
 
-rewrite_modrm_rex:
+       rewrite_modrm_rex:
+         if (abs_relocation)
+           {
+             /* Check if R_X86_64_32S/R_X86_64_32 fits.  */
+             if (r_type == R_X86_64_32S)
+               {
+                 if ((abs_relocation + 0x80000000) > 0xffffffff)
+                   return TRUE;
+               }
+             else
+               {
+                 if (abs_relocation > 0xffffffff)
+                   return TRUE;
+               }
+           }
+
          bfd_put_8 (abfd, modrm, contents + roff - 1);
 
          if (rex)
@@ -1864,6 +1907,7 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
       const char *name;
       bfd_boolean size_reloc;
       bfd_boolean converted_reloc;
+      bfd_boolean no_dynreloc;
 
       r_symndx = htab->r_sym (rel->r_info);
       r_type = ELF32_R_TYPE (rel->r_info);
@@ -1968,6 +2012,10 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
            converted = TRUE;
        }
 
+      if (!_bfd_elf_x86_valid_reloc_p (sec, info, htab, rel, h, isym,
+                                      symtab_hdr, &no_dynreloc))
+       return FALSE;
+
       if (! elf_x86_64_tls_transition (info, abfd, sec, contents,
                                       symtab_hdr, sym_hashes,
                                       &r_type, GOT_UNKNOWN,
@@ -2014,12 +2062,26 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
 
            switch (r_type)
              {
-             default: tls_type = GOT_NORMAL; break;
-             case R_X86_64_TLSGD: tls_type = GOT_TLS_GD; break;
-             case R_X86_64_GOTTPOFF: tls_type = GOT_TLS_IE; break;
+             default:
+               tls_type = GOT_NORMAL;
+               if (h)
+                 {
+                   if (ABS_SYMBOL_P (h))
+                     tls_type = GOT_ABS;
+                 }
+               else if (isym->st_shndx == SHN_ABS)
+                 tls_type = GOT_ABS;
+               break;
+             case R_X86_64_TLSGD:
+               tls_type = GOT_TLS_GD;
+               break;
+             case R_X86_64_GOTTPOFF:
+               tls_type = GOT_TLS_IE;
+               break;
              case R_X86_64_GOTPC32_TLSDESC:
              case R_X86_64_TLSDESC_CALL:
-               tls_type = GOT_TLS_GDESC; break;
+               tls_type = GOT_TLS_GDESC;
+               break;
              }
 
            if (h != NULL)
@@ -2164,7 +2226,7 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
        case R_X86_64_PC32_BND:
        case R_X86_64_PC64:
        case R_X86_64_64:
-pointer:
+       pointer:
          if (eh != NULL && (sec->flags & SEC_CODE) != 0)
            eh->zero_undefweak |= 0x2;
          /* We are called after all symbols have been resolved.  Only
@@ -2229,9 +2291,10 @@ pointer:
            }
 
          size_reloc = FALSE;
-do_size:
-         if (NEED_DYNAMIC_RELOCATION_P (info, TRUE, h, sec, r_type,
-                                        htab->pointer_r_type))
+       do_size:
+         if (!no_dynreloc
+             && NEED_DYNAMIC_RELOCATION_P (info, TRUE, h, sec, r_type,
+                                           htab->pointer_r_type))
            {
              struct elf_dyn_relocs *p;
              struct elf_dyn_relocs **head;
@@ -2252,7 +2315,7 @@ do_size:
              /* If this is a global symbol, we count the number of
                 relocations we need for this symbol.  */
              if (h != NULL)
-               head = &eh->dyn_relocs;
+               head = &h->dyn_relocs;
              else
                {
                  /* Track dynamic relocs needed for local syms too.
@@ -2279,7 +2342,7 @@ do_size:
              p = *head;
              if (p == NULL || p->sec != sec)
                {
-                 bfd_size_type amt = sizeof *p;
+                 size_t amt = sizeof *p;
 
                  p = ((struct elf_dyn_relocs *)
                       bfd_alloc (htab->elf.dynobj, amt));
@@ -2336,7 +2399,7 @@ do_size:
 
   return TRUE;
 
-error_return:
+ error_return:
   if (elf_section_data (sec)->this_hdr.contents != contents)
     free (contents);
   sec->check_relocs_failed = 1;
@@ -2663,7 +2726,7 @@ elf_x86_64_relocate_section (bfd *output_bfd,
          switch (r_type)
            {
            default:
-bad_ifunc_reloc:
+           bad_ifunc_reloc:
              if (h->root.root.string)
                name = h->root.root.string;
              else
@@ -2687,7 +2750,7 @@ bad_ifunc_reloc:
                goto do_relocation;
              /* FALLTHROUGH */
            case R_X86_64_64:
-do_ifunc_pointer:
+           do_ifunc_pointer:
              if (rel->r_addend != 0)
                {
                  if (h->root.root.string)
@@ -2773,7 +2836,7 @@ do_ifunc_pointer:
            }
        }
 
-skip_ifunc:
+    skip_ifunc:
       resolved_to_zero = (eh != NULL
                          && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh));
 
@@ -2865,7 +2928,14 @@ skip_ifunc:
                              base_got->contents + off);
                  local_got_offsets[r_symndx] |= 1;
 
-                 if (bfd_link_pic (info))
+                 /* NB: GOTPCREL relocations against local absolute
+                    symbol store relocation value in the GOT slot
+                    without relative relocation.  */
+                 if (bfd_link_pic (info)
+                     && !(sym->st_shndx == SHN_ABS
+                          && (r_type == R_X86_64_GOTPCREL
+                              || r_type == R_X86_64_GOTPCRELX
+                              || r_type == R_X86_64_REX_GOTPCRELX)))
                    relative_reloc = TRUE;
                }
            }
@@ -3032,7 +3102,7 @@ skip_ifunc:
              break;
            }
 
-use_plt:
+       use_plt:
          if (h->plt.offset != (bfd_vma) -1)
            {
              if (htab->plt_second != NULL)
@@ -3147,7 +3217,7 @@ use_plt:
          /* FIXME: The ABI says the linker should make sure the value is
             the same when it's zeroextended to 64 bit.  */
 
-direct:
+       direct:
          if ((input_section->flags & SEC_ALLOC) == 0)
            break;
 
@@ -3160,7 +3230,7 @@ direct:
                                    && (X86_PCREL_TYPE_P (r_type)
                                        || X86_SIZE_TYPE_P (r_type)));
 
-         if (GENERATE_DYNAMIC_RELOCATION_P (info, eh, r_type,
+         if (GENERATE_DYNAMIC_RELOCATION_P (info, eh, r_type, sec,
                                             need_copy_reloc_in_pie,
                                             resolved_to_zero, FALSE))
            {
@@ -3358,7 +3428,7 @@ direct:
                          if (roff < 3
                              || (roff - 3 + 22) > input_section->size)
                            {
-corrupt_input:
+                           corrupt_input:
                              info->callbacks->einfo
                                (_("%F%P: corrupt input: %pB\n"),
                                 input_bfd);
@@ -3401,10 +3471,13 @@ corrupt_input:
                {
                  /* GDesc -> LE transition.
                     It's originally something like:
-                    leaq x@tlsdesc(%rip), %rax
+                    leaq x@tlsdesc(%rip), %rax <--- LP64 mode.
+                    rex leal x@tlsdesc(%rip), %eax <--- X32 mode.
 
                     Change it to:
-                    movl $x@tpoff, %rax.  */
+                    movq $x@tpoff, %rax <--- LP64 mode.
+                    rex movl $x@tpoff, %eax <--- X32 mode.
+                  */
 
                  unsigned int val, type;
 
@@ -3412,7 +3485,8 @@ corrupt_input:
                    goto corrupt_input;
                  type = bfd_get_8 (input_bfd, contents + roff - 3);
                  val = bfd_get_8 (input_bfd, contents + roff - 1);
-                 bfd_put_8 (output_bfd, 0x48 | ((type >> 2) & 1),
+                 bfd_put_8 (output_bfd,
+                            (type & 0x48) | ((type >> 2) & 1),
                             contents + roff - 3);
                  bfd_put_8 (output_bfd, 0xc7, contents + roff - 2);
                  bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
@@ -3426,11 +3500,30 @@ corrupt_input:
                {
                  /* GDesc -> LE transition.
                     It's originally:
-                    call *(%rax)
+                    call *(%rax) <--- LP64 mode.
+                    call *(%eax) <--- X32 mode.
                     Turn it into:
-                    xchg %ax,%ax.  */
-                 bfd_put_8 (output_bfd, 0x66, contents + roff);
-                 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
+                    xchg %ax,%ax <-- LP64 mode.
+                    nopl (%rax)  <-- X32 mode.
+                  */
+                 unsigned int prefix = 0;
+                 if (!ABI_64_P (input_bfd))
+                   {
+                     /* Check for call *x@tlsdesc(%eax).  */
+                     if (contents[roff] == 0x67)
+                       prefix = 1;
+                   }
+                 if (prefix)
+                   {
+                     bfd_put_8 (output_bfd, 0x0f, contents + roff);
+                     bfd_put_8 (output_bfd, 0x1f, contents + roff + 1);
+                     bfd_put_8 (output_bfd, 0x00, contents + roff + 2);
+                   }
+                 else
+                   {
+                     bfd_put_8 (output_bfd, 0x66, contents + roff);
+                     bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
+                   }
                  continue;
                }
              else if (r_type == R_X86_64_GOTTPOFF)
@@ -3741,13 +3834,18 @@ corrupt_input:
                {
                  /* GDesc -> IE transition.
                     It's originally something like:
-                    leaq x@tlsdesc(%rip), %rax
+                    leaq x@tlsdesc(%rip), %rax <--- LP64 mode.
+                    rex leal x@tlsdesc(%rip), %eax <--- X32 mode.
 
                     Change it to:
-                    movq x@gottpoff(%rip), %rax # before xchg %ax,%ax.  */
+                    # before xchg %ax,%ax in LP64 mode.
+                    movq x@gottpoff(%rip), %rax
+                    # before nopl (%rax) in X32 mode.
+                    rex movl x@gottpoff(%rip), %eax
+                 */
 
                  /* Now modify the instruction as appropriate. To
-                    turn a leaq into a movq in the form we use it, it
+                    turn a lea into a mov in the form we use it, it
                     suffices to change the second byte from 0x8d to
                     0x8b.  */
                  if (roff < 2)
@@ -3768,13 +3866,32 @@ corrupt_input:
                {
                  /* GDesc -> IE transition.
                     It's originally:
-                    call *(%rax)
+                    call *(%rax) <--- LP64 mode.
+                    call *(%eax) <--- X32 mode.
 
                     Change it to:
-                    xchg %ax, %ax.  */
+                    xchg %ax, %ax <-- LP64 mode.
+                    nopl (%rax)  <-- X32 mode.
+                  */
 
-                 bfd_put_8 (output_bfd, 0x66, contents + roff);
-                 bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
+                 unsigned int prefix = 0;
+                 if (!ABI_64_P (input_bfd))
+                   {
+                     /* Check for call *x@tlsdesc(%eax).  */
+                     if (contents[roff] == 0x67)
+                       prefix = 1;
+                   }
+                 if (prefix)
+                   {
+                     bfd_put_8 (output_bfd, 0x0f, contents + roff);
+                     bfd_put_8 (output_bfd, 0x1f, contents + roff + 1);
+                     bfd_put_8 (output_bfd, 0x00, contents + roff + 2);
+                   }
+                 else
+                   {
+                     bfd_put_8 (output_bfd, 0x66, contents + roff);
+                     bfd_put_8 (output_bfd, 0x90, contents + roff + 1);
+                   }
                  continue;
                }
              else
@@ -3969,12 +4086,12 @@ corrupt_input:
            }
        }
 
-do_relocation:
+    do_relocation:
       r = _bfd_final_link_relocate (howto, input_bfd, input_section,
                                    contents, rel->r_offset,
                                    relocation, rel->r_addend);
 
-check_relocation_error:
+    check_relocation_error:
       if (r != bfd_reloc_ok)
        {
          const char *name;
@@ -4397,7 +4514,7 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd,
       else
        {
          BFD_ASSERT((h->got.offset & 1) == 0);
-do_glob_dat:
+       do_glob_dat:
          bfd_put_64 (output_bfd, (bfd_vma) 0,
                      htab->elf.sgot->contents + h->got.offset);
          rela.r_info = htab->r_info (h->dynindx, R_X86_64_GLOB_DAT);
@@ -5429,8 +5546,8 @@ static const struct elf_x86_backend_data elf_x86_64_nacl_arch_bed =
 #define elf_backend_object_p                   elf64_x86_64_nacl_elf_object_p
 #undef elf_backend_modify_segment_map
 #define        elf_backend_modify_segment_map          nacl_modify_segment_map
-#undef elf_backend_modify_program_headers
-#define        elf_backend_modify_program_headers      nacl_modify_program_headers
+#undef elf_backend_modify_headers
+#define        elf_backend_modify_headers              nacl_modify_headers
 #undef elf_backend_final_write_processing
 #define elf_backend_final_write_processing     nacl_final_write_processing
 
@@ -5483,7 +5600,7 @@ elf32_x86_64_nacl_elf_object_p (bfd *abfd)
 #undef elf_backend_bfd_from_remote_memory
 #undef elf_backend_size_info
 #undef elf_backend_modify_segment_map
-#undef elf_backend_modify_program_headers
+#undef elf_backend_modify_headers
 #undef elf_backend_final_write_processing
 
 /* Intel L1OM support.  */
This page took 0.032338 seconds and 4 git commands to generate.