[src/trunk]: src/libexec/ld.elf_so/arch/i386 Get rid of RTLD_RELOCATE_SELF on...

[mycroft <mycroft%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b3d53f43453f
branches:  trunk
changeset: 536154:b3d53f43453f
user:      mycroft <mycroft%NetBSD.org@localhost>
date:      Mon Sep 09 14:08:07 2002 +0000

description:
Get rid of RTLD_RELOCATE_SELF on i386.
* Add a ld.so.script that exports _GOT_END_.
* Prebind the GOT in _rtld_start.
* Skip over GOT relocs in _rtld_relocate_nonplt_objects().
This makes debugging work better at least.

diffstat:

 libexec/ld.elf_so/arch/i386/Makefile.inc |    5 +-
 libexec/ld.elf_so/arch/i386/ld.so.script |  266 +++++++++++++++++++++++++++++++
 libexec/ld.elf_so/arch/i386/mdreloc.c    |   18 +-
 libexec/ld.elf_so/arch/i386/rtld_start.S |   18 +-
 4 files changed, 301 insertions(+), 6 deletions(-)

diffs (truncated from 348 to 300 lines):

diff -r 27715b9bd8de -r b3d53f43453f libexec/ld.elf_so/arch/i386/Makefile.inc
--- a/libexec/ld.elf_so/arch/i386/Makefile.inc  Mon Sep 09 13:19:28 2002 +0000
+++ b/libexec/ld.elf_so/arch/i386/Makefile.inc  Mon Sep 09 14:08:07 2002 +0000
@@ -1,10 +1,11 @@
-#      $NetBSD: Makefile.inc,v 1.5 2002/09/05 15:38:26 mycroft Exp $
+#      $NetBSD: Makefile.inc,v 1.6 2002/09/09 14:08:07 mycroft Exp $
 
 SRCS+= rtld_start.S mdreloc.c
 
 # XXX Should not be in CPPFLAGS!
 CPPFLAGS+= -fpic
 
-CPPFLAGS+= -DELFSIZE=32 -DRTLD_RELOCATE_SELF
+CPPFLAGS+= -DELFSIZE=32
 
 LDFLAGS+= -Bshareable -Bsymbolic -e .rtld_start
+LDFLAGS+= --script ${.CURDIR}/arch/i386/ld.so.script
diff -r 27715b9bd8de -r b3d53f43453f libexec/ld.elf_so/arch/i386/ld.so.script
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/libexec/ld.elf_so/arch/i386/ld.so.script  Mon Sep 09 14:08:07 2002 +0000
@@ -0,0 +1,266 @@
+OUTPUT_FORMAT("elf32-i386", "elf32-i386",
+             "elf32-i386")
+OUTPUT_ARCH(i386)
+ENTRY(_start)
+/* Do we need any of these for elf?
+   __DYNAMIC = 0;    */
+SECTIONS
+{
+  /* Read-only sections, merged into text segment: */
+  . = 0 + SIZEOF_HEADERS;
+  .hash          : { *(.hash)          }
+  .dynsym        : { *(.dynsym)                }
+  .dynstr        : { *(.dynstr)                }
+  .gnu.version   : { *(.gnu.version)   }
+  .gnu.version_d   : { *(.gnu.version_d)       }
+  .gnu.version_r   : { *(.gnu.version_r)       }
+  .rel.init      : { *(.rel.init)      }
+  .rela.init     : { *(.rela.init)     }
+  .rel.text      :
+    {
+      *(.rel.text)
+      *(.rel.text.*)
+      *(.rel.gnu.linkonce.t.*)
+    }
+  .rela.text     :
+    {
+      *(.rela.text)
+      *(.rela.text.*)
+      *(.rela.gnu.linkonce.t.*)
+    }
+  .rel.fini      : { *(.rel.fini)      }
+  .rela.fini     : { *(.rela.fini)     }
+  .rel.rodata    :
+    {
+      *(.rel.rodata)
+      *(.rel.rodata.*)
+      *(.rel.gnu.linkonce.r.*)
+    }
+  .rela.rodata   :
+    {
+      *(.rela.rodata)
+      *(.rela.rodata.*)
+      *(.rela.gnu.linkonce.r.*)
+    }
+  .rel.data      :
+    {
+      *(.rel.data)
+      *(.rel.data.*)
+      *(.rel.gnu.linkonce.d.*)
+    }
+  .rela.data     :
+    {
+      *(.rela.data)
+      *(.rela.data.*)
+      *(.rela.gnu.linkonce.d.*)
+    }
+  .rel.ctors     : { *(.rel.ctors)     }
+  .rela.ctors    : { *(.rela.ctors)    }
+  .rel.dtors     : { *(.rel.dtors)     }
+  .rela.dtors    : { *(.rela.dtors)    }
+  .rel.got       : { *(.rel.got)               }
+  .rela.got      : { *(.rela.got)              }
+  .rel.sdata     :
+    {
+      *(.rel.sdata)
+      *(.rel.sdata.*)
+      *(.rel.gnu.linkonce.s.*)
+    }
+  .rela.sdata     :
+    {
+      *(.rela.sdata)
+      *(.rela.sdata.*)
+      *(.rela.gnu.linkonce.s.*)
+    }
+  .rel.sbss      :
+    { 
+      *(.rel.sbss)
+      *(.rel.sbss.*)
+      *(.rel.gnu.linkonce.sb.*)
+    }
+  .rela.sbss     :
+    {
+      *(.rela.sbss)
+      *(.rela.sbss.*)
+      *(.rel.gnu.linkonce.sb.*)
+    }
+  .rel.sdata2    : 
+    { 
+      *(.rel.sdata2)
+      *(.rel.sdata2.*)
+      *(.rel.gnu.linkonce.s2.*)
+    }
+  .rela.sdata2   : 
+    {
+      *(.rela.sdata2)
+      *(.rela.sdata2.*)
+      *(.rela.gnu.linkonce.s2.*)
+    }
+  .rel.sbss2     : 
+    { 
+      *(.rel.sbss2)    
+      *(.rel.sbss2.*)
+      *(.rel.gnu.linkonce.sb2.*)
+    }
+  .rela.sbss2    : 
+    { 
+      *(.rela.sbss2)   
+      *(.rela.sbss2.*)
+      *(.rela.gnu.linkonce.sb2.*)
+    }
+  .rel.bss       : 
+    { 
+      *(.rel.bss)
+      *(.rel.bss.*)
+      *(.rel.gnu.linkonce.b.*)
+    }
+  .rela.bss      : 
+    { 
+      *(.rela.bss)
+      *(.rela.bss.*)
+      *(.rela.gnu.linkonce.b.*)
+    }
+  .rel.plt       : { *(.rel.plt)               }
+  .rela.plt      : { *(.rela.plt)              }
+  .init          : 
+  { 
+    KEEP (*(.init))
+  } =0x9090
+  .plt      : { *(.plt)        }
+  .text      :
+  {
+    *(.text)
+    *(.text.*)
+    *(.stub)
+    /* .gnu.warning sections are handled specially by elf32.em.  */
+    *(.gnu.warning)
+    *(.gnu.linkonce.t.*)
+  } =0x9090
+  .fini      :
+  {
+    KEEP (*(.fini))
+  } =0x9090
+  PROVIDE (__etext = .);
+  PROVIDE (_etext = .);
+  PROVIDE (etext = .);
+  .rodata   : { *(.rodata) *(.rodata.*) *(.gnu.linkonce.r.*) }
+  .rodata1   : { *(.rodata1) }
+  /* Adjust the address for the data segment.  We want to adjust up to
+     the same address within the page on the next page up.  */
+  . = ALIGN(8);
+  .data    :
+  {
+    *(.data)
+    *(.data.*)
+    *(.gnu.linkonce.d.*)
+    SORT(CONSTRUCTORS)
+  }
+  .data1   : { *(.data1) }
+  .eh_frame : { KEEP (*(.eh_frame)) }
+  .gcc_except_table : { *(.gcc_except_table) }
+  .ctors   : 
+  {
+    /* gcc uses crtbegin.o to find the start of
+       the constructors, so we make sure it is
+       first.  Because this is a wildcard, it
+       doesn't matter if the user does not
+       actually link against crtbegin.o; the
+       linker won't look for a file to match a
+       wildcard.  The wildcard also means that it
+       doesn't matter which directory crtbegin.o
+       is in.  */
+    KEEP (*crtbegin.o(.ctors))
+    /* We don't want to include the .ctor section from
+       from the crtend.o file until after the sorted ctors.
+       The .ctor section from the crtend file contains the
+       end of ctors marker and it must be last */
+    KEEP (*(EXCLUDE_FILE (*crtend.o ) .ctors))
+    KEEP (*(SORT(.ctors.*)))
+    KEEP (*(.ctors))
+  }
+   .dtors         :
+  {
+    KEEP (*crtbegin.o(.dtors))
+    KEEP (*(EXCLUDE_FILE (*crtend.o ) .dtors))
+    KEEP (*(SORT(.dtors.*)))
+    KEEP (*(.dtors))
+  }
+  .got           : { *(.got.plt) *(.got) }
+  PROVIDE (_GOT_END_ = .);
+  .sdata2   : { *(.sdata2) *(.sdata2.*) *(.gnu.linkonce.s2.*) }
+  .sbss2   : { *(.sbss2) *(.sbss2.*) *(.gnu.linkonce.sb2.*) }
+  .dynamic       : { *(.dynamic) }
+  /* We want the small data sections together, so single-instruction offsets
+     can access them all, and initialized data all before uninitialized, so
+     we can shorten the on-disk segment size.  */
+  .sdata     : 
+  {
+    *(.sdata) 
+    *(.sdata.*)
+    *(.gnu.linkonce.s.*)
+  }
+  _edata = .;
+  PROVIDE (edata = .);
+  __bss_start = .;
+  .sbss      :
+  {
+    PROVIDE (__sbss_start = .);
+    PROVIDE (___sbss_start = .);
+    *(.dynsbss)
+    *(.sbss)
+    *(.sbss.*)
+    *(.gnu.linkonce.sb.*)
+    *(.scommon)
+    PROVIDE (__sbss_end = .);
+    PROVIDE (___sbss_end = .);
+  }
+  .bss       :
+  {
+   *(.dynbss)
+   *(.bss)
+   *(.bss.*)
+   *(.gnu.linkonce.b.*)
+   *(COMMON)
+   /* Align here to ensure that the .bss section occupies space up to
+      _end.  Align after .bss to ensure correct alignment even if the
+      .bss section disappears because there are no input sections.  */
+   . = ALIGN(8);
+  }
+  . = ALIGN(8);
+  _end = .;
+  PROVIDE (end = .);
+  /* Stabs debugging sections.  */
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+  .stabstr 0 : { *(.stabstr) }
+  .stab.excl 0 : { *(.stab.excl) }
+  .stab.exclstr 0 : { *(.stab.exclstr) }
+  .stab.index 0 : { *(.stab.index) }
+  .stab.indexstr 0 : { *(.stab.indexstr) }
+  .comment 0 : { *(.comment) }
+  /* DWARF debug sections.
+     Symbols in the DWARF debugging sections are relative to the beginning
+     of the section so we begin them at 0.  */
+  /* DWARF 1 */
+  .debug          0 : { *(.debug) }
+  .line           0 : { *(.line) }
+  /* GNU DWARF 1 extensions */
+  .debug_srcinfo  0 : { *(.debug_srcinfo) }
+  .debug_sfnames  0 : { *(.debug_sfnames) }
+  /* DWARF 1.1 and DWARF 2 */
+  .debug_aranges  0 : { *(.debug_aranges) }
+  .debug_pubnames 0 : { *(.debug_pubnames) }
+  /* DWARF 2 */
+  .debug_info     0 : { *(.debug_info) *(.gnu.linkonce.wi.*) }
+  .debug_abbrev   0 : { *(.debug_abbrev) }
+  .debug_line     0 : { *(.debug_line) }
+  .debug_frame    0 : { *(.debug_frame) }
+  .debug_str      0 : { *(.debug_str) }
+  .debug_loc      0 : { *(.debug_loc) }
+  .debug_macinfo  0 : { *(.debug_macinfo) }
+  /* SGI/MIPS DWARF 2 extensions */
+  .debug_weaknames 0 : { *(.debug_weaknames) }
+  .debug_funcnames 0 : { *(.debug_funcnames) }
+  .debug_typenames 0 : { *(.debug_typenames) }
+  .debug_varnames  0 : { *(.debug_varnames) }
+  /* These must appear regardless of  .  */
+}
diff -r 27715b9bd8de -r b3d53f43453f libexec/ld.elf_so/arch/i386/mdreloc.c
--- a/libexec/ld.elf_so/arch/i386/mdreloc.c     Mon Sep 09 13:19:28 2002 +0000
+++ b/libexec/ld.elf_so/arch/i386/mdreloc.c     Mon Sep 09 14:08:07 2002 +0000
@@ -87,10 +87,22 @@
                        break;
 
                case R_TYPE(RELATIVE):
-                       *where += (Elf_Addr)obj->relocbase;
-                       rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path,
-                           (void *)*where));
+                   {
+                       extern Elf_Addr _GLOBAL_OFFSET_TABLE_[];
+                       extern Elf_Addr _GOT_END_[];