On Mon, Jan 8, 2018 at 7:06 AM, Jakub Jelinek <ja...@redhat.com> wrote:
> On Mon, Jan 08, 2018 at 07:00:11AM -0800, H.J. Lu wrote:
>> See:
>>
>> https://sourceware.org/ml/binutils/2017-11/msg00369.html
>
> Program Headers:
>   Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
>   LOAD           0x000000 0x00000000 0x00000000 0x00200 0x00200 R   0x200000
>   LOAD           0x000fd0 0x00200fd0 0x00200fd0 0x0002b 0x0002b R E 0x200000
>   LOAD           0x001000 0x00201000 0x00201000 0x00058 0x00058 R   0x200000
>   LOAD           0x200f80 0x00400f80 0x00400f80 0x000a0 0x000a0 RW  0x200000
>   DYNAMIC        0x200f80 0x00400f80 0x00400f80 0x00080 0x00080 RW  0x4
>   GNU_STACK      0x000000 0x00000000 0x00000000 0x00000 0x00000 RW  0x10
>   GNU_RELRO      0x200f80 0x00400f80 0x00400f80 0x00080 0x00080 R   0x1
>
> Uh, 3 read-only LOADs instead of 2?  Shouldn't then all the read-only
> non-executable sections be emitted together, so that you have a R, then R E,
> then RW PT_LOADs?

It is done on purpose since the second RO segment will be merged with the RELRO
segment at load time:

Elf file type is EXEC (Executable file)
Entry point 0x401ea0
There are 11 program headers, starting at offset 52

Program Headers:
  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
  PHDR           0x000034 0x00400034 0x00400034 0x00160 0x00160 R   0x4
  INTERP         0x000194 0x00400194 0x00400194 0x0001a 0x0001a R   0x1
      [Requesting program interpreter: /libx32/ld-linux-x32.so.2]
  LOAD           0x000000 0x00400000 0x00400000 0x0037c 0x0037c R   0x1000
  LOAD           0x000e68 0x00401e68 0x00401e68 0x00195 0x00195 R E 0x1000
  LOAD           0x001000 0x00402000 0x00402000 0x00124 0x00124 R   0x1000
  LOAD           0x001ef0 0x00402ef0 0x00402ef0 0x00134 0x00138 RW  0x1000
  DYNAMIC        0x001ef8 0x00402ef8 0x00402ef8 0x000f8 0x000f8 RW  0x4
  NOTE           0x0001b0 0x004001b0 0x004001b0 0x00044 0x00044 R   0x4
  GNU_EH_FRAME   0x001008 0x00402008 0x00402008 0x00034 0x00034 R   0x4
  GNU_STACK      0x000000 0x00000000 0x00000000 0x00000 0x00000 RW  0x10
  GNU_RELRO      0x001ef0 0x00402ef0 0x00402ef0 0x00110 0x00110 R   0x1

 Section to Segment mapping:
  Segment Sections...
   00
   01     .interp
   02     .interp .note.ABI-tag .note.gnu.build-id .gnu.hash .dynsym
.dynstr .gnu.version .gnu.version_r .rela.dyn .rela.plt
   03     .init .plt .text .fini
   04     .rodata .eh_frame_hdr .eh_frame
   05     .init_array .fini_array .dynamic .got .got.plt .data .bss
   06     .dynamic
   07     .note.ABI-tag .note.gnu.build-id
   08     .eh_frame_hdr
   09
   10     .init_array .fini_array .dynamic .got



-- 
H.J.

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