On Mon, Jan 8, 2018 at 7:06 AM, Jakub Jelinek <[email protected]> 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.
