Re: [PATCH] elf: Replace tst-p_alignmod1-editX with a python script

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 26/01/2022 12:35, H.J. Lu wrote:
> On Wed, Jan 26, 2022 at 4:10 AM Adhemerval Zanella
> <adhemerval.zanella@linaro.org> wrote:
>>
>>
>>
>> On 26/01/2022 07:09, Florian Weimer wrote:
>>> * Adhemerval Zanella via Libc-alpha:
>>>
>>>> diff --git a/scripts/tst-elf-edit.py b/scripts/tst-elf-edit.py
>>>> new file mode 100644
>>>> index 0000000000..1fb9b8e0fe
>>>> --- /dev/null
>>>> +++ b/scripts/tst-elf-edit.py
>>>> @@ -0,0 +1,206 @@
>>>
>>>> +class Elf_Ehdr:
>>>> +    def __init__(self, e_ident):
>>>> +        endian, addr, off = elf_types_fmts(e_ident)
>>>> +        self.fmt = '{0}HHI{1}{2}{2}IHHHHHH'.format(endian, addr, off)
>>>> +        self.len = struct.calcsize(self.fmt)
>>>> +
>>>> +    def read(self, f):
>>>> +        buf = f.read(self.len)
>>>> +        if not buf:
>>>> +            error('{}: header too small'.format(f.name))
>>>
>>> I think you need to check len(buf) < self.len.
>>
>> Ack.
>>
>>>
>>>> +class Elf_Phdr:
>>>> +    def __init__(self, e_ident):
>>>> +        endian, addr, off = elf_types_fmts(e_ident)
>>>> +        self.ei_class = e_ident[EI_CLASS]
>>>> +        if self.ei_class == ELFCLASS32:
>>>> +            self.fmt = '{0}I{2}{1}{1}IIII'.format(endian, addr, off)
>>>> +        else:
>>>> +            self.fmt = '{0}II{2}{1}{1}QQQ'.format(endian, addr, off)
>>>> +        self.len = struct.calcsize(self.fmt)
>>>> +
>>>> +    def read(self, f):
>>>> +        buf = f.read(self.len)
>>>> +        if not buf:
>>>> +            error('{}: program header too small'.format(f.name))
>>>
>>> Here as well.
>>
>> Ack.
>>
>>>
>>> Rest looks okay.
>>
>> Thanks, I push it upstream with the above fixes installed.
> 
> I got
> 
> FAIL: elf/tst-p_align3
> 
> [hjl@gnu-tgl-2 build-x86_64-linux]$ cat elf/tst-p_align3.out
> /export/build/gnu/tools-build/glibc-cet-gitlab/build-x86_64-linux/elf/tst-p_align3:
> error while loading shared libraries:
> /export/build/gnu/tools-build/glibc-cet-gitlab/build-x86_64-linux/elf/tst-p_alignmod3.so:
> cannot change memory protections
> [hjl@gnu-tgl-2 build-x86_64-linux]$
> 
> Only p_align should be changed to 0x100.  But I  saw

I am not sure if this is related because tst-p_align3 and tst-alignmod3.so uses
LDFLAGS instead:

1644 $(objpfx)tst-align3: $(objpfx)tst-alignmod3.so
1645 ifeq (yes,$(have-fpie))
1646 CFLAGS-tst-align3.c += $(PIE-ccflag)
1647 endif
1648 LDFLAGS-tst-align3 += -Wl,-z,max-page-size=0x200000
1649 LDFLAGS-tst-alignmod3.so += -Wl,-z,max-page-size=0x200000
1650 $(objpfx)tst-alignmod3.so: $(libsupport)

And the patch only changed the way tst-p_align1 and tst-p_align2 modules were
changed.

> 
> @@ -5,24 +5,24 @@ There are 11 program headers, starting a
> 
>  Program Headers:
>    Type           Offset   VirtAddr           PhysAddr
> FileSiz  MemSiz   Flg Align
> -  LOAD           0x000000 0x0000000000000000 0x0000000000000000
> 0x000d38 0x000d38 R   0x200000
> -  LOAD           0x200000 0x0000000000200000 0x0000000000200000
> 0x0004c5 0x0004c5 R E 0x200000
> -  LOAD           0x400000 0x0000000000400000 0x0000000000400000
> 0x000340 0x000340 R   0x200000
> -  LOAD           0x400340 0x0000000000600340 0x0000000000600340
> 0x1ffcc4 0x1ffcd8 RW  0x200000
> -  DYNAMIC        0x400360 0x0000000000600360 0x0000000000600360
> 0x0001e0 0x0001e0 RW  0x8
> +  LOAD           0x000000 0x0000000000000000 0x0000000000000000
> 0x0008c8 0x0008c8 R   0x100
> +  LOAD           0x000900 0x0000000000000900 0x0000000000000900
> 0x000115 0x000115 R E 0x100
> +  LOAD           0x000b00 0x0000000000000b00 0x0000000000000b00
> 0x000098 0x000098 R   0x100
> +  LOAD           0x000c18 0x0000000000000c18 0x0000000000000c18
> 0x000200 0x000208 RW  0x100
> +  DYNAMIC        0x000c30 0x0000000000000c30 0x0000000000000c30
> 0x0001b0 0x0001b0 RW  0x8
>    NOTE           0x0002a8 0x00000000000002a8 0x00000000000002a8
> 0x000050 0x000050 R   0x8
>    NOTE           0x0002f8 0x00000000000002f8 0x00000000000002f8
> 0x000044 0x000044 R   0x4
>    GNU_PROPERTY   0x0002a8 0x00000000000002a8 0x00000000000002a8
> 0x000050 0x000050 R   0x8
> -  GNU_EH_FRAME   0x400118 0x0000000000400118 0x0000000000400118
> 0x000074 0x000074 R   0x4
> +  GNU_EH_FRAME   0x000b00 0x0000000000000b00 0x0000000000000b00
> 0x000024 0x000024 R   0x4
>    GNU_STACK      0x000000 0x0000000000000000 0x0000000000000000
> 0x000000 0x000000 RW  0x10
> -  GNU_RELRO      0x400340 0x0000000000600340 0x0000000000600340
> 0x000cc0 0x000cc0 R   0x1
> +  GNU_RELRO      0x000c18 0x0000000000000c18 0x0000000000000c18
> 0x0001e8 0x0001e8 R   0x1
> 
>   Section to Segment mapping:
>    Segment Sections...
> -   00     .note.gnu.property .note.gnu.build-id .note.ABI-tag .hash
> .gnu.hash .dynsym .dynstr .gnu.version .gnu.version_r .rela.dyn
> .rela.plt
> -   01     .init .plt .plt.got .plt.sec .text .fini
> -   02     .rodata .eh_frame_hdr .eh_frame
> -   03     .init_array .fini_array .data.rel.ro .dynamic .got .got.plt
> .data .bss
> +   00     .note.gnu.property .note.gnu.build-id .note.ABI-tag .hash
> .gnu.hash .dynsym .dynstr .gnu.version .gnu.version_r .rela.dyn
> +   01     .init .plt .plt.got .text .fini
> +   02     .eh_frame_hdr .eh_frame
> +   03     .init_array .fini_array .data.rel.ro .dynamic .got .got.plt .bss
>     04     .dynamic
>     05     .note.gnu.property
>     06     .note.gnu.build-id .note.ABI-tag
>