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From: Harald Hoyer <harald@redhat.com>
To: musl@lists.openwall.com
Subject: Re: [musl] [PATCH] Enable linking to a static position independent executable
Date: Tue, 25 Aug 2020 12:52:12 +0200	[thread overview]
Message-ID: <ce75b592-92f8-1449-72cd-8826ca8ec06e@redhat.com> (raw)
In-Reply-To: <20200427123207.1025966-1-harald@redhat.com>

Am 27.04.20 um 14:32 schrieb harald@redhat.com:
> From: Harald Hoyer <harald@redhat.com>
> 
> This also enables address space layout randomization (ASLR).
> 
> $ cat hello.c
> 
> int main()
> {
>   printf("main = 0x%lxd\n", main);
>   return 0;
> }
> 
> $ gcc -fPIE -static-pie -o hello hello.c -specs musl-gcc.specs
> 
> $ ldd hello
> 	statically linked
> 
> $ file hello
> hello: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), statically linked, with debug_info, not stripped, too many notes (256)
> 
> $ ./hello
> main = 0x7f858c4e72b9d
> 
> $ ./hello
> main = 0x7f0854d312b9d
> 
> $ ./hello
> main = 0x7f7179a1d2b9d
> 
> $ ./hello
> main = 0x7f37f981b2b9d
> 
> $ readelf -l hello
> 
> Elf file type is DYN (Shared object file)
> Entry point 0x104f
> There are 7 program headers, starting at offset 64
> 
> Program Headers:
>   Type           Offset             VirtAddr           PhysAddr
>                  FileSiz            MemSiz              Flags  Align
>   LOAD           0x0000000000000000 0x0000000000000000 0x0000000000000000
>                  0x0000000000000308 0x0000000000000308  R      0x1000
>   LOAD           0x0000000000001000 0x0000000000001000 0x0000000000001000
>                  0x0000000000003eb7 0x0000000000003eb7  R E    0x1000
>   LOAD           0x0000000000005000 0x0000000000005000 0x0000000000005000
>                  0x000000000000136c 0x000000000000136c  R      0x1000
>   LOAD           0x0000000000006e50 0x0000000000007e50 0x0000000000007e50
>                  0x00000000000002e0 0x00000000000009a0  RW     0x1000
>   DYNAMIC        0x0000000000006e70 0x0000000000007e70 0x0000000000007e70
>                  0x0000000000000180 0x0000000000000180  RW     0x8
>   GNU_STACK      0x0000000000000000 0x0000000000000000 0x0000000000000000
>                  0x0000000000000000 0x0000000000000000  RW     0x10
>   GNU_RELRO      0x0000000000006e50 0x0000000000007e50 0x0000000000007e50
>                  0x00000000000001b0 0x00000000000001b0  R      0x1
> 
>  Section to Segment mapping:
>   Segment Sections...
>    00     .hash .gnu.hash .dynsym .dynstr .rela.dyn
>    01     .init .plt .text .fini
>    02     .rodata .eh_frame
>    03     .init_array .fini_array .data.rel.ro .dynamic .got .got.plt .data .bss
>    04     .dynamic
>    05
>    06     .init_array .fini_array .data.rel.ro .dynamic .got
> ---
>  tools/musl-gcc.specs.sh | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>  mode change 100644 => 100755 tools/musl-gcc.specs.sh
> 
> diff --git a/tools/musl-gcc.specs.sh b/tools/musl-gcc.specs.sh
> old mode 100644
> new mode 100755
> index 30492574..ed584ed3
> --- a/tools/musl-gcc.specs.sh
> +++ b/tools/musl-gcc.specs.sh
> @@ -17,13 +17,13 @@ cat <<EOF
>  libgcc.a%s %:if-exists(libgcc_eh.a%s)
>  
>  *startfile:
> -%{!shared: $libdir/Scrt1.o} $libdir/crti.o crtbeginS.o%s
> +%{shared:;static-pie:$libdir/rcrt1.o; :$libdir/Scrt1.o} $libdir/crti.o crtbeginS.o%s
>  
>  *endfile:
>  crtendS.o%s $libdir/crtn.o
>  
>  *link:
> --dynamic-linker $ldso -nostdlib %{shared:-shared} %{static:-static} %{rdynamic:-export-dynamic}
> +-dynamic-linker $ldso -nostdlib %{shared:-shared} %{static:-static} %{static-pie:-static -pie --no-dynamic-linker} %{rdynamic:-export-dynamic}
>  
>  *esp_link:
>  
> 


Anythink missing? Does it need more work?


  parent reply	other threads:[~2020-08-25 10:52 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-06 18:07 [musl] [PATCH] V2 " harald
2020-04-06 22:04 ` Fangrui Song
2020-04-07  8:42   ` Szabolcs Nagy
2020-04-07 13:17   ` [musl] [PATCH] " harald
2020-04-23 11:59     ` Harald Hoyer
2020-04-24 15:08     ` Rich Felker
2020-04-27 12:24       ` Harald Hoyer
2020-04-27 12:32         ` harald
2020-05-08  9:05           ` Harald Hoyer
2020-08-25 10:52           ` Harald Hoyer [this message]
  -- strict thread matches above, loose matches on Subject: below --
2020-04-06 17:58 harald
2020-04-06 18:35 ` Harald Hoyer

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