[Bug ld/18201] New: Incorrect ELF generated when .text is below 0x200000

[bijuabrahamp at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=18201

            Bug ID: 18201
           Summary: Incorrect ELF generated when .text is below 0x200000
           Product: binutils
           Version: 2.24
            Status: NEW
          Severity: normal
          Priority: P2
         Component: ld
          Assignee: unassigned at sourceware dot org
          Reporter: bijuabrahamp at gmail dot com

OS: Ubuntu 14.04, Fedora 21
ARCH : x86_64

Perform steps below to generate the incorrect ELF.

$ cat test.c 
int main()
{
int x = 3;
/* do something */
asm volatile("mov $60,%rax; mov $0,%rbx; syscall");
}


$ cat mylinker.lds 
SECTIONS
{
   . = 0x100000;
   .text : { *(.text) }
   . = 0x8000000;
   .data : { *(.data) }
   .bss : { *(.bss) }
}

$ gcc -c test.c
$ ld -T mylinker.lds test.o -o test

$ readelf -l test

Elf file type is EXEC (Executable file)
Entry point 0x100000
There are 2 program headers, starting at offset 64

Program Headers:
  Type           Offset             VirtAddr           PhysAddr
                 FileSiz            MemSiz              Flags  Align
  LOAD           0x0000000000000000 0x0000000000000000 0x0000000000000000
                 0x0000000000100060 0x0000000000100060  R E    200000
  GNU_STACK      0x0000000000000000 0x0000000000000000 0x0000000000000000
                 0x0000000000000000 0x0000000000000000  RW     10

Expected output :
  LOAD           0x0000000000100000 0x0000000000100000 0x0000000000000000
                 0x0000000000000060 0x0000000000000060  R E    200000


$ ./test
Killed

(Address 0 cannot be used by unprevileged users because of Linux kernel's 
mmap_min_addr)

Manually fixing up the ELF file using hex editor or some utilty resolves the
issue.

$ git clone https://github.com/bjxt/elf_fixup
$ cd elf_fixup
$ ./fixelf -e test -o 0x100000 -f 0x60 -v 0x100000 -m 0x60
$ ./test

Program completes successfully.

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