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    <p>PIE (and PIC) code needs a <em>relocation</em> process after loading at some address (different from default) and before it will be runned. I suggest you consult the code of <code>ld.so</code>. Also, you should check the relocations table in your binary (e.g. using <code>readelf -r</code>).</p> <p>Here is a good presentation on PIE (it is about OpenBSD, but the process is same). <a href="http://www.openbsd.org/papers/nycbsdcon08-pie/" rel="noreferrer">http://www.openbsd.org/papers/nycbsdcon08-pie/</a> or <a href="http://www.dcbsdcon.org/speakers/slides/miller_dcbsdcon2009.pdf" rel="noreferrer">http://www.dcbsdcon.org/speakers/slides/miller_dcbsdcon2009.pdf</a> </p> <p>I guess you should not only to change a GOT, but to also to find all Relocations and to do them.</p> <p>Basically, processing of PIE binary by ld.so is almost the same as processing a dynamic library with PIC, with relocating not a library, but the executable image itself.</p> <p>The "Wrong addresses" you see is a place, where an actual value would be written by relocation solving. As for i386 <a href="http://books.google.com/books?id=Id9cYsIdjIwC&amp;pg=PA174" rel="noreferrer">http://books.google.com/books?id=Id9cYsIdjIwC&amp;pg=PA174</a> there are relocations:</p> <ul> <li>R_386_GOTPC</li> <li>R_386_GOT32</li> <li>R_386_GOTOFF</li> <li>R_386_RELATIVE</li> </ul> <p>Linker should resolve all of them before the code can access a global data.</p> <p>Readelf -r sample:</p> <p>Dynamically linked one </p> <pre><code>$ readelf -r fdyn Relocation section '.rel.dyn' at offset 0x27c contains 1 entries: Offset Info Type Sym.Value Sym. Name 08049ff0 00000106 R_386_GLOB_DAT 00000000 __gmon_start__ Relocation section '.rel.plt' at offset 0x284 contains 2 entries: Offset Info Type Sym.Value Sym. Name 0804a000 00000107 R_386_JUMP_SLOT 00000000 __gmon_start__ 0804a004 00000207 R_386_JUMP_SLOT 00000000 __libc_start_main </code></pre> <p>PIE:</p> <pre><code>$ readelf -r fPIE Relocation section '.rel.dyn' at offset 0x388 contains 6 entries: Offset Info Type Sym.Value Sym. Name 00001fe8 00000008 R_386_RELATIVE 00001ff0 00000008 R_386_RELATIVE 00002010 00000008 R_386_RELATIVE 00001fe0 00000106 R_386_GLOB_DAT 00000000 __gmon_start__ 00001fe4 00000206 R_386_GLOB_DAT 00000000 _Jv_RegisterClasses 00001fec 00000406 R_386_GLOB_DAT 00000000 __cxa_finalize Relocation section '.rel.plt' at offset 0x3b8 contains 3 entries: Offset Info Type Sym.Value Sym. Name 00002000 00000107 R_386_JUMP_SLOT 00000000 __gmon_start__ 00002004 00000307 R_386_JUMP_SLOT 00000000 __libc_start_main 00002008 00000407 R_386_JUMP_SLOT 00000000 __cxa_finalize </code></pre>
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    1. COIf I link with -pie and -q specfied the linker generates a .rel.dyn section but I am not sure how to parse it. As well acording to readelf there is a .rel.text section (even if -pie is no specified) but that does not appear in the map file. Here is a (shortened) screen capture of readelf -r: Relocation section '.rel.dyn' at offset 0x8818 contains 78 entries: Offset Info Type Sym. Value Symbol's Name 00000018 00000017 R_ARM_RELATIVE 0000001c 00000017 R_ARM_RELATIVE 00000020 00000017 R_ARM_RELATIVE 00000000 00000402 R_ARM_ABS32 00000a88 _etext
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