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gccld

Does gcc have an -N option?

In "Learning Linux Binary Analysis" by Ryan "elfmaster" O'Neill.

Another neat trick that I just recently discovered during the construction of the Skeksi virus for 64-bit Linux is to merge the text and data segment into a single segment, that is, read+write+execute (RWX), by using the -N option with gcc.

I don't see an -N option in man gcc nor in gcc --help | grep '\-N'? Was this option renamed?

Solution

  • -N appears to be an option to (gnu)ld, the linker("loader")

    From man ld:

    -N --omagic Set the text and data sections to be readable and writable. Also, do not page-align the data segment, and disable linking against shared libraries. If the output format supports Unix style magic numbers, mark the output as "OMAGIC". Note: Although a writable text section is allowed for PE-COFF targets, it does not conform to the format specification published by Microsoft.

    Thegcc compiler-driver will pass options prepended with -Wl, to the loader, so your gcc-commandline will be something like:

    gcc -Wl,-N -oher_options...`