Linux userland exec

I need a C library which lets me exec() a statically linked binary, without invoking the execve() system call. The reason why the system call wouldn't work is that the binary file is not executable, and it's not possible to make it executable on that system. For dynamically linked binaries, running /lib/ld-linux.so.2 progname does the trick, but that segfaults on my statically linked binary.

I've found ul_exec 1.1 on http://archive.cert.uni-stuttgart.de/bugtraq/2004/01/msg00002.html , but that seems to segfault for its own H开发者_StackOverflow中文版ello, World binary on my system.

One option would be to make a copy of the binary, make the copy executable, and call execve(). I'm looking for a solution which doesn't need such a copy (because of performance reasons).

I've updated The Grugq's userland exec to work with modern x86 Linuxes. I wrote an x86_64 userland exec from scratch.

then how about a usermode filesystem (using python-fuse for example) that maps the execute bit to any file specified? would that be too much of a performance hit?

There is a good short wiki article with some not-completely-production-ready implementations: http://plash.beasts.org/wiki/UserModeExec