Re: Syscall security

Ingo Molnar
2003-09-26T14:10:29Z

On Fri, 26 Sep 2003, Maciej Zenczykowski wrote:

> The reason I'm asking is because I want to run totally untrusted
> statically linked binary code (automatically compiled from user
> submitted untrusted sources) which only needs read/write access to stdio
> which means it only requires syscalls read/write/exit + a few more for
> memory alloc/free (like brk) + a few more generated before main is
> called (execve and uname I believe).

if this syscall activity is so low then it might be much more flexible to
control the binary via ptrace and reject all but the desired syscalls.
This will cause a context switch but if it's stdio only then it's not a
big issue. Plus this would work on any existing Linux kernel.

Ingo