[PATCH 1/2] No-exec support for ppc64

[Paul Mackerras]

Jake Moilanen writes:

> diff -puN fs/binfmt_elf.c~nx-user-ppc64 fs/binfmt_elf.c
> --- linux-2.6-bk/fs/binfmt_elf.c~nx-user-ppc64	2005-03-08 16:08:54 -06:00
> +++ linux-2.6-bk-moilanen/fs/binfmt_elf.c	2005-03-08 16:08:54 -06:00
> @@ -99,6 +99,8 @@ static int set_brk(unsigned long start, 
>  		up_write(&current->mm->mmap_sem);
>  		if (BAD_ADDR(addr))
>  			return addr;
> +
> +  		sys_mprotect(start, end-start, PROT_READ|PROT_WRITE|PROT_EXEC);

I don't think I can push that upstream.  What happens if you leave
that out?

More generally, we are making a user-visible change, even for programs
that aren't marked as having non-executable stack or heap, because we
are now enforcing that the program can't execute from mappings that
don't have PROT_EXEC.  Perhaps we should enforce the requirement for
execute permission only on those programs that indicate somehow that
they can handle it?

Paul.