Re: sys_execve leaking rbp/rbx/r12-15 to the new process?

[Ingo Molnar]

* Denys Vlasenko <dvlasenk@xxxxxxxxxx> wrote:

> We can do this instead:
> 
> ENTRY(stub_execve)
>         CFI_STARTPROC
>         call	sys_execve
> 	testl	%eax, %eax
> 	jz	1f
> 	ret
> 1:      addq	$8, %rsp
> 	xorl	%ebx, %ebx    // maybe create a macro for zeroing these
> 	xorl	%ebp, %ebp    //
> 	xorl	%r12d, %r12d  //
> 	xorl	%r13d, %r13d  //
> 	xorl	%r14d, %r14d  //
> 	xorl	%r15d, %r15d  //

Yeah, call it ZERO_EXTRA_REGS or so.

> Any reason we should not do this change?

Not that I can see - lets try it.

Thanks,

	Ingo
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