Re: [PATCH -tip v8 03/13] kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler()

From: Masami Hiramatsu
Date: Mon Jul 05 2021 - 06:03:36 EST


Hi Ingo,

On Mon, 5 Jul 2021 09:03:19 +0200
Ingo Molnar <mingo@xxxxxxxxxx> wrote:

>
> * Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
>
> > --- a/include/linux/kprobes.h
> > +++ b/include/linux/kprobes.h
> > @@ -197,15 +197,23 @@ extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
> > struct pt_regs *regs);
> > extern int arch_trampoline_kprobe(struct kprobe *p);
> >
> > +void kretprobe_trampoline(void);
> > +/*
> > + * Since some architecture uses structured function pointer,
> > + * use dereference_function_descriptor() to get real function address.
> > + */
> > +static nokprobe_inline void *kretprobe_trampoline_addr(void)
> > +{
> > + return dereference_kernel_function_descriptor(kretprobe_trampoline);
> > +}
>
> Could we please also make 'kretprobe_trampoline' harder to use
> accidentally, such by naming it appropriately?
>
> __kretprobe_trampoline would be a good first step I guess.

Good idea! Let me update it.

Thank you,



--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>