Re: [PATCH 11/18] kprobes: disable kretprobes with SCS

[Masami Hiramatsu]

On Fri, 18 Oct 2019 13:04:29 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> 
> [ Added Masami ]
> 
> On Fri, 18 Oct 2019 09:10:26 -0700
> Sami Tolvanen <samitolvanen@xxxxxxxxxx> wrote:
> 
> > With CONFIG_KRETPROBES, function return addresses are modified to
> > redirect control flow to kretprobe_trampoline. This is incompatible with
> > return address protection.
> > 
> > Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
> > ---
> >  arch/Kconfig | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/arch/Kconfig b/arch/Kconfig
> > index a222adda8130..4646e3b34925 100644
> > --- a/arch/Kconfig
> > +++ b/arch/Kconfig
> > @@ -171,7 +171,7 @@ config ARCH_USE_BUILTIN_BSWAP
> >  
> >  config KRETPROBES
> >  	def_bool y
> > -	depends on KPROBES && HAVE_KRETPROBES
> > +	depends on KPROBES && HAVE_KRETPROBES && ROP_PROTECTION_NONE
> 
> Again, this belongs in the arch code.

+1, below patch (from Steve) looks good to me.

Thank you,

> 
> -- Steve
> 
> >  
> >  config USER_RETURN_NOTIFIER
> >  	bool
> 
> 
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 41a9b4257b72..65557d7e6b5e 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -166,7 +166,7 @@ config ARM64
>  	select HAVE_STACKPROTECTOR
>  	select HAVE_SYSCALL_TRACEPOINTS
>  	select HAVE_KPROBES
> -	select HAVE_KRETPROBES
> +	select HAVE_KRETPROBES if ROP_PROTECTION_NONE
>  	select HAVE_GENERIC_VDSO
>  	select IOMMU_DMA if IOMMU_SUPPORT
>  	select IRQ_DOMAIN


-- 
Masami Hiramatsu <mhiramat@xxxxxxxxxx>