kernel-hardening - Re: [PATCH v3 18/20] x86/ftrace: Use vmalloc special flag

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Message-ID: <3cd659eb8c7d43cf46bebc6562c1c26bb6c51b51.camel@intel.com>
Date: Fri, 22 Feb 2019 00:55:49 +0000
From: "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To: "rostedt@...dmis.org" <rostedt@...dmis.org>
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Subject: Re: [PATCH v3 18/20] x86/ftrace: Use vmalloc special flag

On Thu, 2019-02-21 at 19:22 -0500, Steven Rostedt wrote:
> On Thu, 21 Feb 2019 15:44:49 -0800
> Rick Edgecombe <rick.p.edgecombe@...el.com> wrote:
> 
> > Use new flag VM_FLUSH_RESET_PERMS for handling freeing of special
> > permissioned memory in vmalloc and remove places where memory was set NX
> > and RW before freeing which is no longer needed.
> > 
> > Cc: Steven Rostedt <rostedt@...dmis.org>
> > Acked-by: Steven Rostedt (VMware) <rostedt@...dmis.org>
> > Signed-off-by: Rick Edgecombe <rick.p.edgecombe@...el.com>
> > ---
> >  arch/x86/kernel/ftrace.c | 6 ++----
> >  1 file changed, 2 insertions(+), 4 deletions(-)
> > 
> > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
> > index 13c8249b197f..93efe3955333 100644
> > --- a/arch/x86/kernel/ftrace.c
> > +++ b/arch/x86/kernel/ftrace.c
> > @@ -692,10 +692,6 @@ static inline void *alloc_tramp(unsigned long size)
> >  }
> >  static inline void tramp_free(void *tramp, int size)
> 
> As size is no longer used within the function, can you remove that too.
> 
> Thanks,
> 
> -- Steve
> 
Good point, I'll remove it.

Thanks,

Rick

[snip]

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