Re: [PATCH net-next] ipv4: ip_tunnel: Replace strcpy use with strscpy

From: Simon Horman
Date: Fri May 02 2025 - 05:38:56 EST


On Thu, May 01, 2025 at 05:51:08PM +0100, Ruben Wauters wrote:
> On Thu, 2025-05-01 at 16:39 +0100, Simon Horman wrote:
> > On Thu, May 01, 2025 at 02:23:00AM +0100, Ruben Wauters wrote:
> > > Use of strcpy is decpreated, replaces the use of strcpy with
> > > strscpy as
> > > recommended.
> > >
> > > I am aware there is an explicit bounds check above, however using
> > > strscpy protects against buffer overflows in any future code, and
> > > there
> > > is no good reason I can see to not use it.
> >
> > Thanks, I agree. This patch doesn't buy us safety. But it doesn't
> > lose
> > us anything. And allows the code to move towards best practice.
> >
> > One thing I notices is that this change is is inconsistent with the
> > call to
> > the 3-argument variant of strscpy a few lines above - it should also
> > be hte
> > 2-argument version. Maybe that could be changed too. Maybe in a
> > separate patch.
>
>
> I can remove the size parameter from the above strscpy to make it
> consistent in v2.
>
> > It is customary when making such changes to add a note that
> > strscpy() was chosen because the code expects a NUL-terminated string
> > without zero-padding. (Which is the case due to the call to
> > strcat().)
> > Perhaps you could add some text to the commit message of v2 of this
> > patch?
>
> Apologies, I wasn't aware of this, I can add the text to v2.
>
> Just a point of clarification I wanted to ask, for v2 of the patch,
> should I include the Reviewed-by tag below? or should I remove it as
> there has been changes?

I think you can include it unless the changes turn
out to be materially different to what has been discussed
in this thread.

But if in doubt, drop it.

>
>
> > > Signed-off-by: Ruben Wauters <rubenru09@xxxxxxx>
> >
> > Reviewed-by: Simon Horman <horms@xxxxxxxxxx>

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