Re: [PATCH net v3 1/1] ip6_tunnel: Correct mistake in if statement.

[Jamie Gloudon <jamie.gloudon@gmx.fr>]

On Mon, Nov 07, 2022 at 10:58:13AM +0200, Leon Romanovsky wrote:
> On Mon, Nov 07, 2022 at 04:31:22AM -0400, Jamie Gloudon wrote:
> > Make sure t->dev->flags & IFF_UP is check first for logical reason.
> > 
> > Fixes: 6c1cb4393cc7 ("ip6_tunnel: fix ip6 tunnel lookup in collect_md
> > mode")
> > Signed-off-by: Jamie Gloudon <jamie.gloudon@gmx.fr>
> > ---
> >  net/ipv6/ip6_tunnel.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
> > index 2fb4c6ad7243..22c71f991bb7 100644
> > --- a/net/ipv6/ip6_tunnel.c
> > +++ b/net/ipv6/ip6_tunnel.c
> > @@ -162,7 +162,7 @@ ip6_tnl_lookup(struct net *net, int link,
> >  		return cand;
> >  
> >  	t = rcu_dereference(ip6n->collect_md_tun);
> > -	if (t && t->dev->flags & IFF_UP)
> > +	if (t && (t->dev->flags & IFF_UP))
> 
> While this change makes is less ambiguous for reader, the C precedence
> rules are clear and & evaluated before &&.
> https://en.cppreference.com/w/c/language/operator_precedence
> 
> There is nothing to fix here.
> 
> Thanks
> 
> >  		return t;
> >  
> >  	t = rcu_dereference(ip6n->tnls_wc[0]);
> > -- 
> > 2.28.0
> >
Thanks for taking the time to review the patch.