From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH] bridge: don't try to update timers in case of
 broken MLD queries
Date: Mon, 5 Aug 2013 15:42:22 -0700
Message-ID: <20130805154222.58361734@nehalam.linuxnetplumber.net>
References: <1375741925-22179-1-git-send-email-linus.luessing@web.de>
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Cc: Paul Bolle <pebolle@tiscali.nl>, Cong Wang <amwang@redhat.com>,
	netdev@vger.kernel.org, bridge@lists.linux-foundation.org,
	linux-kernel@vger.kernel.org, Adam Baker <linux@baker-net.org.uk>,
	"David S. Miller" <davem@davemloft.net>,
	Herbert Xu <herbert@gondor.apana.org.au>
To: Linus =?ISO-8859-1?B?TPxzc2luZw==?= <linus.luessing@web.de>
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On Tue,  6 Aug 2013 00:32:05 +0200
Linus L=FCssing <linus.luessing@web.de> wrote:

> Currently we are reading an uninitialized value for the max_delay
> variable when snooping an MLD query message of invalid length and would
> update our timers with that.
>=20
> Fixing this by simply ignoring such broken MLD queries (just like we do
> for IGMP already).
>=20
> This is a regression introduced by:
> "bridge: disable snooping if there is no querier" (b00589af3b04)
>=20
> Reported-by: Paul Bolle <pebolle@tiscali.nl>
> Signed-off-by: Linus L=FCssing <linus.luessing@web.de>
> ---
>  net/bridge/br_multicast.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>=20
> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
> index 61c5e81..08e576a 100644
> --- a/net/bridge/br_multicast.c
> +++ b/net/bridge/br_multicast.c
> @@ -1195,7 +1195,7 @@ static int br_ip6_multicast_query(struct net_bridge=
 *br,
>  		max_delay =3D msecs_to_jiffies(ntohs(mld->mld_maxdelay));
>  		if (max_delay)
>  			group =3D &mld->mld_mca;
> -	} else if (skb->len >=3D sizeof(*mld2q)) {
> +	} else {
>  		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
>  			err =3D -EINVAL;
>  			goto out;

Why not use else if here, other than that looks great.