From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f41.google.com (mail-wm1-f41.google.com [209.85.128.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 23AE4311969 for ; Sun, 26 Jul 2026 10:14:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.41 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785060848; cv=none; b=MxrxZISablDRdIwCdTHUAgkcy9pmv66SQRXB7wkO6TWqhXYba3bKpptI2V40Ty5+CCgSrktw7p2PUYWZE3a3gujq3bLhVdnURErbmLjzkK8x1NXe/pT8swXeysj70fDCz2QPWBMH4l7LXMsm+j9mwpxnLbUEMEof7aLXvjBXNxA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785060848; c=relaxed/simple; bh=h1P5btjzqqAMj2JC/X8BiIMgvZUoT0u7grKnwIzMGNc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hEs7uLznaXDr5UDysSEx1bjT+46CQmaVf+blklFlGVOZsAGft6671RwRUqhghuSER9/PFCzx0AB/ZOp5jOB2TwlMggv+ubhmgv5azFNelgjPL44xoFTU9UltLFX5pY+dPrVELGmV9hML1IRxUgRy/I7N9L3WH8qwqk/nu1wdm44= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=blackwall.org; spf=none smtp.mailfrom=blackwall.org; dkim=pass (2048-bit key) header.d=blackwall.org header.i=@blackwall.org header.b=DsAYRiII; arc=none smtp.client-ip=209.85.128.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=blackwall.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=blackwall.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=blackwall.org header.i=@blackwall.org header.b="DsAYRiII" Received: by mail-wm1-f41.google.com with SMTP id 5b1f17b1804b1-493b966dd74so11256615e9.3 for ; Sun, 26 Jul 2026 03:14:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=blackwall.org; s=google; t=1785060845; x=1785665645; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=xDxc0+6iV2GZQ0LIsObeEGPpkXqQEjGEB1+96GPkh0w=; b=DsAYRiII0z46xLMODLhdXX6FTdSWsC2IH1WKUXn1ajSMLETkWe8NRDXRbEGImqZMTK a8KMcZLcU/g2QQabFfa+Gs31/4xiqiSDSTS9i/xn4qoy4m6otZroS+yB/1e1xpStFkQU 3HGHb2mHOaueTALdzayGcNN83/N6MlIOaHcfr/132hd3IPlmbdEKTPBeEr8+YK+Z6jCi IuZ4cynlBtGMEmS9fT77yCsM1XSJHYq3zzTbT8tdCzl18QD1/nuLf1XM/hqlyyxWoHwy b94nfFq4Ce5lW2MYAOmeGK9o4mJGB7TC0BduductCmisk65yKWg9o5M25JHLjQ/5/65F E3Gw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785060845; x=1785665645; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=xDxc0+6iV2GZQ0LIsObeEGPpkXqQEjGEB1+96GPkh0w=; b=JWEe4I0lpXH3ZZVxr8kajQ5jYxNlAWpRKjLYI8b4cfc4QSEzqtZQoXXKcXC7S7Qw0B 6WgJDmd5vDXQaG+fmZ46nzPAjDcxICGTWVe5fEAYv5NTSZ3qhv9B3QXkyIMWILC+TqPy si0bj2+xyTsKpoaLeKhStlID3LQeivK9BoTD+/sGwhes7e1tJBD4+txpA5xY207BXXXl YvgTbq2w6/rcUxcJHGGIGS2JDLy9VMF6ppO/JZOnndPu+t4j6NIhLudjHjerCydpKIVc w+qgN5poU+B+1Nt9MX7aXOiqYp1f02sK/+5P6ECird5PyUZrXGjJtBzPNFF+b6rHv2O/ tMmQ== X-Forwarded-Encrypted: i=1; AHgh+RoE5Fxk1ydhy2kogFZihyOezPN9C89uovh1fCZ9G0ts6lWWMx1OZX9Q4Bwo4fFL7SsGi/nDh1M=@vger.kernel.org X-Gm-Message-State: AOJu0YylHf+oxu8qm0Fv71e7jwEsGZj31ZyOCCz/xi4uSyGAv/xbEPJ4 cy3oXRMkwM0//2eyqo4b2SnXOc7QiaQ/9IKrnL40uY1nX50E94ji+q+LdIkGoRr/XO4= X-Gm-Gg: AR+sD10KKnzPcr/dlqeK/ZVPnJYRCzOHENuDaJMZdNLUD9HYL3UKmzF1WSVnZkXKjvJ 5URNl4fSQVd7jcYw3jsa54HS/fUUO5QhxCAq97cCRpQK7LbyJ5RYNUvypx3mLJjZ3Mg9FElyykl u3DzXkVTgW1w+vDDDi6Cj5g7KH6rz/40e5vpVnm+ES/YrF5ko3iIHFJxP70diJi5v4e8yS48q8O Gl+QmgZx1QZljGX3N/qMADEkUlsonr303m+cUCR3+7PUllte/mrHfDEkqzqYbko3OZTnjBGwCTM gdPXwF6nqMyMIGNCvUG1E++rA0U9JZU1YdZ4Ioj1DaaoVuYk6dvAgMHbAgMqmWDT0rlxQllTxhA 4jXagdsrpV5taS5IRov46Z5UmeHwIshQt0tcInx1qGIjTz/zo4wBuyI+fPD+o5MS1VowP8nIBvM hzg/UJLKnY X-Received: by 2002:a05:600c:3e10:b0:495:6134:6d61 with SMTP id 5b1f17b1804b1-496b57160e7mr53193435e9.19.1785060845317; Sun, 26 Jul 2026 03:14:05 -0700 (PDT) Received: from localhost ([109.160.73.171]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4957f9928fdsm162079695e9.1.2026.07.26.03.14.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 26 Jul 2026 03:14:04 -0700 (PDT) Date: Sun, 26 Jul 2026 13:13:53 +0300 From: Nikolay Aleksandrov To: Ren Wei Cc: bridge@lists.linux.dev, netdev@vger.kernel.org, idosch@nvidia.com, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, horms@kernel.org, nbd@nbd.name, linus.luessing@c0d3.blue, vega@nebusec.ai, zhilinz@nebusec.ai Subject: Re: [PATCH net 1/1] net: bridge: stop fast-leave after deleting a port group Message-ID: References: <1cf0898872ef7c72d5f4c0304414a192c6dac591.1784707712.git.zhilinz@nebusec.ai> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1cf0898872ef7c72d5f4c0304414a192c6dac591.1784707712.git.zhilinz@nebusec.ai> On Fri, Jul 24, 2026 at 12:52:48AM +0800, Ren Wei wrote: > From: Zhiling Zou > > br_multicast_leave_group() iterates mp->ports with pp = &p->next in > its fast-leave path. After br_multicast_del_pg() removes p, > continuing the loop advances pp through the deleted entry. > > If multicast-to-unicast was enabled, the bridge can hold multiple port > groups for the same port and group with different source MAC > addresses. Once multicast-to-unicast is disabled, > br_port_group_equal() matches those entries by port only. A fast leave > can then delete one entry and continue from its stale next pointer, > leaving mp->ports pointing at a deleted port group. > > Fast leave only needs to remove one matching port group. Break after > br_multicast_del_pg() so the loop stops before dereferencing the > removed entry. > > Fixes: 6db6f0eae605 ("bridge: multicast to unicast") > Cc: stable@vger.kernel.org > Reported-by: Vega > Assisted-by: Codex:gpt-5.4 > Signed-off-by: Zhiling Zou > Signed-off-by: Ren Wei > --- > net/bridge/br_multicast.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c > index 6b3ac473fd22..00aa9b2879d6 100644 > --- a/net/bridge/br_multicast.c > +++ b/net/bridge/br_multicast.c > @@ -3687,6 +3687,7 @@ br_multicast_leave_group(struct net_bridge_mcast *brmctx, > > p->flags |= MDB_PG_FLAGS_FAST_LEAVE; > br_multicast_del_pg(mp, p, pp); > + break; > } > goto out; > } > -- > 2.43.0 > Yeah, all other places which use br_port_group_equal do exactly that Acked-by: Nikolay Aleksandrov