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Message-ID: <c945ebff-02fe-f2d5-656f-6bdfc46416f1@blackwall.org>
Date:   Thu, 21 Apr 2022 13:17:51 +0300
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Subject: Re: [PATCH net-next] net: bridge: switchdev: check br_vlan_group()
 return value
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To:     =?UTF-8?B?Q2zDqW1lbnQgTMOpZ2Vy?= <clement.leger@bootlin.com>,
        Roopa Prabhu <roopa@nvidia.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Tobias Waldekranz <tobias@waldekranz.com>
Cc:     bridge@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20220421101247.121896-1-clement.leger@bootlin.com>
From:   Nikolay Aleksandrov <razor@blackwall.org>
In-Reply-To: <20220421101247.121896-1-clement.leger@bootlin.com>
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On 21/04/2022 13:12, Clément Léger wrote:
> br_vlan_group() can return NULL and thus return value must be checked
> to avoid dereferencing a NULL pointer.
> 
> Fixes: 6284c723d9b9 ("net: bridge: mst: Notify switchdev drivers of VLAN MSTI migrations")
> Signed-off-by: Clément Léger <clement.leger@bootlin.com>
> ---
>  net/bridge/br_switchdev.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
> index 81400e0b26ac..8f3d76c751dd 100644
> --- a/net/bridge/br_switchdev.c
> +++ b/net/bridge/br_switchdev.c
> @@ -354,6 +354,8 @@ static int br_switchdev_vlan_attr_replay(struct net_device *br_dev,
>  	attr.orig_dev = br_dev;
>  
>  	vg = br_vlan_group(br);
> +	if (!vg)
> +		return 0;
>  
>  	list_for_each_entry(v, &vg->vlan_list, vlist) {
>  		if (v->msti) {


Good catch.
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>