netdev - Re: [PATCH] netfilter: nf_conntrack_bridge: Fix not free when error

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20210728161849.GA10433@salvia>
Date:   Wed, 28 Jul 2021 18:18:49 +0200
From:   Pablo Neira Ayuso <pablo@...filter.org>
To:     Yajun Deng <yajun.deng@...ux.dev>
Cc:     kadlec@...filter.org, fw@...len.de, roopa@...dia.com,
        nikolay@...dia.com, davem@...emloft.net, kuba@...nel.org,
        netfilter-devel@...r.kernel.org, coreteam@...filter.org,
        bridge@...ts.linux-foundation.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] netfilter: nf_conntrack_bridge: Fix not free when error

On Mon, Jul 26, 2021 at 11:57:02AM +0800, Yajun Deng wrote:
> It should be added kfree_skb_list() when err is not equal to zero
> in nf_br_ip_fragment().
> 
> Fixes: 3c171f496ef5 ("netfilter: bridge: add connection tracking system")
> Signed-off-by: Yajun Deng <yajun.deng@...ux.dev>
> ---
>  net/bridge/netfilter/nf_conntrack_bridge.c | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
> 
> diff --git a/net/bridge/netfilter/nf_conntrack_bridge.c b/net/bridge/netfilter/nf_conntrack_bridge.c
> index 8d033a75a766..059f53903eda 100644
> --- a/net/bridge/netfilter/nf_conntrack_bridge.c
> +++ b/net/bridge/netfilter/nf_conntrack_bridge.c
> @@ -83,12 +83,16 @@ static int nf_br_ip_fragment(struct net *net, struct sock *sk,
>  
>  			skb->tstamp = tstamp;
>  			err = output(net, sk, data, skb);
> -			if (err || !iter.frag)
> -				break;
> -
> +			if (err) {
> +				kfree_skb_list(iter.frag);
> +				return err;
> +			}
> +
> +			if (!iter.frag)
> +				return 0;
> +
>  			skb = ip_fraglist_next(&iter);
>  		}
> -		return err;

Why removing this line above? It enters slow_path: on success.

This patch instead will keep this aligned with IPv6.

>  	}
>  slow_path:
>  	/* This is a linearized skbuff, the original geometry is lost for us.
> -- 
> 2.32.0
> 

View attachment "x.patch" of type "text/x-diff" (461 bytes)