From: Nicolas Dichtel <nicolas.dichtel@6wind•com>
To: Eric Dumazet <eric.dumazet@gmail•com>
Cc: netdev@vger•kernel.org, xiyou.wangcong@gmail•com, davem@davemloft•net
Subject: Re: [PATCH net-next v2 3/5] sock_diag: allow to dump bpf filters
Date: Thu, 25 Apr 2013 10:37:00 +0200 [thread overview]
Message-ID: <5178EB2C.6070709@6wind.com> (raw)
In-Reply-To: <1366820565.8964.78.camel@edumazet-glaptop>
Le 24/04/2013 18:22, Eric Dumazet a écrit :
> On Wed, 2013-04-24 at 17:52 +0200, Nicolas Dichtel wrote:
>> This patch allows to dump BPF filters attached to a socket with
>> SO_ATTACH_FILTER. In other words, users allowing to open netlink sockets can
>> see filters set on a socket (when the diag module of the socket family is
>> loaded).
>
> To my knowledge, opening netlink sockets is not restricted.
>
> I do not want user lambda being able to see my BPF filters.
>
> I am root, and was assuming user lambda could not spy on me.
>
> $ cat /proc/net/packet
> sk RefCnt Type Proto Iface R Rmem User Inode
> 0000000000000000 3 10 0003 3 1 0 0 1089989
> 0000000000000000 3 10 0003 2 1 0 0 1050535
> 0000000000000000 3 2 888e 3 1 0 0 1041970
>
>
> With this information, it seems safe enough, but the whole BPF could
> give interesting ideas to user lambda.
I agree. But then you just have to avoid loading the module packet_diag. This
module already give some clue to users, because it sends the socket pointer
through netlink.
Maybe I'm wrong, but I was thinking that this module is used for debug purpose.
If the module is not loaded, my patch has no effect on the system.
next prev parent reply other threads:[~2013-04-25 8:37 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-23 14:27 [PATCH net-next 0/5] sock_diag: monitor packet sockets Nicolas Dichtel
2013-04-23 14:27 ` [PATCH net-next 1/5] packet_diag: disclose uid value Nicolas Dichtel
2013-04-23 14:27 ` [PATCH net-next 2/5] packet_diag: disclose meminfo values Nicolas Dichtel
2013-04-23 14:27 ` [PATCH net-next 3/5] sock_diag: allow to dump bpf filters Nicolas Dichtel
2013-04-23 15:31 ` Eric Dumazet
2013-04-23 14:27 ` [PATCH net-next 4/5] sock_diag: notify packet socket creation/deletion Nicolas Dichtel
2013-04-23 14:27 ` [PATCH net-next 5/5] sock_diag: notify when filter change Nicolas Dichtel
2013-04-24 8:05 ` Cong Wang
2013-04-24 8:13 ` Nicolas Dichtel
2013-04-24 15:52 ` [PATCH net-next v2 0/5] sock_diag: monitor packet sockets Nicolas Dichtel
2013-04-24 15:52 ` [PATCH net-next v2 1/5] packet_diag: disclose uid value Nicolas Dichtel
2013-04-24 15:52 ` [PATCH net-next v2 2/5] packet_diag: disclose meminfo values Nicolas Dichtel
2013-04-24 15:52 ` [PATCH net-next v2 3/5] sock_diag: allow to dump bpf filters Nicolas Dichtel
2013-04-24 16:22 ` Eric Dumazet
2013-04-25 5:16 ` David Miller
2013-04-25 8:37 ` Nicolas Dichtel [this message]
2013-04-25 9:00 ` David Miller
2013-04-25 13:21 ` [PATCH net-next v3 0/4] sock_diag: monitor packet sockets Nicolas Dichtel
2013-04-25 13:21 ` [PATCH net-next v3 1/4] packet_diag: disclose uid value Nicolas Dichtel
2013-04-25 13:21 ` [PATCH net-next v3 2/4] packet_diag: disclose meminfo values Nicolas Dichtel
2013-04-25 13:21 ` [PATCH net-next v3 3/4] sock_diag: do not disclose sock ptr to all users Nicolas Dichtel
2013-04-25 15:32 ` Eric Dumazet
2013-04-25 15:36 ` Eric Dumazet
2013-04-25 16:45 ` Nicolas Dichtel
2013-04-25 16:57 ` Eric Dumazet
2013-04-25 16:53 ` [PATCH net-next v4 0/3] packet_diag: enhance advertised infos Nicolas Dichtel
2013-04-25 16:53 ` [PATCH net-next v4 1/3] packet_diag: disclose uid value Nicolas Dichtel
2013-04-25 16:53 ` [PATCH net-next v4 2/3] packet_diag: disclose meminfo values Nicolas Dichtel
2013-04-25 16:53 ` [PATCH net-next v4 3/3] sock_diag: allow to dump bpf filters Nicolas Dichtel
2013-04-29 17:22 ` [PATCH net-next v4 0/3] packet_diag: enhance advertised infos David Miller
2013-04-25 13:21 ` [PATCH net-next v3 4/4] sock_diag: allow to dump bpf filters Nicolas Dichtel
2013-04-25 13:51 ` [PATCH net-next v2 3/5] " Eric Dumazet
2013-04-24 15:52 ` [PATCH net-next v2 4/5] sock_diag: notify packet socket creation/deletion Nicolas Dichtel
2013-05-17 14:25 ` [PATCH net-next v3] " Nicolas Dichtel
2013-05-20 6:29 ` David Miller
2013-05-21 15:14 ` Nicolas Dichtel
2013-05-21 18:43 ` David Miller
2013-05-22 11:49 ` Nicolas Dichtel
2013-04-24 15:52 ` [PATCH net-next v2 5/5] sock_diag: notify when filter change Nicolas Dichtel
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