From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Florian Westphal <fw@strlen.de>
Cc: Phil Sutter <phil@nwl.cc>, netfilter-devel@vger.kernel.org
Subject: Re: [nft PATCH RFC] monitor: Support printing processes which caused the event
Date: Wed, 10 May 2017 13:38:55 +0200 [thread overview]
Message-ID: <20170510113855.GD29824@salvia> (raw)
In-Reply-To: <20170510112724.GD16263@breakpoint.cc>
On Wed, May 10, 2017 at 01:27:24PM +0200, Florian Westphal wrote:
> nlmsg_pid is the netlink portid.
Right.
> While most programs set it to their process id there is no guarantee.
> Its just a (unique) 32 bit identifier.
It's actually the kernel that decides what portID the socket gets
IIRC. For the first socket it uses the process ID, then for follow up
sockets, it just looks for a spare ID in the negative range of the 32
bit, if my memory serves well.
> Afaics one has to use /proc/net/netlink to map the portid to the inode
> and then walk /proc/*/fd/* to find the socket with that inode.
>
> Perhaps there is a simpler way, maybe you can check what ss is doing
> and what info can be obtained via netlink diag.
I wouldn't be surprise if we need more kernel infrastructure to deal
with this. Parsing /proc for a netlink thing is definitely not ideal.
next prev parent reply other threads:[~2017-05-10 11:39 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-05-10 10:55 [nft PATCH RFC] monitor: Support printing processes which caused the event Phil Sutter
2017-05-10 11:27 ` Florian Westphal
2017-05-10 11:38 ` Pablo Neira Ayuso [this message]
2017-05-10 11:57 ` Florian Westphal
2017-05-10 14:39 ` Phil Sutter
2017-05-10 14:54 ` Florian Westphal
2017-05-10 15:11 ` Phil Sutter
2017-05-10 17:59 ` Florian Westphal
2017-05-11 6:41 ` Pablo Neira Ayuso
2017-05-11 6:59 ` Florian Westphal
2017-05-11 8:27 ` Phil Sutter
2017-05-11 9:58 ` Pablo Neira Ayuso
2017-05-11 9:59 ` Pablo Neira Ayuso
2017-05-10 11:34 ` Pablo Neira Ayuso
2017-05-10 12:52 ` Arturo Borrero Gonzalez
2017-05-10 14:02 ` Phil Sutter
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