From: Al Viro <viro@ZenIV.linux.org.uk>
To: David Miller <davem@davemloft.net>
Cc: kaber@trash.net, netdev@vger.kernel.org
Subject: Re: [WTF?] random test in netlink_sendmsg()
Date: Sat, 13 Dec 2014 01:54:15 +0000 [thread overview]
Message-ID: <20141213015415.GG22149@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20141212.200758.944592759380344519.davem@davemloft.net>
On Fri, Dec 12, 2014 at 08:07:58PM -0500, David Miller wrote:
> From: Al Viro <viro@ZenIV.linux.org.uk>
> Date: Fri, 12 Dec 2014 21:32:43 +0000
>
> > What do we want sendmsg(fd, &msg, 0) to do when fd is AF_NETLINK socket
> > that had setsockopt(fd, SOL_NETLINK, NETLINK_TX_RING, ...) successfully done
> > to it and msg.msg_iovlen is 0?
>
> We had a similar issue with msg_name/msg_namelen and we ended up saying
> that if msg_namelen is zero then we force msg_name to NULL.
Hmm... The thing is, there might be legitimate users with empty payload,
making this call for the sake of SCM_CREDENTIALS. IOW, what should happen
if we have
msg_iovlen = 0
msg_iov = <anything>
msg_control = &cmsg
msg_controllen = cmsg_len
Sure, both paths will pass creds, but what about the payload? And the number
of datagram actually transmitted, for that matter?
next prev parent reply other threads:[~2014-12-13 1:54 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-28 6:23 [WTF?] random test in netlink_sendmsg() Al Viro
2014-12-12 20:34 ` David Miller
2014-12-12 21:32 ` Al Viro
2014-12-12 21:50 ` Florian Westphal
2014-12-12 22:14 ` Al Viro
2014-12-12 22:20 ` Florian Westphal
2014-12-13 1:07 ` David Miller
2014-12-13 1:54 ` Al Viro [this message]
2014-12-13 2:33 ` David Miller
2014-12-13 3:25 ` Al Viro
2014-12-13 4:51 ` Al Viro
2014-12-14 4:38 ` David Miller
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