netdev - Re: [PATCH net] netlink: fix netlink

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: <20131109.000012.1393414533296613338.davem@davemloft.net>
Date:	Sat, 09 Nov 2013 00:00:12 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	tgraf@...g.ch
Cc:	jbenc@...hat.com, netdev@...r.kernel.org, pablo@...filter.org
Subject: Re: [PATCH net] netlink: fix netlink_ack with large messages

From: Thomas Graf <tgraf@...g.ch>
Date: Sat, 9 Nov 2013 00:04:34 +0000

> I agree it seems over the top for pure ACKs but we also use
> netlink_ack() to report errors where it makes sense to quote
> the full message.

The user has the message, they gave it to us in the sendmsg()
we are responding to.  We absolutely do not need to give it
to them again.

If they care about referring to the contents of that message, they can
refer to it in their own copy and make sure they are really looking at
the same thing by comparing the sequence number in the netlink ACK to
the one they used in the netlink header they gave to the kernel in the
sendmsg() call.

What happens now is pure duplication, and for such huge netlink
messages it's really not smart at all.

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html