netdev - Re: net/smc and the RDMA core

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]

Date:   Thu, 4 May 2017 15:08:39 +0200
From:   Ursula Braun <ubraun@...ux.vnet.ibm.com>
To:     "hch@....de" <hch@....de>, Sagi Grimberg <sagi@...mberg.me>
Cc:     Bart Van Assche <Bart.VanAssche@...disk.com>,
        "davem@...emloft.net" <davem@...emloft.net>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-rdma@...r.kernel.org" <linux-rdma@...r.kernel.org>
Subject: Re: net/smc and the RDMA core



On 05/04/2017 10:48 AM, hch@....de wrote:
> On Thu, May 04, 2017 at 11:43:50AM +0300, Sagi Grimberg wrote:
>> I would also suggest that you stop exposing the DMA MR for remote
>> access (at least by default) and use a proper reg_mr operations with a
>> limited lifetime on a properly sized buffer.
> 
> Yes, exposing the default DMA MR is a _major_ security risk.  As soon
> as SMC is enabled this will mean a remote system has full read/write
> access to the local systems memory.
> 
> There іs a reason why I removed the ib_get_dma_mr function and replaced
> it with the IB_PD_UNSAFE_GLOBAL_RKEY key that has _UNSAFE_ in the name
> and a very long comment explaining why, and I'm really disappointed that
> we got a driver merged that instead of asking on the relevant list on
> why a change unexpertong a function it needed happened and instead
> tried the hard way to keep a security vulnerarbility alive.
> 
Thanks for pointing out these problems. We will address them.