Return-path: Received: from out1-smtp.messagingengine.com ([66.111.4.25]:59571 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750830AbdGDHom (ORCPT ); Tue, 4 Jul 2017 03:44:42 -0400 Date: Tue, 4 Jul 2017 09:44:42 +0200 From: Greg KH To: Dison River Cc: samuel@sortiz.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, qca_merez@qca.qualcomm.com, kvalo@codeaurora.org, linux-wireless@vger.kernel.org, jakub.kicinski@netronome.com, davem@davemloft.net, oss-drivers@netronome.com, security@kernel.org, wil6210@qca.qualcomm.com Subject: Re: 'skb' buffer address information leakage Message-ID: <20170704074442.GA21877@kroah.com> (sfid-20170704_094549_397111_9FC2D5DB) References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Jul 04, 2017 at 01:12:18PM +0800, Dison River wrote: > Hi all: > I'd found several address leaks of "skb" buffer.When i have a > arbitrary address write vulnerability in kernel(enabled kASLR),I can > use skb's address find sk_destruct's address and overwrite it. And > then,invoke close(sock_fd) function can trigger the > shellcode(sk_destruct func). > > In kernel 4.12-rc7 > drivers/net/irda/vlsi_ir.c:326 seq_printf(seq, "skb=%p > data=%p hw=%p\n", rd->skb, rd->buf, rd->hw); Irda doesn't even work, and will crash, so it's a bit hard to see this as a "leakage" :) I'm going to be ripping irda out soon anyway, so this isn't a real issue. > drivers/net/ethernet/netronome/nfp/nfp_net_debugfs.c:167 > seq_printf(file, " frag=%p", skb); > drivers/net/wireless/ath/wil6210/debugfs.c:926 seq_printf(s, > " SKB = 0x%p\n", skb); debugfs is by nature, root-only access, so the potential for issues here is lower than "any user can get this info". That being said, patches for these are always appreciated. I also need to respin my "turn %p pointers off" patchset to prevent future stuff like this from happening. I want to get to that after 4.13-rc1 is out. thanks, greg k-h