netdev - Re: [PATCH] cipso: don't use IPCB() to locate the CIPSO IP option

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 06 Feb 2015 15:03:05 -0500
From:	Paul Moore <pmoore@...hat.com>
To:	davem@...emloft.net
Cc:	linux-security-module@...r.kernel.org, selinux@...ho.nsa.gov,
	casey@...aufler-ca.com, netdev@...r.kernel.org
Subject: Re: [PATCH] cipso: don't use IPCB() to locate the CIPSO IP option

On Friday, February 06, 2015 02:57:28 PM Paul Moore wrote:
> Using the IPCB() macro to get the IPv4 options is convenient, but
> unfortunately NetLabel often needs to examine the CIPSO option outside
> of the scope of the IP layer in the stack.  While historically IPCB()
> worked above the IP layer, due to the inclusion of the inet_skb_param
> struct at the head of the {tcp,udp}_skb_cb structs, recent commit
> 971f10ec ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
> reordered the tcp_skb_cb struct and invalidated this IPCB() trick.
> 
> This patch fixes the problem by creating a new function,
> cipso_v4_optptr(), which locates the CIPSO option inside the IP header
> without calling IPCB().  Unfortunately, this isn't as fast as a simple
> lookup so some additional tweaks were made to limit the use of this
> new function.
> 
> Cc: <stable@...r.kernel.org> # 3.18
> Reported-by: Casey Schaufler <casey@...aufler-ca.com>
> Signed-off-by: Paul Moore <pmoore@...hat.com>

DaveM, I'd prefer this go upstream via the SELinux/security tree so we don't 
have to worry about syncing up with the netdev tree to get this fix.  Any 
objections on your part (this patch only touches NetLabel/CIPSO)?

-- 
paul moore
security @ redhat

--
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