netdev - Re: [ovs-dev] [PATCH] openvswitch: call only into reachable nf-nat code

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, 17 Mar 2016 16:09:18 +1300
From:	Joe Stringer <joe@....org>
To:	Arnd Bergmann <arnd@...db.de>
Cc:	Pablo Neira Ayuso <pablo@...filter.org>,
	Pravin Shelar <pshelar@...ira.com>,
	"David S. Miller" <davem@...emloft.net>,
	ovs dev <dev@...nvswitch.org>, netdev <netdev@...r.kernel.org>,
	linux-kernel@...r.kernel.org,
	Joe Stringer <joestringer@...ira.com>,
	Paolo Abeni <pabeni@...hat.com>
Subject: Re: [ovs-dev] [PATCH] openvswitch: call only into reachable nf-nat code

On 17 March 2016 at 01:47, Arnd Bergmann <arnd@...db.de> wrote:
> The openvswitch code has gained support for calling into the
> nf-nat-ipv4/ipv6 modules, however those can be loadable modules
> in a configuration in which openvswitch is built-in, leading
> to link errors:
>
> net/built-in.o: In function `__ovs_ct_lookup':
> :(.text+0x2cc2c8): undefined reference to `nf_nat_icmp_reply_translation'
> :(.text+0x2cc66c): undefined reference to `nf_nat_icmpv6_reply_translation'
>
> The dependency on (!NF_NAT || NF_NAT) was meant to prevent
> this, but NF_NAT is set to 'y' if any of the symbols selecting
> it are built-in, but the link error happens when any of them
> are modular.
>
> A second issue is that even if CONFIG_NF_NAT_IPV6 is built-in,
> CONFIG_NF_NAT_IPV4 might be completely disabled. This is unlikely
> to be useful in practice, but the driver currently only handles
> IPv6 being optional.
>
> This patch improves the Kconfig dependency so that openvswitch
> cannot be built-in if either of the two other symbols are set
> to 'm', and it replaces the incorrect #ifdef in ovs_ct_nat_execute()
> with two "if (IS_ENABLED())" checks that should catch all corner
> cases also make the code more readable.
>
> The same #ifdef exists ovs_ct_nat_to_attr(), where it does not
> cause a link error, but for consistency I'm changing it the same
> way.
>
> Signed-off-by: Arnd Bergmann <arnd@...db.de>
> Fixes: 05752523e565 ("openvswitch: Interface with NAT.")

Thanks for the fix, LGTM.

Acked-by: Joe Stringer <joe@....org>