2011-03-30 02:13:22

by Steven Rostedt

[permalink] [raw]
Subject: [PATCH] netfilter: Fix build failure when ipv6 but xt_tproxy is built in

While running ktest.pl doing ranconfigs, the following build error
occurred:

net/built-in.o: In function `tproxy_tg6_v1':
/home/rostedt/work/autotest/nobackup/linux-test.git/net/netfilter/xt_TPROXY.c:288: undefined reference to `ipv6_find_hdr'

This happened because the xt_TPROXY code was compiled into the kernel
proper, but the ipv6 netfilter was compiled as a module. The fix is to
only enter the code that calls ipv6_find_hdr if ipv6 netfilter is
compiled into the kernel, or if it is a module, so is the xt_TPROXY
code.

Signed-off-by: Steven Rostedt <[email protected]>

diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
index dcfd57e..5915f94 100644
--- a/net/netfilter/xt_TPROXY.c
+++ b/net/netfilter/xt_TPROXY.c
@@ -22,7 +22,13 @@

#include <net/netfilter/ipv4/nf_defrag_ipv4.h>

-#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
+/*
+ * Only include the following if ip6 tables is compiled in
+ * the kernel, or it is a module and this code is also a module.
+ */
+#if defined(CONFIG_IP6_NF_IPTABLES) || \
+ (defined(CONFIG_IP6_NF_IPTABLES_MODULE) && \
+ defined(CONFIG_NETFILTER_XT_TARGET_TPROXY_MODULE))
#define XT_TPROXY_HAVE_IPV6 1
#include <net/if_inet6.h>
#include <net/addrconf.h>


2011-03-30 05:36:15

by David Miller

[permalink] [raw]
Subject: Re: [PATCH] netfilter: Fix build failure when ipv6 but xt_tproxy is built in

From: Steven Rostedt <[email protected]>
Date: Tue, 29 Mar 2011 22:13:19 -0400

> While running ktest.pl doing ranconfigs, the following build error
> occurred:

Is sending netfilter patches to the explicitly listed maintainer in
MAINTAINERS too much to ask Stephen? :-/

CC:'d

>
> net/built-in.o: In function `tproxy_tg6_v1':
> /home/rostedt/work/autotest/nobackup/linux-test.git/net/netfilter/xt_TPROXY.c:288: undefined reference to `ipv6_find_hdr'
>
> This happened because the xt_TPROXY code was compiled into the kernel
> proper, but the ipv6 netfilter was compiled as a module. The fix is to
> only enter the code that calls ipv6_find_hdr if ipv6 netfilter is
> compiled into the kernel, or if it is a module, so is the xt_TPROXY
> code.
>
> Signed-off-by: Steven Rostedt <[email protected]>
>
> diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
> index dcfd57e..5915f94 100644
> --- a/net/netfilter/xt_TPROXY.c
> +++ b/net/netfilter/xt_TPROXY.c
> @@ -22,7 +22,13 @@
>
> #include <net/netfilter/ipv4/nf_defrag_ipv4.h>
>
> -#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
> +/*
> + * Only include the following if ip6 tables is compiled in
> + * the kernel, or it is a module and this code is also a module.
> + */
> +#if defined(CONFIG_IP6_NF_IPTABLES) || \
> + (defined(CONFIG_IP6_NF_IPTABLES_MODULE) && \
> + defined(CONFIG_NETFILTER_XT_TARGET_TPROXY_MODULE))
> #define XT_TPROXY_HAVE_IPV6 1
> #include <net/if_inet6.h>
> #include <net/addrconf.h>
>
>

2011-03-30 10:18:25

by Steven Rostedt

[permalink] [raw]
Subject: Re: [PATCH] netfilter: Fix build failure when ipv6 but xt_tproxy is built in

On Tue, 2011-03-29 at 22:35 -0700, David Miller wrote:
> From: Steven Rostedt <[email protected]>
> Date: Tue, 29 Mar 2011 22:13:19 -0400
>
> > While running ktest.pl doing ranconfigs, the following build error
> > occurred:
>
> Is sending netfilter patches to the explicitly listed maintainer in
> MAINTAINERS too much to ask Stephen? :-/
>
> CC:'d
>

Sorry David, I just did a git blame and Cc'd the ones that did the
original change. I'll do better next time.

-- Steve

2011-04-04 13:54:48

by Patrick McHardy

[permalink] [raw]
Subject: Re: [PATCH] netfilter: Fix build failure when ipv6 but xt_tproxy is built in

On 30.03.2011 07:35, David Miller wrote:
> From: Steven Rostedt <[email protected]>
> Date: Tue, 29 Mar 2011 22:13:19 -0400
>
>> While running ktest.pl doing ranconfigs, the following build error
>> occurred:
>
> Is sending netfilter patches to the explicitly listed maintainer in
> MAINTAINERS too much to ask Stephen? :-/
>
> CC:'d
>
>>
>> net/built-in.o: In function `tproxy_tg6_v1':
>> /home/rostedt/work/autotest/nobackup/linux-test.git/net/netfilter/xt_TPROXY.c:288: undefined reference to `ipv6_find_hdr'
>>
>> This happened because the xt_TPROXY code was compiled into the kernel
>> proper, but the ipv6 netfilter was compiled as a module. The fix is to
>> only enter the code that calls ipv6_find_hdr if ipv6 netfilter is
>> compiled into the kernel, or if it is a module, so is the xt_TPROXY
>> code.

I don't think this is a good fix for the problem since it may lead to
the confusing situation that both TPROXY and ip6tables are enabled,
but TPROXY has no IPv6 support.

I think we should solve this by either adding a Kconfig dependency
on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n) or using ipv6_skip_exthdr()
instead of ipv6_find_hdr().

Krisztian, what do you think?

>>
>> Signed-off-by: Steven Rostedt <[email protected]>
>>
>> diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
>> index dcfd57e..5915f94 100644
>> --- a/net/netfilter/xt_TPROXY.c
>> +++ b/net/netfilter/xt_TPROXY.c
>> @@ -22,7 +22,13 @@
>>
>> #include <net/netfilter/ipv4/nf_defrag_ipv4.h>
>>
>> -#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
>> +/*
>> + * Only include the following if ip6 tables is compiled in
>> + * the kernel, or it is a module and this code is also a module.
>> + */
>> +#if defined(CONFIG_IP6_NF_IPTABLES) || \
>> + (defined(CONFIG_IP6_NF_IPTABLES_MODULE) && \
>> + defined(CONFIG_NETFILTER_XT_TARGET_TPROXY_MODULE))
>> #define XT_TPROXY_HAVE_IPV6 1
>> #include <net/if_inet6.h>
>> #include <net/addrconf.h>
>>
>>
>

2011-04-05 14:43:50

by KOVACS Krisztian

[permalink] [raw]
Subject: Re: [PATCH] netfilter: Fix build failure when ipv6 but xt_tproxy is built in

Hi,

On Mon, 2011-04-04 at 15:54 +0200, Patrick McHardy wrote:
> >> net/built-in.o: In function `tproxy_tg6_v1':
> >> /home/rostedt/work/autotest/nobackup/linux-test.git/net/netfilter/xt_TPROXY.c:288: undefined reference to `ipv6_find_hdr'
> >>
> >> This happened because the xt_TPROXY code was compiled into the kernel
> >> proper, but the ipv6 netfilter was compiled as a module. The fix is to
> >> only enter the code that calls ipv6_find_hdr if ipv6 netfilter is
> >> compiled into the kernel, or if it is a module, so is the xt_TPROXY
> >> code.
>
> I don't think this is a good fix for the problem since it may lead to
> the confusing situation that both TPROXY and ip6tables are enabled,
> but TPROXY has no IPv6 support.
>
> I think we should solve this by either adding a Kconfig dependency
> on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n) or using ipv6_skip_exthdr()
> instead of ipv6_find_hdr().
>
> Krisztian, what do you think?

I'd definitely prefer using ipv6_skip_exthdr() instead of playing
various tricks with the config preprocessor macros.

What about something like this?

diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
index dcfd57e..1ef0e56 100644
--- a/net/netfilter/xt_TPROXY.c
+++ b/net/netfilter/xt_TPROXY.c
@@ -283,10 +283,10 @@ tproxy_tg6_v1(struct sk_buff *skb, const struct xt_action_param *par)
const struct in6_addr *laddr;
__be16 lport;
int thoff;
- int tproto;
+ u8 tproto = iph->nexthdr;

- tproto = ipv6_find_hdr(skb, &thoff, -1, NULL);
- if (tproto < 0) {
+ thoff = ipv6_skip_exthdr(skb, sizeof(*iph), &tproto);
+ if (thoff < 0) {
pr_debug("unable to find transport header in IPv6 packet, dropping\n");
return NF_DROP;
}

--
KOVACS Krisztian

2011-04-05 14:49:29

by Patrick McHardy

[permalink] [raw]
Subject: Re: [PATCH] netfilter: Fix build failure when ipv6 but xt_tproxy is built in

Am 05.04.2011 16:43, schrieb KOVACS Krisztian:
> Hi,
>
> On Mon, 2011-04-04 at 15:54 +0200, Patrick McHardy wrote:
>>>> net/built-in.o: In function `tproxy_tg6_v1':
>>>> /home/rostedt/work/autotest/nobackup/linux-test.git/net/netfilter/xt_TPROXY.c:288: undefined reference to `ipv6_find_hdr'
>>>>
>>>> This happened because the xt_TPROXY code was compiled into the kernel
>>>> proper, but the ipv6 netfilter was compiled as a module. The fix is to
>>>> only enter the code that calls ipv6_find_hdr if ipv6 netfilter is
>>>> compiled into the kernel, or if it is a module, so is the xt_TPROXY
>>>> code.
>>
>> I don't think this is a good fix for the problem since it may lead to
>> the confusing situation that both TPROXY and ip6tables are enabled,
>> but TPROXY has no IPv6 support.
>>
>> I think we should solve this by either adding a Kconfig dependency
>> on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n) or using ipv6_skip_exthdr()
>> instead of ipv6_find_hdr().
>>
>> Krisztian, what do you think?
>
> I'd definitely prefer using ipv6_skip_exthdr() instead of playing
> various tricks with the config preprocessor macros.
>
> What about something like this?
>
> diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
> index dcfd57e..1ef0e56 100644
> --- a/net/netfilter/xt_TPROXY.c
> +++ b/net/netfilter/xt_TPROXY.c
> @@ -283,10 +283,10 @@ tproxy_tg6_v1(struct sk_buff *skb, const struct xt_action_param *par)
> const struct in6_addr *laddr;
> __be16 lport;
> int thoff;
> - int tproto;
> + u8 tproto = iph->nexthdr;
>
> - tproto = ipv6_find_hdr(skb, &thoff, -1, NULL);
> - if (tproto < 0) {
> + thoff = ipv6_skip_exthdr(skb, sizeof(*iph), &tproto);
> + if (thoff < 0) {
> pr_debug("unable to find transport header in IPv6 packet, dropping\n");
> return NF_DROP;
> }

Looks good to me. Please formally submit this including a Signed-off-by:
line and I'll push it upstream.

2011-04-06 12:08:54

by KOVACS Krisztian

[permalink] [raw]
Subject: Re: [PATCH] netfilter: Fix build failure when ipv6 but xt_tproxy is built in

Hi,

On 04/05/2011 04:49 PM, Patrick McHardy wrote:
>> What about something like this?
>>
>> diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
>> index dcfd57e..1ef0e56 100644
>> --- a/net/netfilter/xt_TPROXY.c
>> +++ b/net/netfilter/xt_TPROXY.c
>> @@ -283,10 +283,10 @@ tproxy_tg6_v1(struct sk_buff *skb, const struct xt_action_param *par)
>> const struct in6_addr *laddr;
>> __be16 lport;
>> int thoff;
>> - int tproto;
>> + u8 tproto = iph->nexthdr;
>>
>> - tproto = ipv6_find_hdr(skb, &thoff, -1, NULL);
>> - if (tproto < 0) {
>> + thoff = ipv6_skip_exthdr(skb, sizeof(*iph), &tproto);
>> + if (thoff < 0) {
>> pr_debug("unable to find transport header in IPv6 packet, dropping\n");
>> return NF_DROP;
>> }
>
> Looks good to me. Please formally submit this including a Signed-off-by:
> line and I'll push it upstream.

Will do, as soon as I have a chance to run the test suite. Thanks Patrick.

--
KOVACS Krisztian