ipvs: fix build errors related to config option combinations

Fix two build error introduced by commit 63dca2c0:
"ipvs: Fix faulty IPv6 extension header handling in IPVS"

First build error was fairly trivial and can occur, when CONFIG_IP_VS_IPV6 is disabled.

The second build error was tricky, and can occur when deselecting both all Netfilter and IPVS, but selecting CONFIG_IPV6. This is caused by "kernel/sysctl_binary.c" including "net/ip_vs.h", which includes "linux/netfilter_ipv6/ip6_tables.h" causing include of "include/linux/netfilter/x_tables.h" which then cannot find the typedef nf_hookfn.

Fix this by only including "linux/netfilter_ipv6/ip6_tables.h" in case of CONFIG_IP_VS_IPV6 as its already used to guard the usage of ipv6_find_hdr().

Reported-by Fengguang Wu <[email protected]>

Reported-by Yuanhan Liu <[email protected]>

Signed-off-by Jesper Dangaard Brouer <[email protected]>

---

 include/net/ip_vs.h |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

include/net/ip_vs.h +3 -2

index a681ad6..68c69d5 100644
@@ -22,7 +22,7 @@
 #include <linux/ip.h>
 #include <linux/ipv6.h>			/* for struct ipv6hdr */
 #include <net/ipv6.h>
-#if IS_ENABLED(CONFIG_IPV6)
+#if IS_ENABLED(CONFIG_IP_VS_IPV6)
 #include <linux/netfilter_ipv6/ip6_tables.h>
 #endif
 #if IS_ENABLED(CONFIG_NF_CONNTRACK)

@@ -212,8 +212,9 @@ ip_vs_fill_iph_addr_only(int af, const struct sk_buff *skb,
 			(struct ipv6hdr *)skb_network_header(skb);
 		iphdr->saddr.in6 = iph->saddr;
 		iphdr->daddr.in6 = iph->daddr;
-	} else {
+	} else
 #endif
+	{
 		const struct iphdr *iph =
 			(struct iphdr *)skb_network_header(skb);
 		iphdr->saddr.ip = iph->saddr;

Quoted 13 lines · Jesper Dangaard Brouer

Fix two build error introduced by commit 63dca2c0:
"ipvs: Fix faulty IPv6 extension header handling in IPVS"

First build error was fairly trivial and can occur, when CONFIG_IP_VS_IPV6 is disabled.

The second build error was tricky, and can occur when deselecting both all Netfilter and IPVS, but selecting CONFIG_IPV6. This is caused by "kernel/sysctl_binary.c" including "net/ip_vs.h", which includes "linux/netfilter_ipv6/ip6_tables.h" causing include of "include/linux/netfilter/x_tables.h" which then cannot find the typedef nf_hookfn.

Quoted 3 lines

Fix this by only including "linux/netfilter_ipv6/ip6_tables.h" in case of CONFIG_IP_VS_IPV6 as its already used to guard the usage of ipv6_find_hdr().

Thanks, I have verified both of these fixes and I will send a pull request ASAP.

I do wonder how we might get earlier test coverage of these kinds of problems.

Quoted 14 lines · Simon Horman

Quoted 13 lines · Jesper Dangaard Brouer

Fix two build error introduced by commit 63dca2c0:
"ipvs: Fix faulty IPv6 extension header handling in IPVS"

First build error was fairly trivial and can occur, when CONFIG_IP_VS_IPV6 is disabled.

The second build error was tricky, and can occur when deselecting both all Netfilter and IPVS, but selecting CONFIG_IPV6. This is caused by "kernel/sysctl_binary.c" including "net/ip_vs.h", which includes "linux/netfilter_ipv6/ip6_tables.h" causing include of "include/linux/netfilter/x_tables.h" which then cannot find the typedef nf_hookfn.

Quoted 8 lines

Quoted 3 lines

Fix this by only including "linux/netfilter_ipv6/ip6_tables.h" in case of CONFIG_IP_VS_IPV6 as its already used to guard the usage of ipv6_find_hdr().

Thanks, I have verified both of these fixes and I will send a pull request ASAP.

I do wonder how we might get earlier test coverage of these kinds of problems.

David already mentioned that we (Netfilter/IPVS) should aim to reduce the amount of ifdef pollution in the code. Sometimes it is possible in a nice way by encapsulating code that depends on the feature in one single file.

Sometimes it also requires some more thinking to make it that way (not as easy as adding ifdef).

I think if we aim to that, we can avoid this sort of problems.