netfilter: avoid ipv6 -> nf_defrag_ipv6 module dependency

[ Upstream commit 2404b73c3f1a5f15726c6ecd226b56f6f992767f ]

nf_ct_frag6_gather is part of nf_defrag_ipv6.ko, not ipv6 core.

The current use of the netfilter ipv6 stub indirections  causes a module
dependency between ipv6 and nf_defrag_ipv6.

This prevents nf_defrag_ipv6 module from being removed because ipv6 can't
be unloaded.

Remove the indirection and always use a direct call.  This creates a
depency from nf_conntrack_bridge to nf_defrag_ipv6 instead:

modinfo nf_conntrack
depends:        nf_conntrack,nf_defrag_ipv6,bridge

.. and nf_conntrack already depends on nf_defrag_ipv6 anyway.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/include/linux/netfilter_ipv6.h b/include/linux/netfilter_ipv6.h
index aac42c28fe62d746c710370fa63c2c9aef2feae9..9b67394471e1c63462327d5cefdd7ab2701e0acf 100644 (file)
--- a/include/linux/netfilter_ipv6.h
+++ b/include/linux/netfilter_ipv6.h
@@ -58,7 +58,6 @@ struct nf_ipv6_ops {
                        int (*output)(struct net *, struct sock *, struct sk_buff *));
        int (*reroute)(struct sk_buff *skb, const struct nf_queue_entry *entry);
 #if IS_MODULE(CONFIG_IPV6)
-       int (*br_defrag)(struct net *net, struct sk_buff *skb, u32 user);
        int (*br_fragment)(struct net *net, struct sock *sk,
                           struct sk_buff *skb,
                           struct nf_bridge_frag_data *data,
@@ -117,23 +116,6 @@ static inline int nf_ip6_route(struct net *net, struct dst_entry **dst,
 
 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
 
-static inline int nf_ipv6_br_defrag(struct net *net, struct sk_buff *skb,
-                                   u32 user)
-{
-#if IS_MODULE(CONFIG_IPV6)
-       const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
-
-       if (!v6_ops)
-               return 1;
-
-       return v6_ops->br_defrag(net, skb, user);
-#elif IS_BUILTIN(CONFIG_IPV6)
-       return nf_ct_frag6_gather(net, skb, user);
-#else
-       return 1;
-#endif
-}
-
 int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
                    struct nf_bridge_frag_data *data,
                    int (*output)(struct net *, struct sock *sk,

diff --git a/net/bridge/netfilter/nf_conntrack_bridge.c b/net/bridge/netfilter/nf_conntrack_bridge.c
index 8096732223828a7110ab35d715fe1894ddf57a91..8d033a75a766ef529e201bc04060c2b14e7709cb 100644 (file)
--- a/net/bridge/netfilter/nf_conntrack_bridge.c
+++ b/net/bridge/netfilter/nf_conntrack_bridge.c
@@ -168,6 +168,7 @@ static unsigned int nf_ct_br_defrag4(struct sk_buff *skb,
 static unsigned int nf_ct_br_defrag6(struct sk_buff *skb,
                                     const struct nf_hook_state *state)
 {
+#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
        u16 zone_id = NF_CT_DEFAULT_ZONE_ID;
        enum ip_conntrack_info ctinfo;
        struct br_input_skb_cb cb;
@@ -180,14 +181,17 @@ static unsigned int nf_ct_br_defrag6(struct sk_buff *skb,
 
        br_skb_cb_save(skb, &cb, sizeof(struct inet6_skb_parm));
 
-       err = nf_ipv6_br_defrag(state->net, skb,
-                               IP_DEFRAG_CONNTRACK_BRIDGE_IN + zone_id);
+       err = nf_ct_frag6_gather(state->net, skb,
+                                IP_DEFRAG_CONNTRACK_BRIDGE_IN + zone_id);
        /* queued */
        if (err == -EINPROGRESS)
                return NF_STOLEN;
 
        br_skb_cb_restore(skb, &cb, IP6CB(skb)->frag_max_size);
        return err == 0 ? NF_ACCEPT : NF_DROP;
+#else
+       return NF_ACCEPT;
+#endif
 }
 
 static int nf_ct_br_ip_check(const struct sk_buff *skb)

diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c
index 409e79b84a830dd22ffe7728f45d9dc65ec01df4..6d0e942d082d4ec0f66cb97fb20a7c466a0a0dfa 100644 (file)
--- a/net/ipv6/netfilter.c
+++ b/net/ipv6/netfilter.c
@@ -245,9 +245,6 @@ static const struct nf_ipv6_ops ipv6ops = {
        .route_input            = ip6_route_input,
        .fragment               = ip6_fragment,
        .reroute                = nf_ip6_reroute,
-#if IS_MODULE(CONFIG_IPV6) && IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
-       .br_defrag              = nf_ct_frag6_gather,
-#endif
 #if IS_MODULE(CONFIG_IPV6)
        .br_fragment            = br_ip6_fragment,
 #endif