netns xfrm: add struct xfrm_policy::xp_net

Again, to avoid complications with passing netns when not necessary.
Again, ->xp_net is set-once field, once set it never changes.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 16 insertions, 7 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 0d4353c11093..1ab17565f01c 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -475,6 +475,9 @@ struct xfrm_policy_walk {
 
 struct xfrm_policy
 {
+#ifdef CONFIG_NET_NS
+        struct net              *xp_net;
+#endif
         struct hlist_node       bydst;
         struct hlist_node       byidx;
 
@@ -499,6 +502,11 @@ struct xfrm_policy
         struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 };
 
+static inline struct net *xp_net(struct xfrm_policy *xp)
+{
+        return read_pnet(&xp->xp_net);
+}
+
 struct xfrm_kmaddress {
         xfrm_address_t          local;
         xfrm_address_t          remote;
@@ -1425,7 +1433,7 @@ static inline int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
 }
 #endif
 
-struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp);
+struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp);
 
 extern void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type);
 extern int xfrm_policy_walk(struct xfrm_policy_walk *walk,
diff --git a/net/key/af_key.c b/net/key/af_key.c
index f202ba6c8dcb..036315d6b665 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -2174,7 +2174,7 @@ static int pfkey_spdadd(struct sock *sk, struct sk_buff *skb, struct sadb_msg *h
         if (!pol->sadb_x_policy_dir || pol->sadb_x_policy_dir >= IPSEC_DIR_MAX)
                 return -EINVAL;
 
-        xp = xfrm_policy_alloc(GFP_KERNEL);
+        xp = xfrm_policy_alloc(&init_net, GFP_KERNEL);
         if (xp == NULL)
                 return -ENOBUFS;
 
@@ -3141,7 +3141,7 @@ static struct xfrm_policy *pfkey_compile_policy(struct sock *sk, int opt,
             (!pol->sadb_x_policy_dir || pol->sadb_x_policy_dir > IPSEC_DIR_OUTBOUND))
                 return NULL;
 
-        xp = xfrm_policy_alloc(GFP_ATOMIC);
+        xp = xfrm_policy_alloc(&init_net, GFP_ATOMIC);
         if (xp == NULL) {
                 *dir = -ENOBUFS;
                 return NULL;
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index cf2bf3aa7ab4..3eccefae2c8a 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -228,13 +228,14 @@ expired:
  * SPD calls.
  */
 
-struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp)
+struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 {
         struct xfrm_policy *policy;
 
         policy = kzalloc(sizeof(struct xfrm_policy), gfp);
 
         if (policy) {
+                write_pnet(&policy->xp_net, net);
                 INIT_LIST_HEAD(&policy->walk.all);
                 INIT_HLIST_NODE(&policy->bydst);
                 INIT_HLIST_NODE(&policy->byidx);
@@ -1153,7 +1154,7 @@ int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
 
 static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
 {
-        struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC);
+        struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
 
         if (newp) {
                 newp->selector = old->selector;
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 65cdaa5c2280..765c01e784e9 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1080,7 +1080,7 @@ static void copy_to_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_i
 
 static struct xfrm_policy *xfrm_policy_construct(struct xfrm_userpolicy_info *p, struct nlattr **attrs, int *errp)
 {
-        struct xfrm_policy *xp = xfrm_policy_alloc(GFP_KERNEL);
+        struct xfrm_policy *xp = xfrm_policy_alloc(&init_net, GFP_KERNEL);
         int err;
 
         if (!xp) {
@@ -2291,7 +2291,7 @@ static struct xfrm_policy *xfrm_compile_policy(struct sock *sk, int opt,
         if (p->dir > XFRM_POLICY_OUT)
                 return NULL;
 
-        xp = xfrm_policy_alloc(GFP_KERNEL);
+        xp = xfrm_policy_alloc(&init_net, GFP_KERNEL);
         if (xp == NULL) {
                 *dir = -ENOBUFS;
                 return NULL;