3 files changed, 35 insertions, 16 deletions

diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index f0540c557515..9d690d32da33 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -69,12 +69,15 @@ DEFINE_COOKIE(net_cookie);
 
 static struct net_generic *net_alloc_generic(void)
 {
+	unsigned int gen_ptrs = READ_ONCE(max_gen_ptrs);
+	unsigned int generic_size;
 	struct net_generic *ng;
-	unsigned int generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
+
+	generic_size = offsetof(struct net_generic, ptr[gen_ptrs]);
 
 	ng = kzalloc(generic_size, GFP_KERNEL);
 	if (ng)
-		ng->s.len = max_gen_ptrs;
+		ng->s.len = gen_ptrs;
 
 	return ng;
 }
@@ -1307,7 +1310,11 @@ static int register_pernet_operations(struct list_head *list,
 		if (error < 0)
 			return error;
 		*ops->id = error;
-		max_gen_ptrs = max(max_gen_ptrs, *ops->id + 1);
+		/* This does not require READ_ONCE as writers already hold
+		 * pernet_ops_rwsem. But WRITE_ONCE is needed to protect
+		 * net_alloc_generic.
+		 */
+		WRITE_ONCE(max_gen_ptrs, max(max_gen_ptrs, *ops->id + 1));
 	}
 	error = __register_pernet_operations(list, ops);
 	if (error) {
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index a3d7847ce69d..8ba6a4e4be26 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2530,7 +2530,7 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr **tb)
 
 		nla_for_each_nested(attr, tb[IFLA_VF_VLAN_LIST], rem) {
 			if (nla_type(attr) != IFLA_VF_VLAN_INFO ||
-			    nla_len(attr) < NLA_HDRLEN) {
+			    nla_len(attr) < sizeof(struct ifla_vf_vlan_info)) {
 				return -EINVAL;
 			}
 			if (len >= MAX_VLAN_LIST_LEN)
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 4096e679f61c..1169fdbdb2c3 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1708,7 +1708,7 @@ static struct ubuf_info *msg_zerocopy_alloc(struct sock *sk, size_t size)
 		return NULL;
 	}
 
-	uarg->ubuf.callback = msg_zerocopy_callback;
+	uarg->ubuf.ops = &msg_zerocopy_ubuf_ops;
 	uarg->id = ((u32)atomic_inc_return(&sk->sk_zckey)) - 1;
 	uarg->len = 1;
 	uarg->bytelen = size;
@@ -1734,7 +1734,7 @@ struct ubuf_info *msg_zerocopy_realloc(struct sock *sk, size_t size,
 		u32 bytelen, next;
 
 		/* there might be non MSG_ZEROCOPY users */
-		if (uarg->callback != msg_zerocopy_callback)
+		if (uarg->ops != &msg_zerocopy_ubuf_ops)
 			return NULL;
 
 		/* realloc only when socket is locked (TCP, UDP cork),
@@ -1845,8 +1845,8 @@ release:
 	sock_put(sk);
 }
 
-void msg_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *uarg,
-			   bool success)
+static void msg_zerocopy_complete(struct sk_buff *skb, struct ubuf_info *uarg,
+				  bool success)
 {
 	struct ubuf_info_msgzc *uarg_zc = uarg_to_msgzc(uarg);
 
@@ -1855,7 +1855,6 @@ void msg_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *uarg,
 	if (refcount_dec_and_test(&uarg->refcnt))
 		__msg_zerocopy_callback(uarg_zc);
 }
-EXPORT_SYMBOL_GPL(msg_zerocopy_callback);
 
 void msg_zerocopy_put_abort(struct ubuf_info *uarg, bool have_uref)
 {
@@ -1865,10 +1864,15 @@ void msg_zerocopy_put_abort(struct ubuf_info *uarg, bool have_uref)
 	uarg_to_msgzc(uarg)->len--;
 
 	if (have_uref)
-		msg_zerocopy_callback(NULL, uarg, true);
+		msg_zerocopy_complete(NULL, uarg, true);
 }
 EXPORT_SYMBOL_GPL(msg_zerocopy_put_abort);
 
+const struct ubuf_info_ops msg_zerocopy_ubuf_ops = {
+	.complete = msg_zerocopy_complete,
+};
+EXPORT_SYMBOL_GPL(msg_zerocopy_ubuf_ops);
+
 int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb,
 			     struct msghdr *msg, int len,
 			     struct ubuf_info *uarg)
@@ -1876,11 +1880,18 @@ int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb,
 	struct ubuf_info *orig_uarg = skb_zcopy(skb);
 	int err, orig_len = skb->len;
 
-	/* An skb can only point to one uarg. This edge case happens when
-	 * TCP appends to an skb, but zerocopy_realloc triggered a new alloc.
-	 */
-	if (orig_uarg && uarg != orig_uarg)
-		return -EEXIST;
+	if (uarg->ops->link_skb) {
+		err = uarg->ops->link_skb(skb, uarg);
+		if (err)
+			return err;
+	} else {
+		/* An skb can only point to one uarg. This edge case happens
+		 * when TCP appends to an skb, but zerocopy_realloc triggered
+		 * a new alloc.
+		 */
+		if (orig_uarg && uarg != orig_uarg)
+			return -EEXIST;
+	}
 
 	err = __zerocopy_sg_from_iter(msg, sk, skb, &msg->msg_iter, len);
 	if (err == -EFAULT || (err == -EMSGSIZE && skb->len == orig_len)) {
@@ -1894,7 +1905,8 @@ int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb,
 		return err;
 	}
 
-	skb_zcopy_set(skb, uarg, NULL);
+	if (!uarg->ops->link_skb)
+		skb_zcopy_set(skb, uarg, NULL);
 	return skb->len - orig_len;
 }
 EXPORT_SYMBOL_GPL(skb_zerocopy_iter_stream);