1 files changed, 35 insertions, 12 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 930d17fa906c..6bb9f3cde0b0 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -574,11 +574,6 @@ static int netlink_insert(struct sock *sk, u32 portid)
 	if (nlk_sk(sk)->bound)
 		goto err;
 
-	err = -ENOMEM;
-	if (BITS_PER_LONG > 32 &&
-	    unlikely(atomic_read(&table->hash.nelems) >= UINT_MAX))
-		goto err;
-
 	nlk_sk(sk)->portid = portid;
 	sock_hold(sk);
 
@@ -993,7 +988,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 	struct netlink_sock *nlk = nlk_sk(sk);
 	struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
 	int err = 0;
-	long unsigned int groups = nladdr->nl_groups;
+	unsigned long groups = nladdr->nl_groups;
 	bool bound;
 
 	if (addr_len < sizeof(struct sockaddr_nl))
@@ -1011,9 +1006,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 			return err;
 	}
 
-	if (nlk->ngroups == 0)
-		groups = 0;
-	else if (nlk->ngroups < 8*sizeof(groups))
+	if (nlk->ngroups < BITS_PER_LONG)
 		groups &= (1UL << nlk->ngroups) - 1;
 
 	bound = nlk->bound;
@@ -1713,6 +1706,13 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
 			nlk->flags &= ~NETLINK_F_EXT_ACK;
 		err = 0;
 		break;
+	case NETLINK_DUMP_STRICT_CHK:
+		if (val)
+			nlk->flags |= NETLINK_F_STRICT_CHK;
+		else
+			nlk->flags &= ~NETLINK_F_STRICT_CHK;
+		err = 0;
+		break;
 	default:
 		err = -ENOPROTOOPT;
 	}
@@ -1806,6 +1806,15 @@ static int netlink_getsockopt(struct socket *sock, int level, int optname,
 			return -EFAULT;
 		err = 0;
 		break;
+	case NETLINK_DUMP_STRICT_CHK:
+		if (len < sizeof(int))
+			return -EINVAL;
+		len = sizeof(int);
+		val = nlk->flags & NETLINK_F_STRICT_CHK ? 1 : 0;
+		if (put_user(len, optlen) || put_user(val, optval))
+			return -EFAULT;
+		err = 0;
+		break;
 	default:
 		err = -ENOPROTOOPT;
 	}
@@ -2178,6 +2187,7 @@ EXPORT_SYMBOL(__nlmsg_put);
 static int netlink_dump(struct sock *sk)
 {
 	struct netlink_sock *nlk = nlk_sk(sk);
+	struct netlink_ext_ack extack = {};
 	struct netlink_callback *cb;
 	struct sk_buff *skb = NULL;
 	struct nlmsghdr *nlh;
@@ -2229,8 +2239,11 @@ static int netlink_dump(struct sock *sk)
 	skb_reserve(skb, skb_tailroom(skb) - alloc_size);
 	netlink_skb_set_owner_r(skb, sk);
 
-	if (nlk->dump_done_errno > 0)
+	if (nlk->dump_done_errno > 0) {
+		cb->extack = &extack;
 		nlk->dump_done_errno = cb->dump(skb, cb);
+		cb->extack = NULL;
+	}
 
 	if (nlk->dump_done_errno > 0 ||
 	    skb_tailroom(skb) < nlmsg_total_size(sizeof(nlk->dump_done_errno))) {
@@ -2244,7 +2257,8 @@ static int netlink_dump(struct sock *sk)
 	}
 
 	nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE,
-			       sizeof(nlk->dump_done_errno), NLM_F_MULTI);
+			       sizeof(nlk->dump_done_errno),
+			       NLM_F_MULTI | cb->answer_flags);
 	if (WARN_ON(!nlh))
 		goto errout_skb;
 
@@ -2253,6 +2267,12 @@ static int netlink_dump(struct sock *sk)
 	memcpy(nlmsg_data(nlh), &nlk->dump_done_errno,
 	       sizeof(nlk->dump_done_errno));
 
+	if (extack._msg && nlk->flags & NETLINK_F_EXT_ACK) {
+		nlh->nlmsg_flags |= NLM_F_ACK_TLVS;
+		if (!nla_put_string(skb, NLMSGERR_ATTR_MSG, extack._msg))
+			nlmsg_end(skb, nlh);
+	}
+
 	if (sk_filter(sk, skb))
 		kfree_skb(skb);
 	else
@@ -2279,9 +2299,9 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 			 const struct nlmsghdr *nlh,
 			 struct netlink_dump_control *control)
 {
+	struct netlink_sock *nlk, *nlk2;
 	struct netlink_callback *cb;
 	struct sock *sk;
-	struct netlink_sock *nlk;
 	int ret;
 
 	refcount_inc(&skb->users);
@@ -2315,6 +2335,9 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 	cb->min_dump_alloc = control->min_dump_alloc;
 	cb->skb = skb;
 
+	nlk2 = nlk_sk(NETLINK_CB(skb).sk);
+	cb->strict_check = !!(nlk2->flags & NETLINK_F_STRICT_CHK);
+
 	if (control->start) {
 		ret = control->start(cb);
 		if (ret)