1 files changed, 30 insertions, 25 deletions

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 653136d68b32..f2f234f0b92c 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -758,8 +758,6 @@ static int unix_compat_ioctl(struct socket *sock, unsigned int cmd, unsigned lon
 static int unix_shutdown(struct socket *, int);
 static int unix_stream_sendmsg(struct socket *, struct msghdr *, size_t);
 static int unix_stream_recvmsg(struct socket *, struct msghdr *, size_t, int);
-static ssize_t unix_stream_sendpage(struct socket *, struct page *, int offset,
-				    size_t size, int flags);
 static ssize_t unix_stream_splice_read(struct socket *,  loff_t *ppos,
 				       struct pipe_inode_info *, size_t size,
 				       unsigned int flags);
@@ -852,7 +850,6 @@ static const struct proto_ops unix_stream_ops = {
 	.recvmsg =	unix_stream_recvmsg,
 	.read_skb =	unix_stream_read_skb,
 	.mmap =		sock_no_mmap,
-	.sendpage =	unix_stream_sendpage,
 	.splice_read =	unix_stream_splice_read,
 	.set_peek_off =	unix_set_peek_off,
 	.show_fdinfo =	unix_show_fdinfo,
@@ -878,7 +875,6 @@ static const struct proto_ops unix_dgram_ops = {
 	.read_skb =	unix_read_skb,
 	.recvmsg =	unix_dgram_recvmsg,
 	.mmap =		sock_no_mmap,
-	.sendpage =	sock_no_sendpage,
 	.set_peek_off =	unix_set_peek_off,
 	.show_fdinfo =	unix_show_fdinfo,
 };
@@ -902,7 +898,6 @@ static const struct proto_ops unix_seqpacket_ops = {
 	.sendmsg =	unix_seqpacket_sendmsg,
 	.recvmsg =	unix_seqpacket_recvmsg,
 	.mmap =		sock_no_mmap,
-	.sendpage =	sock_no_sendpage,
 	.set_peek_off =	unix_set_peek_off,
 	.show_fdinfo =	unix_show_fdinfo,
 };
@@ -921,11 +916,26 @@ static void unix_unhash(struct sock *sk)
 	 */
 }
 
+static bool unix_bpf_bypass_getsockopt(int level, int optname)
+{
+	if (level == SOL_SOCKET) {
+		switch (optname) {
+		case SO_PEERPIDFD:
+			return true;
+		default:
+			return false;
+		}
+	}
+
+	return false;
+}
+
 struct proto unix_dgram_proto = {
 	.name			= "UNIX",
 	.owner			= THIS_MODULE,
 	.obj_size		= sizeof(struct unix_sock),
 	.close			= unix_close,
+	.bpf_bypass_getsockopt	= unix_bpf_bypass_getsockopt,
 #ifdef CONFIG_BPF_SYSCALL
 	.psock_update_sk_prot	= unix_dgram_bpf_update_proto,
 #endif
@@ -937,6 +947,7 @@ struct proto unix_stream_proto = {
 	.obj_size		= sizeof(struct unix_sock),
 	.close			= unix_close,
 	.unhash			= unix_unhash,
+	.bpf_bypass_getsockopt	= unix_bpf_bypass_getsockopt,
 #ifdef CONFIG_BPF_SYSCALL
 	.psock_update_sk_prot	= unix_stream_bpf_update_proto,
 #endif
@@ -1361,7 +1372,8 @@ static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
 		if (err)
 			goto out;
 
-		if (test_bit(SOCK_PASSCRED, &sock->flags) &&
+		if ((test_bit(SOCK_PASSCRED, &sock->flags) ||
+		     test_bit(SOCK_PASSPIDFD, &sock->flags)) &&
 		    !unix_sk(sk)->addr) {
 			err = unix_autobind(sk);
 			if (err)
@@ -1469,7 +1481,8 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 	if (err)
 		goto out;
 
-	if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr) {
+	if ((test_bit(SOCK_PASSCRED, &sock->flags) ||
+	     test_bit(SOCK_PASSPIDFD, &sock->flags)) && !u->addr) {
 		err = unix_autobind(sk);
 		if (err)
 			goto out;
@@ -1670,6 +1683,8 @@ static void unix_sock_inherit_flags(const struct socket *old,
 {
 	if (test_bit(SOCK_PASSCRED, &old->flags))
 		set_bit(SOCK_PASSCRED, &new->flags);
+	if (test_bit(SOCK_PASSPIDFD, &old->flags))
+		set_bit(SOCK_PASSPIDFD, &new->flags);
 	if (test_bit(SOCK_PASSSEC, &old->flags))
 		set_bit(SOCK_PASSSEC, &new->flags);
 }
@@ -1819,8 +1834,10 @@ static bool unix_passcred_enabled(const struct socket *sock,
 				  const struct sock *other)
 {
 	return test_bit(SOCK_PASSCRED, &sock->flags) ||
+	       test_bit(SOCK_PASSPIDFD, &sock->flags) ||
 	       !other->sk_socket ||
-	       test_bit(SOCK_PASSCRED, &other->sk_socket->flags);
+	       test_bit(SOCK_PASSCRED, &other->sk_socket->flags) ||
+	       test_bit(SOCK_PASSPIDFD, &other->sk_socket->flags);
 }
 
 /*
@@ -1904,7 +1921,8 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
 			goto out;
 	}
 
-	if (test_bit(SOCK_PASSCRED, &sock->flags) && !u->addr) {
+	if ((test_bit(SOCK_PASSCRED, &sock->flags) ||
+	     test_bit(SOCK_PASSPIDFD, &sock->flags)) && !u->addr) {
 		err = unix_autobind(sk);
 		if (err)
 			goto out;
@@ -2271,20 +2289,6 @@ out_err:
 	return sent ? : err;
 }
 
-static ssize_t unix_stream_sendpage(struct socket *socket, struct page *page,
-				    int offset, size_t size, int flags)
-{
-	struct bio_vec bvec;
-	struct msghdr msg = { .msg_flags = flags | MSG_SPLICE_PAGES };
-
-	if (flags & MSG_SENDPAGE_NOTLAST)
-		msg.msg_flags |= MSG_MORE;
-
-	bvec_set_page(&bvec, page, size, offset);
-	iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size);
-	return unix_stream_sendmsg(socket, &msg, size);
-}
-
 static int unix_seqpacket_sendmsg(struct socket *sock, struct msghdr *msg,
 				  size_t len)
 {
@@ -2718,7 +2722,8 @@ unlock:
 			/* Never glue messages from different writers */
 			if (!unix_skb_scm_eq(skb, &scm))
 				break;
-		} else if (test_bit(SOCK_PASSCRED, &sock->flags)) {
+		} else if (test_bit(SOCK_PASSCRED, &sock->flags) ||
+			   test_bit(SOCK_PASSPIDFD, &sock->flags)) {
 			/* Copy credentials */
 			scm_set_cred(&scm, UNIXCB(skb).pid, UNIXCB(skb).uid, UNIXCB(skb).gid);
 			unix_set_secdata(&scm, skb);
@@ -2802,7 +2807,7 @@ unlock:
 	} while (size);
 
 	mutex_unlock(&u->iolock);
-	if (state->msg)
+	if (state->msg && check_creds)
 		scm_recv(sock, state->msg, &scm, flags);
 	else
 		scm_destroy(&scm);