1 files changed, 302 insertions, 56 deletions

diff --git a/net/socket.c b/net/socket.c
index 3c176a12fe48..472fbefa5d9b 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -90,6 +90,7 @@
 #include <linux/slab.h>
 #include <linux/xattr.h>
 #include <linux/nospec.h>
+#include <linux/indirect_call_wrapper.h>
 
 #include <linux/uaccess.h>
 #include <asm/unistd.h>
@@ -108,6 +109,13 @@
 #include <net/busy_poll.h>
 #include <linux/errqueue.h>
 
+/* proto_ops for ipv4 and ipv6 use the same {recv,send}msg function */
+#if IS_ENABLED(CONFIG_INET)
+#define INDIRECT_CALL_INET4(f, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__)
+#else
+#define INDIRECT_CALL_INET4(f, f1, ...) f(__VA_ARGS__)
+#endif
+
 #ifdef CONFIG_NET_RX_BUSY_POLL
 unsigned int sysctl_net_busy_read __read_mostly;
 unsigned int sysctl_net_busy_poll __read_mostly;
@@ -384,6 +392,18 @@ static struct file_system_type sock_fs_type = {
  *	but we take care of internal coherence yet.
  */
 
+/**
+ *	sock_alloc_file - Bind a &socket to a &file
+ *	@sock: socket
+ *	@flags: file status flags
+ *	@dname: protocol name
+ *
+ *	Returns the &file bound with @sock, implicitly storing it
+ *	in sock->file. If dname is %NULL, sets to "".
+ *	On failure the return is a ERR pointer (see linux/err.h).
+ *	This function uses GFP_KERNEL internally.
+ */
+
 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
 {
 	struct file *file;
@@ -424,6 +444,14 @@ static int sock_map_fd(struct socket *sock, int flags)
 	return PTR_ERR(newfile);
 }
 
+/**
+ *	sock_from_file - Return the &socket bounded to @file.
+ *	@file: file
+ *	@err: pointer to an error code return
+ *
+ *	On failure returns %NULL and assigns -ENOTSOCK to @err.
+ */
+
 struct socket *sock_from_file(struct file *file, int *err)
 {
 	if (file->f_op == &socket_file_ops)
@@ -532,11 +560,11 @@ static const struct inode_operations sockfs_inode_ops = {
 };
 
 /**
- *	sock_alloc	-	allocate a socket
+ *	sock_alloc - allocate a socket
  *
  *	Allocate a new inode and socket object. The two are bound together
  *	and initialised. The socket is then returned. If we are out of inodes
- *	NULL is returned.
+ *	NULL is returned. This functions uses GFP_KERNEL internally.
  */
 
 struct socket *sock_alloc(void)
@@ -561,7 +589,7 @@ struct socket *sock_alloc(void)
 EXPORT_SYMBOL(sock_alloc);
 
 /**
- *	sock_release	-	close a socket
+ *	sock_release - close a socket
  *	@sock: socket to close
  *
  *	The socket is released from the protocol stack if it has a release
@@ -617,9 +645,20 @@ void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
 }
 EXPORT_SYMBOL(__sock_tx_timestamp);
 
+/**
+ *	sock_sendmsg - send a message through @sock
+ *	@sock: socket
+ *	@msg: message to send
+ *
+ *	Sends @msg through @sock, passing through LSM.
+ *	Returns the number of bytes sent, or an error code.
+ */
+INDIRECT_CALLABLE_DECLARE(int inet_sendmsg(struct socket *, struct msghdr *,
+					   size_t));
 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)
 {
-	int ret = sock->ops->sendmsg(sock, msg, msg_data_left(msg));
+	int ret = INDIRECT_CALL_INET4(sock->ops->sendmsg, inet_sendmsg, sock,
+				      msg, msg_data_left(msg));
 	BUG_ON(ret == -EIOCBQUEUED);
 	return ret;
 }
@@ -633,6 +672,18 @@ int sock_sendmsg(struct socket *sock, struct msghdr *msg)
 }
 EXPORT_SYMBOL(sock_sendmsg);
 
+/**
+ *	kernel_sendmsg - send a message through @sock (kernel-space)
+ *	@sock: socket
+ *	@msg: message header
+ *	@vec: kernel vec
+ *	@num: vec array length
+ *	@size: total message data size
+ *
+ *	Builds the message data with @vec and sends it through @sock.
+ *	Returns the number of bytes sent, or an error code.
+ */
+
 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
 		   struct kvec *vec, size_t num, size_t size)
 {
@@ -641,6 +692,19 @@ int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
 }
 EXPORT_SYMBOL(kernel_sendmsg);
 
+/**
+ *	kernel_sendmsg_locked - send a message through @sock (kernel-space)
+ *	@sk: sock
+ *	@msg: message header
+ *	@vec: output s/g array
+ *	@num: output s/g array length
+ *	@size: total message data size
+ *
+ *	Builds the message data with @vec and sends it through @sock.
+ *	Returns the number of bytes sent, or an error code.
+ *	Caller must hold @sk.
+ */
+
 int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
 			  struct kvec *vec, size_t num, size_t size)
 {
@@ -811,10 +875,22 @@ void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
 }
 EXPORT_SYMBOL_GPL(__sock_recv_ts_and_drops);
 
+/**
+ *	sock_recvmsg - receive a message from @sock
+ *	@sock: socket
+ *	@msg: message to receive
+ *	@flags: message flags
+ *
+ *	Receives @msg from @sock, passing through LSM. Returns the total number
+ *	of bytes received, or an error.
+ */
+INDIRECT_CALLABLE_DECLARE(int inet_recvmsg(struct socket *, struct msghdr *,
+					   size_t , int ));
 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,
 				     int flags)
 {
-	return sock->ops->recvmsg(sock, msg, msg_data_left(msg), flags);
+	return INDIRECT_CALL_INET4(sock->ops->recvmsg, inet_recvmsg, sock, msg,
+				   msg_data_left(msg), flags);
 }
 
 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
@@ -826,20 +902,21 @@ int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)
 EXPORT_SYMBOL(sock_recvmsg);
 
 /**
- * kernel_recvmsg - Receive a message from a socket (kernel space)
- * @sock:       The socket to receive the message from
- * @msg:        Received message
- * @vec:        Input s/g array for message data
- * @num:        Size of input s/g array
- * @size:       Number of bytes to read
- * @flags:      Message flags (MSG_DONTWAIT, etc...)
+ *	kernel_recvmsg - Receive a message from a socket (kernel space)
+ *	@sock: The socket to receive the message from
+ *	@msg: Received message
+ *	@vec: Input s/g array for message data
+ *	@num: Size of input s/g array
+ *	@size: Number of bytes to read
+ *	@flags: Message flags (MSG_DONTWAIT, etc...)
  *
- * On return the msg structure contains the scatter/gather array passed in the
- * vec argument. The array is modified so that it consists of the unfilled
- * portion of the original array.
+ *	On return the msg structure contains the scatter/gather array passed in the
+ *	vec argument. The array is modified so that it consists of the unfilled
+ *	portion of the original array.
  *
- * The returned value is the total number of bytes received, or an error.
+ *	The returned value is the total number of bytes received, or an error.
  */
+
 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
 		   struct kvec *vec, size_t num, size_t size, int flags)
 {
@@ -1005,6 +1082,13 @@ static long sock_do_ioctl(struct net *net, struct socket *sock,
  *	what to do with it - that's up to the protocol still.
  */
 
+/**
+ *	get_net_ns - increment the refcount of the network namespace
+ *	@ns: common namespace (net)
+ *
+ *	Returns the net's common namespace.
+ */
+
 struct ns_common *get_net_ns(struct ns_common *ns)
 {
 	return &get_net(container_of(ns, struct net, ns))->ns;
@@ -1092,6 +1176,26 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 
 			err = open_related_ns(&net->ns, get_net_ns);
 			break;
+		case SIOCGSTAMP_OLD:
+		case SIOCGSTAMPNS_OLD:
+			if (!sock->ops->gettstamp) {
+				err = -ENOIOCTLCMD;
+				break;
+			}
+			err = sock->ops->gettstamp(sock, argp,
+						   cmd == SIOCGSTAMP_OLD,
+						   !IS_ENABLED(CONFIG_64BIT));
+			break;
+		case SIOCGSTAMP_NEW:
+		case SIOCGSTAMPNS_NEW:
+			if (!sock->ops->gettstamp) {
+				err = -ENOIOCTLCMD;
+				break;
+			}
+			err = sock->ops->gettstamp(sock, argp,
+						   cmd == SIOCGSTAMP_NEW,
+						   false);
+			break;
 		default:
 			err = sock_do_ioctl(net, sock, cmd, arg);
 			break;
@@ -1099,6 +1203,19 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 	return err;
 }
 
+/**
+ *	sock_create_lite - creates a socket
+ *	@family: protocol family (AF_INET, ...)
+ *	@type: communication type (SOCK_STREAM, ...)
+ *	@protocol: protocol (0, ...)
+ *	@res: new socket
+ *
+ *	Creates a new socket and assigns it to @res, passing through LSM.
+ *	The new socket initialization is not complete, see kernel_accept().
+ *	Returns 0 or an error. On failure @res is set to %NULL.
+ *	This function internally uses GFP_KERNEL.
+ */
+
 int sock_create_lite(int family, int type, int protocol, struct socket **res)
 {
 	int err;
@@ -1224,6 +1341,21 @@ call_kill:
 }
 EXPORT_SYMBOL(sock_wake_async);
 
+/**
+ *	__sock_create - creates a socket
+ *	@net: net namespace
+ *	@family: protocol family (AF_INET, ...)
+ *	@type: communication type (SOCK_STREAM, ...)
+ *	@protocol: protocol (0, ...)
+ *	@res: new socket
+ *	@kern: boolean for kernel space sockets
+ *
+ *	Creates a new socket and assigns it to @res, passing through LSM.
+ *	Returns 0 or an error. On failure @res is set to %NULL. @kern must
+ *	be set to true if the socket resides in kernel space.
+ *	This function internally uses GFP_KERNEL.
+ */
+
 int __sock_create(struct net *net, int family, int type, int protocol,
 			 struct socket **res, int kern)
 {
@@ -1333,12 +1465,35 @@ out_release:
 }
 EXPORT_SYMBOL(__sock_create);
 
+/**
+ *	sock_create - creates a socket
+ *	@family: protocol family (AF_INET, ...)
+ *	@type: communication type (SOCK_STREAM, ...)
+ *	@protocol: protocol (0, ...)
+ *	@res: new socket
+ *
+ *	A wrapper around __sock_create().
+ *	Returns 0 or an error. This function internally uses GFP_KERNEL.
+ */
+
 int sock_create(int family, int type, int protocol, struct socket **res)
 {
 	return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
 }
 EXPORT_SYMBOL(sock_create);
 
+/**
+ *	sock_create_kern - creates a socket (kernel space)
+ *	@net: net namespace
+ *	@family: protocol family (AF_INET, ...)
+ *	@type: communication type (SOCK_STREAM, ...)
+ *	@protocol: protocol (0, ...)
+ *	@res: new socket
+ *
+ *	A wrapper around __sock_create().
+ *	Returns 0 or an error. This function internally uses GFP_KERNEL.
+ */
+
 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)
 {
 	return __sock_create(net, family, type, protocol, res, 1);
@@ -2793,38 +2948,6 @@ void socket_seq_show(struct seq_file *seq)
 #endif				/* CONFIG_PROC_FS */
 
 #ifdef CONFIG_COMPAT
-static int do_siocgstamp(struct net *net, struct socket *sock,
-			 unsigned int cmd, void __user *up)
-{
-	mm_segment_t old_fs = get_fs();
-	struct timeval ktv;
-	int err;
-
-	set_fs(KERNEL_DS);
-	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&ktv);
-	set_fs(old_fs);
-	if (!err)
-		err = compat_put_timeval(&ktv, up);
-
-	return err;
-}
-
-static int do_siocgstampns(struct net *net, struct socket *sock,
-			   unsigned int cmd, void __user *up)
-{
-	mm_segment_t old_fs = get_fs();
-	struct timespec kts;
-	int err;
-
-	set_fs(KERNEL_DS);
-	err = sock_do_ioctl(net, sock, cmd, (unsigned long)&kts);
-	set_fs(old_fs);
-	if (!err)
-		err = compat_put_timespec(&kts, up);
-
-	return err;
-}
-
 static int compat_dev_ifconf(struct net *net, struct compat_ifconf __user *uifc32)
 {
 	struct compat_ifconf ifc32;
@@ -3224,10 +3347,13 @@ static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
 	case SIOCADDRT:
 	case SIOCDELRT:
 		return routing_ioctl(net, sock, cmd, argp);
-	case SIOCGSTAMP:
-		return do_siocgstamp(net, sock, cmd, argp);
-	case SIOCGSTAMPNS:
-		return do_siocgstampns(net, sock, cmd, argp);
+	case SIOCGSTAMP_OLD:
+	case SIOCGSTAMPNS_OLD:
+		if (!sock->ops->gettstamp)
+			return -ENOIOCTLCMD;
+		return sock->ops->gettstamp(sock, argp, cmd == SIOCGSTAMP_OLD,
+					    !COMPAT_USE_64BIT_TIME);
+
 	case SIOCBONDSLAVEINFOQUERY:
 	case SIOCBONDINFOQUERY:
 	case SIOCSHWTSTAMP:
@@ -3245,6 +3371,8 @@ static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,
 	case SIOCADDDLCI:
 	case SIOCDELDLCI:
 	case SIOCGSKNS:
+	case SIOCGSTAMP_NEW:
+	case SIOCGSTAMPNS_NEW:
 		return sock_ioctl(file, cmd, arg);
 
 	case SIOCGIFFLAGS:
@@ -3322,18 +3450,46 @@ static long compat_sock_ioctl(struct file *file, unsigned int cmd,
 }
 #endif
 
+/**
+ *	kernel_bind - bind an address to a socket (kernel space)
+ *	@sock: socket
+ *	@addr: address
+ *	@addrlen: length of address
+ *
+ *	Returns 0 or an error.
+ */
+
 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
 {
 	return sock->ops->bind(sock, addr, addrlen);
 }
 EXPORT_SYMBOL(kernel_bind);
 
+/**
+ *	kernel_listen - move socket to listening state (kernel space)
+ *	@sock: socket
+ *	@backlog: pending connections queue size
+ *
+ *	Returns 0 or an error.
+ */
+
 int kernel_listen(struct socket *sock, int backlog)
 {
 	return sock->ops->listen(sock, backlog);
 }
 EXPORT_SYMBOL(kernel_listen);
 
+/**
+ *	kernel_accept - accept a connection (kernel space)
+ *	@sock: listening socket
+ *	@newsock: new connected socket
+ *	@flags: flags
+ *
+ *	@flags must be SOCK_CLOEXEC, SOCK_NONBLOCK or 0.
+ *	If it fails, @newsock is guaranteed to be %NULL.
+ *	Returns 0 or an error.
+ */
+
 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
 {
 	struct sock *sk = sock->sk;
@@ -3359,6 +3515,19 @@ done:
 }
 EXPORT_SYMBOL(kernel_accept);
 
+/**
+ *	kernel_connect - connect a socket (kernel space)
+ *	@sock: socket
+ *	@addr: address
+ *	@addrlen: address length
+ *	@flags: flags (O_NONBLOCK, ...)
+ *
+ *	For datagram sockets, @addr is the addres to which datagrams are sent
+ *	by default, and the only address from which datagrams are received.
+ *	For stream sockets, attempts to connect to @addr.
+ *	Returns 0 or an error code.
+ */
+
 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
 		   int flags)
 {
@@ -3366,18 +3535,48 @@ int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
 }
 EXPORT_SYMBOL(kernel_connect);
 
+/**
+ *	kernel_getsockname - get the address which the socket is bound (kernel space)
+ *	@sock: socket
+ *	@addr: address holder
+ *
+ * 	Fills the @addr pointer with the address which the socket is bound.
+ *	Returns 0 or an error code.
+ */
+
 int kernel_getsockname(struct socket *sock, struct sockaddr *addr)
 {
 	return sock->ops->getname(sock, addr, 0);
 }
 EXPORT_SYMBOL(kernel_getsockname);
 
+/**
+ *	kernel_peername - get the address which the socket is connected (kernel space)
+ *	@sock: socket
+ *	@addr: address holder
+ *
+ * 	Fills the @addr pointer with the address which the socket is connected.
+ *	Returns 0 or an error code.
+ */
+
 int kernel_getpeername(struct socket *sock, struct sockaddr *addr)
 {
 	return sock->ops->getname(sock, addr, 1);
 }
 EXPORT_SYMBOL(kernel_getpeername);
 
+/**
+ *	kernel_getsockopt - get a socket option (kernel space)
+ *	@sock: socket
+ *	@level: API level (SOL_SOCKET, ...)
+ *	@optname: option tag
+ *	@optval: option value
+ *	@optlen: option length
+ *
+ *	Assigns the option length to @optlen.
+ *	Returns 0 or an error.
+ */
+
 int kernel_getsockopt(struct socket *sock, int level, int optname,
 			char *optval, int *optlen)
 {
@@ -3400,6 +3599,17 @@ int kernel_getsockopt(struct socket *sock, int level, int optname,
 }
 EXPORT_SYMBOL(kernel_getsockopt);
 
+/**
+ *	kernel_setsockopt - set a socket option (kernel space)
+ *	@sock: socket
+ *	@level: API level (SOL_SOCKET, ...)
+ *	@optname: option tag
+ *	@optval: option value
+ *	@optlen: option length
+ *
+ *	Returns 0 or an error.
+ */
+
 int kernel_setsockopt(struct socket *sock, int level, int optname,
 			char *optval, unsigned int optlen)
 {
@@ -3420,6 +3630,17 @@ int kernel_setsockopt(struct socket *sock, int level, int optname,
 }
 EXPORT_SYMBOL(kernel_setsockopt);
 
+/**
+ *	kernel_sendpage - send a &page through a socket (kernel space)
+ *	@sock: socket
+ *	@page: page
+ *	@offset: page offset
+ *	@size: total size in bytes
+ *	@flags: flags (MSG_DONTWAIT, ...)
+ *
+ *	Returns the total amount sent in bytes or an error.
+ */
+
 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 		    size_t size, int flags)
 {
@@ -3430,6 +3651,18 @@ int kernel_sendpage(struct socket *sock, struct page *page, int offset,
 }
 EXPORT_SYMBOL(kernel_sendpage);
 
+/**
+ *	kernel_sendpage_locked - send a &page through the locked sock (kernel space)
+ *	@sk: sock
+ *	@page: page
+ *	@offset: page offset
+ *	@size: total size in bytes
+ *	@flags: flags (MSG_DONTWAIT, ...)
+ *
+ *	Returns the total amount sent in bytes or an error.
+ *	Caller must hold @sk.
+ */
+
 int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
 			   size_t size, int flags)
 {
@@ -3443,17 +3676,30 @@ int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
 }
 EXPORT_SYMBOL(kernel_sendpage_locked);
 
+/**
+ *	kernel_shutdown - shut down part of a full-duplex connection (kernel space)
+ *	@sock: socket
+ *	@how: connection part
+ *
+ *	Returns 0 or an error.
+ */
+
 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
 {
 	return sock->ops->shutdown(sock, how);
 }
 EXPORT_SYMBOL(kernel_sock_shutdown);
 
-/* This routine returns the IP overhead imposed by a socket i.e.
- * the length of the underlying IP header, depending on whether
- * this is an IPv4 or IPv6 socket and the length from IP options turned
- * on at the socket. Assumes that the caller has a lock on the socket.
+/**
+ *	kernel_sock_ip_overhead - returns the IP overhead imposed by a socket
+ *	@sk: socket
+ *
+ *	This routine returns the IP overhead imposed by a socket i.e.
+ *	the length of the underlying IP header, depending on whether
+ *	this is an IPv4 or IPv6 socket and the length from IP options turned
+ *	on at the socket. Assumes that the caller has a lock on the socket.
  */
+
 u32 kernel_sock_ip_overhead(struct sock *sk)
 {
 	struct inet_sock *inet;