1 files changed, 159 insertions, 69 deletions

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 9c85cdb..f1cc058 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -73,7 +73,7 @@ enum {
 	Opt_cto, Opt_nocto,
 	Opt_ac, Opt_noac,
 	Opt_lock, Opt_nolock,
-	Opt_v2, Opt_v3,
+	Opt_v2, Opt_v3, Opt_v4,
 	Opt_udp, Opt_tcp, Opt_rdma,
 	Opt_acl, Opt_noacl,
 	Opt_rdirplus, Opt_nordirplus,
@@ -127,6 +127,7 @@ static const match_table_t nfs_mount_option_tokens = {
 	{ Opt_nolock, "nolock" },
 	{ Opt_v2, "v2" },
 	{ Opt_v3, "v3" },
+	{ Opt_v4, "v4" },
 	{ Opt_udp, "udp" },
 	{ Opt_tcp, "tcp" },
 	{ Opt_rdma, "rdma" },
@@ -272,6 +273,10 @@ static const struct super_operations nfs_sops = {
 };
 
 #ifdef CONFIG_NFS_V4
+static int nfs4_validate_text_mount_data(void *options,
+	struct nfs_parsed_mount_data *args, const char *dev_name);
+static int nfs4_try_mount(int flags, const char *dev_name,
+	struct nfs_parsed_mount_data *data, struct vfsmount *mnt);
 static int nfs4_get_sb(struct file_system_type *fs_type,
 	int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
@@ -747,6 +752,21 @@ static int nfs_verify_server_address(struct sockaddr *addr)
 }
 
 /*
+ * Select between a default port value and a user-specified port value.
+ * If a zero value is set, then autobind will be used.
+ */
+static void nfs_set_default_port(struct sockaddr *sap, const int parsed_port,
+				 const unsigned short default_port)
+{
+	unsigned short port = default_port;
+
+	if (parsed_port != NFS_UNSPEC_PORT)
+		port = parsed_port;
+
+	rpc_set_port(sap, port);
+}
+
+/*
  * Sanity check the NFS transport protocol.
  *
  */
@@ -915,10 +935,18 @@ static int nfs_parse_mount_options(char *raw,
 			break;
 		case Opt_v2:
 			mnt->flags &= ~NFS_MOUNT_VER3;
+			mnt->version = 2;
 			break;
 		case Opt_v3:
 			mnt->flags |= NFS_MOUNT_VER3;
+			mnt->version = 3;
 			break;
+#ifdef CONFIG_NFS_V4
+		case Opt_v4:
+			mnt->flags &= ~NFS_MOUNT_VER3;
+			mnt->version = 4;
+			break;
+#endif
 		case Opt_udp:
 			mnt->flags &= ~NFS_MOUNT_TCP;
 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
@@ -1132,10 +1160,18 @@ static int nfs_parse_mount_options(char *raw,
 			switch (option) {
 			case NFS2_VERSION:
 				mnt->flags &= ~NFS_MOUNT_VER3;
+				mnt->version = 2;
 				break;
 			case NFS3_VERSION:
 				mnt->flags |= NFS_MOUNT_VER3;
+				mnt->version = 3;
+				break;
+#ifdef CONFIG_NFS_V4
+			case NFS4_VERSION:
+				mnt->flags &= ~NFS_MOUNT_VER3;
+				mnt->version = 4;
 				break;
+#endif
 			default:
 				goto out_invalid_value;
 			}
@@ -1338,6 +1374,16 @@ static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
 	unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
 
 	/*
+	 * Certain releases of Linux's mountd return an empty
+	 * flavor list.  To prevent behavioral regression with
+	 * these servers (ie. rejecting mounts that used to
+	 * succeed), revert to pre-2.6.32 behavior (no checking)
+	 * if the returned flavor list is empty.
+	 */
+	if (server_authlist_len == 0)
+		return 0;
+
+	/*
 	 * We avoid sophisticated negotiating here, as there are
 	 * plenty of cases where we can get it wrong, providing
 	 * either too little or too much security.
@@ -1405,11 +1451,7 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
 		args->mount_server.addrlen = args->nfs_server.addrlen;
 	}
 	request.salen = args->mount_server.addrlen;
-
-	/*
-	 * autobind will be used if mount_server.port == 0
-	 */
-	rpc_set_port(request.sap, args->mount_server.port);
+	nfs_set_default_port(request.sap, args->mount_server.port, 0);
 
 	/*
 	 * Now ask the mount server to map our export path
@@ -1587,6 +1629,7 @@ static int nfs_validate_mount_data(void *options,
 				   const char *dev_name)
 {
 	struct nfs_mount_data *data = (struct nfs_mount_data *)options;
+	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
 
 	if (data == NULL)
 		goto out_no_data;
@@ -1598,11 +1641,12 @@ static int nfs_validate_mount_data(void *options,
 	args->acregmax		= NFS_DEF_ACREGMAX;
 	args->acdirmin		= NFS_DEF_ACDIRMIN;
 	args->acdirmax		= NFS_DEF_ACDIRMAX;
-	args->mount_server.port	= 0;	/* autobind unless user sets port */
-	args->nfs_server.port	= 0;	/* autobind unless user sets port */
+	args->mount_server.port	= NFS_UNSPEC_PORT;
+	args->nfs_server.port	= NFS_UNSPEC_PORT;
 	args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 	args->auth_flavors[0]	= RPC_AUTH_UNIX;
 	args->auth_flavor_len	= 1;
+	args->minorversion	= 0;
 
 	switch (data->version) {
 	case 1:
@@ -1624,8 +1668,11 @@ static int nfs_validate_mount_data(void *options,
 			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
 				goto out_invalid_fh;
 			mntfh->size = data->root.size;
-		} else
+			args->version = 3;
+		} else {
 			mntfh->size = NFS2_FHSIZE;
+			args->version = 2;
+		}
 
 
 		memcpy(mntfh->data, data->root.data, mntfh->size);
@@ -1647,11 +1694,9 @@ static int nfs_validate_mount_data(void *options,
 		args->acdirmin		= data->acdirmin;
 		args->acdirmax		= data->acdirmax;
 
-		memcpy(&args->nfs_server.address, &data->addr,
-		       sizeof(data->addr));
+		memcpy(sap, &data->addr, sizeof(data->addr));
 		args->nfs_server.addrlen = sizeof(data->addr);
-		if (!nfs_verify_server_address((struct sockaddr *)
-						&args->nfs_server.address))
+		if (!nfs_verify_server_address(sap))
 			goto out_no_address;
 
 		if (!(data->flags & NFS_MOUNT_TCP))
@@ -1699,12 +1744,18 @@ static int nfs_validate_mount_data(void *options,
 		if (nfs_parse_mount_options((char *)options, args) == 0)
 			return -EINVAL;
 
-		if (!nfs_verify_server_address((struct sockaddr *)
-						&args->nfs_server.address))
+		if (!nfs_verify_server_address(sap))
 			goto out_no_address;
 
-		rpc_set_port((struct sockaddr *)&args->nfs_server.address,
-				args->nfs_server.port);
+		if (args->version == 4)
+#ifdef CONFIG_NFS_V4
+			return nfs4_validate_text_mount_data(options,
+							     args, dev_name);
+#else
+			goto out_v4_not_compiled;
+#endif
+
+		nfs_set_default_port(sap, args->nfs_server.port, 0);
 
 		nfs_set_mount_transport_protocol(args);
 
@@ -1752,6 +1803,12 @@ out_v3_not_compiled:
 	return -EPROTONOSUPPORT;
 #endif /* !CONFIG_NFS_V3 */
 
+#ifndef CONFIG_NFS_V4
+out_v4_not_compiled:
+	dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
+	return -EPROTONOSUPPORT;
+#endif /* !CONFIG_NFS_V4 */
+
 out_nomem:
 	dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
 	return -ENOMEM;
@@ -1861,6 +1918,8 @@ static inline void nfs_initialise_sb(struct super_block *sb)
 	if (server->flags & NFS_MOUNT_NOAC)
 		sb->s_flags |= MS_SYNCHRONOUS;
 
+	sb->s_bdi = &server->backing_dev_info;
+
 	nfs_super_set_maxbytes(sb, server->maxfilesize);
 }
 
@@ -2047,6 +2106,14 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 	if (error < 0)
 		goto out;
 
+#ifdef CONFIG_NFS_V4
+	if (data->version == 4) {
+		error = nfs4_try_mount(flags, dev_name, data, mnt);
+		kfree(data->client_address);
+		goto out;
+	}
+#endif	/* CONFIG_NFS_V4 */
+
 	/* Get a volume representation */
 	server = nfs_create_server(data, mntfh);
 	if (IS_ERR(server)) {
@@ -2123,8 +2190,8 @@ static void nfs_kill_super(struct super_block *s)
 {
 	struct nfs_server *server = NFS_SB(s);
 
-	bdi_unregister(&server->backing_dev_info);
 	kill_anon_super(s);
+	bdi_unregister(&server->backing_dev_info);
 	nfs_fscache_release_super_cookie(s);
 	nfs_free_server(server);
 }
@@ -2244,6 +2311,43 @@ static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
 	args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3);
 }
 
+static int nfs4_validate_text_mount_data(void *options,
+					 struct nfs_parsed_mount_data *args,
+					 const char *dev_name)
+{
+	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
+
+	nfs_set_default_port(sap, args->nfs_server.port, NFS_PORT);
+
+	nfs_validate_transport_protocol(args);
+
+	nfs4_validate_mount_flags(args);
+
+	if (args->version != 4) {
+		dfprintk(MOUNT,
+			 "NFS4: Illegal mount version\n");
+		return -EINVAL;
+	}
+
+	if (args->auth_flavor_len > 1) {
+		dfprintk(MOUNT,
+			 "NFS4: Too many RPC auth flavours specified\n");
+		return -EINVAL;
+	}
+
+	if (args->client_address == NULL) {
+		dfprintk(MOUNT,
+			 "NFS4: mount program didn't pass callback address\n");
+		return -EINVAL;
+	}
+
+	return nfs_parse_devname(dev_name,
+				   &args->nfs_server.hostname,
+				   NFS4_MAXNAMLEN,
+				   &args->nfs_server.export_path,
+				   NFS4_MAXPATHLEN);
+}
+
 /*
  * Validate NFSv4 mount options
  */
@@ -2251,7 +2355,7 @@ static int nfs4_validate_mount_data(void *options,
 				    struct nfs_parsed_mount_data *args,
 				    const char *dev_name)
 {
-	struct sockaddr_in *ap;
+	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
 	struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
 	char *c;
 
@@ -2264,23 +2368,22 @@ static int nfs4_validate_mount_data(void *options,
 	args->acregmax		= NFS_DEF_ACREGMAX;
 	args->acdirmin		= NFS_DEF_ACDIRMIN;
 	args->acdirmax		= NFS_DEF_ACDIRMAX;
-	args->nfs_server.port	= NFS_PORT; /* 2049 unless user set port= */
+	args->nfs_server.port	= NFS_UNSPEC_PORT;
 	args->auth_flavors[0]	= RPC_AUTH_UNIX;
 	args->auth_flavor_len	= 1;
+	args->version		= 4;
 	args->minorversion	= 0;
 
 	switch (data->version) {
 	case 1:
-		ap = (struct sockaddr_in *)&args->nfs_server.address;
 		if (data->host_addrlen > sizeof(args->nfs_server.address))
 			goto out_no_address;
 		if (data->host_addrlen == 0)
 			goto out_no_address;
 		args->nfs_server.addrlen = data->host_addrlen;
-		if (copy_from_user(ap, data->host_addr, data->host_addrlen))
+		if (copy_from_user(sap, data->host_addr, data->host_addrlen))
 			return -EFAULT;
-		if (!nfs_verify_server_address((struct sockaddr *)
-						&args->nfs_server.address))
+		if (!nfs_verify_server_address(sap))
 			goto out_no_address;
 
 		if (data->auth_flavourlen) {
@@ -2326,39 +2429,14 @@ static int nfs4_validate_mount_data(void *options,
 		nfs_validate_transport_protocol(args);
 
 		break;
-	default: {
-		int status;
-
+	default:
 		if (nfs_parse_mount_options((char *)options, args) == 0)
 			return -EINVAL;
 
-		if (!nfs_verify_server_address((struct sockaddr *)
-						&args->nfs_server.address))
+		if (!nfs_verify_server_address(sap))
 			return -EINVAL;
 
-		rpc_set_port((struct sockaddr *)&args->nfs_server.address,
-				args->nfs_server.port);
-
-		nfs_validate_transport_protocol(args);
-
-		nfs4_validate_mount_flags(args);
-
-		if (args->auth_flavor_len > 1)
-			goto out_inval_auth;
-
-		if (args->client_address == NULL)
-			goto out_no_client_address;
-
-		status = nfs_parse_devname(dev_name,
-					   &args->nfs_server.hostname,
-					   NFS4_MAXNAMLEN,
-					   &args->nfs_server.export_path,
-					   NFS4_MAXPATHLEN);
-		if (status < 0)
-			return status;
-
-		break;
-		}
+		return nfs4_validate_text_mount_data(options, args, dev_name);
 	}
 
 	return 0;
@@ -2375,10 +2453,6 @@ out_inval_auth:
 out_no_address:
 	dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
 	return -EINVAL;
-
-out_no_client_address:
-	dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
-	return -EINVAL;
 }
 
 /*
@@ -2545,6 +2619,34 @@ out_err:
 	return ret;
 }
 
+static int nfs4_try_mount(int flags, const char *dev_name,
+			 struct nfs_parsed_mount_data *data,
+			 struct vfsmount *mnt)
+{
+	char *export_path;
+	struct vfsmount *root_mnt;
+	int error;
+
+	dfprintk(MOUNT, "--> nfs4_try_mount()\n");
+
+	export_path = data->nfs_server.export_path;
+	data->nfs_server.export_path = "/";
+	root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
+			data->nfs_server.hostname);
+	data->nfs_server.export_path = export_path;
+
+	error = PTR_ERR(root_mnt);
+	if (IS_ERR(root_mnt))
+		goto out;
+
+	error = nfs_follow_remote_path(root_mnt, export_path, mnt);
+
+out:
+	dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n", error,
+			error != 0 ? " [error]" : "");
+	return error;
+}
+
 /*
  * Get the superblock for an NFS4 mountpoint
  */
@@ -2552,8 +2654,6 @@ static int nfs4_get_sb(struct file_system_type *fs_type,
 	int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
 {
 	struct nfs_parsed_mount_data *data;
-	char *export_path;
-	struct vfsmount *root_mnt;
 	int error = -ENOMEM;
 
 	data = kzalloc(sizeof(*data), GFP_KERNEL);
@@ -2565,17 +2665,7 @@ static int nfs4_get_sb(struct file_system_type *fs_type,
 	if (error < 0)
 		goto out;
 
-	export_path = data->nfs_server.export_path;
-	data->nfs_server.export_path = "/";
-	root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
-			data->nfs_server.hostname);
-	data->nfs_server.export_path = export_path;
-
-	error = PTR_ERR(root_mnt);
-	if (IS_ERR(root_mnt))
-		goto out;
-
-	error = nfs_follow_remote_path(root_mnt, export_path, mnt);
+	error = nfs4_try_mount(flags, dev_name, data, mnt);
 
 out:
 	kfree(data->client_address);