1 files changed, 273 insertions, 270 deletions

diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index eb1c5979ecaf..c12dc680f8fe 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -1,4 +1,5 @@
-/**
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
  * eCryptfs: Linux filesystem encryption layer
  *
  * Copyright (C) 1997-2003 Erez Zadok
@@ -6,40 +7,26 @@
  * Copyright (C) 2004-2007 International Business Machines Corp.
  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
  *              Michael C. Thompson <mcthomps@us.ibm.com>
- *              Tyler Hicks <tyhicks@ou.edu>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
- * 02111-1307, USA.
+ *              Tyler Hicks <code@tyhicks.com>
  */
 
 #include <linux/dcache.h>
 #include <linux/file.h>
+#include <linux/fips.h>
 #include <linux/module.h>
 #include <linux/namei.h>
 #include <linux/skbuff.h>
-#include <linux/crypto.h>
-#include <linux/mount.h>
 #include <linux/pagemap.h>
 #include <linux/key.h>
-#include <linux/parser.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
 #include <linux/fs_stack.h>
+#include <linux/sysfs.h>
 #include <linux/slab.h>
 #include <linux/magic.h>
 #include "ecryptfs_kernel.h"
 
-/**
+/*
  * Module parameter that defines the ecryptfs_verbosity level.
  */
 int ecryptfs_verbosity = 0;
@@ -49,7 +36,7 @@ MODULE_PARM_DESC(ecryptfs_verbosity,
 		 "Initial verbosity level (0 or 1; defaults to "
 		 "0, which is Quiet)");
 
-/**
+/*
  * Module parameter that defines the number of message buffer elements
  */
 unsigned int ecryptfs_message_buf_len = ECRYPTFS_DEFAULT_MSG_CTX_ELEMS;
@@ -58,7 +45,7 @@ module_param(ecryptfs_message_buf_len, uint, 0);
 MODULE_PARM_DESC(ecryptfs_message_buf_len,
 		 "Number of message buffer elements");
 
-/**
+/*
  * Module parameter that defines the maximum guaranteed amount of time to wait
  * for a response from ecryptfsd.  The actual sleep time will be, more than
  * likely, a small amount greater than this specified value, but only less if
@@ -72,7 +59,7 @@ MODULE_PARM_DESC(ecryptfs_message_wait_timeout,
 		 "sleep while waiting for a message response from "
 		 "userspace");
 
-/**
+/*
  * Module parameter that is an estimate of the maximum number of users
  * that will be concurrently using eCryptfs. Set this to the right
  * value to balance performance and memory use.
@@ -95,7 +82,7 @@ void __ecryptfs_printk(const char *fmt, ...)
 	va_end(args);
 }
 
-/**
+/*
  * ecryptfs_init_lower_file
  * @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with
  *                   the lower dentry and the lower mount set
@@ -120,15 +107,14 @@ static int ecryptfs_init_lower_file(struct dentry *dentry,
 				    struct file **lower_file)
 {
 	const struct cred *cred = current_cred();
-	struct path *path = ecryptfs_dentry_to_lower_path(dentry);
+	struct path path = ecryptfs_lower_path(dentry);
 	int rc;
 
-	rc = ecryptfs_privileged_open(lower_file, path->dentry, path->mnt,
-				      cred);
+	rc = ecryptfs_privileged_open(lower_file, path.dentry, path.mnt, cred);
 	if (rc) {
 		printk(KERN_ERR "Error opening lower file "
 		       "for lower_dentry [0x%p] and lower_mnt [0x%p]; "
-		       "rc = [%d]\n", path->dentry, path->mnt, rc);
+		       "rc = [%d]\n", path.dentry, path.mnt, rc);
 		(*lower_file) = NULL;
 	}
 	return rc;
@@ -168,32 +154,30 @@ void ecryptfs_put_lower_file(struct inode *inode)
 	}
 }
 
-enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig,
-       ecryptfs_opt_cipher, ecryptfs_opt_ecryptfs_cipher,
-       ecryptfs_opt_ecryptfs_key_bytes,
-       ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata,
-       ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig,
-       ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes,
-       ecryptfs_opt_unlink_sigs, ecryptfs_opt_mount_auth_tok_only,
-       ecryptfs_opt_check_dev_ruid,
-       ecryptfs_opt_err };
-
-static const match_table_t tokens = {
-	{ecryptfs_opt_sig, "sig=%s"},
-	{ecryptfs_opt_ecryptfs_sig, "ecryptfs_sig=%s"},
-	{ecryptfs_opt_cipher, "cipher=%s"},
-	{ecryptfs_opt_ecryptfs_cipher, "ecryptfs_cipher=%s"},
-	{ecryptfs_opt_ecryptfs_key_bytes, "ecryptfs_key_bytes=%u"},
-	{ecryptfs_opt_passthrough, "ecryptfs_passthrough"},
-	{ecryptfs_opt_xattr_metadata, "ecryptfs_xattr_metadata"},
-	{ecryptfs_opt_encrypted_view, "ecryptfs_encrypted_view"},
-	{ecryptfs_opt_fnek_sig, "ecryptfs_fnek_sig=%s"},
-	{ecryptfs_opt_fn_cipher, "ecryptfs_fn_cipher=%s"},
-	{ecryptfs_opt_fn_cipher_key_bytes, "ecryptfs_fn_key_bytes=%u"},
-	{ecryptfs_opt_unlink_sigs, "ecryptfs_unlink_sigs"},
-	{ecryptfs_opt_mount_auth_tok_only, "ecryptfs_mount_auth_tok_only"},
-	{ecryptfs_opt_check_dev_ruid, "ecryptfs_check_dev_ruid"},
-	{ecryptfs_opt_err, NULL}
+enum {
+	Opt_sig, Opt_ecryptfs_sig, Opt_cipher, Opt_ecryptfs_cipher,
+	Opt_ecryptfs_key_bytes, Opt_passthrough, Opt_xattr_metadata,
+	Opt_encrypted_view, Opt_fnek_sig, Opt_fn_cipher,
+	Opt_fn_cipher_key_bytes, Opt_unlink_sigs, Opt_mount_auth_tok_only,
+	Opt_check_dev_ruid
+};
+
+static const struct fs_parameter_spec ecryptfs_fs_param_spec[] = {
+	fsparam_string	("sig",			    Opt_sig),
+	fsparam_string	("ecryptfs_sig",	    Opt_ecryptfs_sig),
+	fsparam_string	("cipher",		    Opt_cipher),
+	fsparam_string	("ecryptfs_cipher",	    Opt_ecryptfs_cipher),
+	fsparam_u32	("ecryptfs_key_bytes",	    Opt_ecryptfs_key_bytes),
+	fsparam_flag	("ecryptfs_passthrough",    Opt_passthrough),
+	fsparam_flag	("ecryptfs_xattr_metadata", Opt_xattr_metadata),
+	fsparam_flag	("ecryptfs_encrypted_view", Opt_encrypted_view),
+	fsparam_string	("ecryptfs_fnek_sig",	    Opt_fnek_sig),
+	fsparam_string	("ecryptfs_fn_cipher",	    Opt_fn_cipher),
+	fsparam_u32	("ecryptfs_fn_key_bytes",   Opt_fn_cipher_key_bytes),
+	fsparam_flag	("ecryptfs_unlink_sigs",    Opt_unlink_sigs),
+	fsparam_flag	("ecryptfs_mount_auth_tok_only", Opt_mount_auth_tok_only),
+	fsparam_flag	("ecryptfs_check_dev_ruid", Opt_check_dev_ruid),
+	{}
 };
 
 static int ecryptfs_init_global_auth_toks(
@@ -234,19 +218,20 @@ static void ecryptfs_init_mount_crypt_stat(
 	mount_crypt_stat->flags |= ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED;
 }
 
+struct ecryptfs_fs_context {
+	/* Mount option status trackers */
+	bool check_ruid;
+	bool sig_set;
+	bool cipher_name_set;
+	bool cipher_key_bytes_set;
+	bool fn_cipher_name_set;
+	bool fn_cipher_key_bytes_set;
+};
+
 /**
- * ecryptfs_parse_options
- * @sb: The ecryptfs super block
- * @options: The options passed to the kernel
- * @check_ruid: set to 1 if device uid should be checked against the ruid
- *
- * Parse mount options:
- * debug=N 	   - ecryptfs_verbosity level for debug output
- * sig=XXX	   - description(signature) of the key to use
- *
- * Returns the dentry object of the lower-level (lower/interposed)
- * directory; We want to mount our stackable file system on top of
- * that lower directory.
+ * ecryptfs_parse_param
+ * @fc: The ecryptfs filesystem context
+ * @param: The mount parameter to parse
  *
  * The signature of the key to use must be the description of a key
  * already in the keyring. Mounting will fail if the key can not be
@@ -254,171 +239,132 @@ static void ecryptfs_init_mount_crypt_stat(
  *
  * Returns zero on success; non-zero on error
  */
-static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options,
-				  uid_t *check_ruid)
+static int ecryptfs_parse_param(
+	struct fs_context *fc,
+	struct fs_parameter *param)
 {
-	char *p;
-	int rc = 0;
-	int sig_set = 0;
-	int cipher_name_set = 0;
-	int fn_cipher_name_set = 0;
-	int cipher_key_bytes;
-	int cipher_key_bytes_set = 0;
-	int fn_cipher_key_bytes;
-	int fn_cipher_key_bytes_set = 0;
+	int rc;
+	int opt;
+	struct fs_parse_result result;
+	struct ecryptfs_fs_context *ctx = fc->fs_private;
+	struct ecryptfs_sb_info *sbi = fc->s_fs_info;
 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
 		&sbi->mount_crypt_stat;
-	substring_t args[MAX_OPT_ARGS];
-	int token;
-	char *sig_src;
-	char *cipher_name_dst;
-	char *cipher_name_src;
-	char *fn_cipher_name_dst;
-	char *fn_cipher_name_src;
-	char *fnek_dst;
-	char *fnek_src;
-	char *cipher_key_bytes_src;
-	char *fn_cipher_key_bytes_src;
-	u8 cipher_code;
 
-	*check_ruid = 0;
+	opt = fs_parse(fc, ecryptfs_fs_param_spec, param, &result);
+	if (opt < 0)
+		return opt;
 
-	if (!options) {
-		rc = -EINVAL;
-		goto out;
-	}
-	ecryptfs_init_mount_crypt_stat(mount_crypt_stat);
-	while ((p = strsep(&options, ",")) != NULL) {
-		if (!*p)
-			continue;
-		token = match_token(p, tokens, args);
-		switch (token) {
-		case ecryptfs_opt_sig:
-		case ecryptfs_opt_ecryptfs_sig:
-			sig_src = args[0].from;
-			rc = ecryptfs_add_global_auth_tok(mount_crypt_stat,
-							  sig_src, 0);
-			if (rc) {
-				printk(KERN_ERR "Error attempting to register "
-				       "global sig; rc = [%d]\n", rc);
-				goto out;
-			}
-			sig_set = 1;
-			break;
-		case ecryptfs_opt_cipher:
-		case ecryptfs_opt_ecryptfs_cipher:
-			cipher_name_src = args[0].from;
-			cipher_name_dst =
-				mount_crypt_stat->
-				global_default_cipher_name;
-			strncpy(cipher_name_dst, cipher_name_src,
-				ECRYPTFS_MAX_CIPHER_NAME_SIZE);
-			cipher_name_dst[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
-			cipher_name_set = 1;
-			break;
-		case ecryptfs_opt_ecryptfs_key_bytes:
-			cipher_key_bytes_src = args[0].from;
-			cipher_key_bytes =
-				(int)simple_strtol(cipher_key_bytes_src,
-						   &cipher_key_bytes_src, 0);
-			mount_crypt_stat->global_default_cipher_key_size =
-				cipher_key_bytes;
-			cipher_key_bytes_set = 1;
-			break;
-		case ecryptfs_opt_passthrough:
-			mount_crypt_stat->flags |=
-				ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED;
-			break;
-		case ecryptfs_opt_xattr_metadata:
-			mount_crypt_stat->flags |=
-				ECRYPTFS_XATTR_METADATA_ENABLED;
-			break;
-		case ecryptfs_opt_encrypted_view:
-			mount_crypt_stat->flags |=
-				ECRYPTFS_XATTR_METADATA_ENABLED;
-			mount_crypt_stat->flags |=
-				ECRYPTFS_ENCRYPTED_VIEW_ENABLED;
-			break;
-		case ecryptfs_opt_fnek_sig:
-			fnek_src = args[0].from;
-			fnek_dst =
-				mount_crypt_stat->global_default_fnek_sig;
-			strncpy(fnek_dst, fnek_src, ECRYPTFS_SIG_SIZE_HEX);
-			mount_crypt_stat->global_default_fnek_sig[
-				ECRYPTFS_SIG_SIZE_HEX] = '\0';
-			rc = ecryptfs_add_global_auth_tok(
-				mount_crypt_stat,
-				mount_crypt_stat->global_default_fnek_sig,
-				ECRYPTFS_AUTH_TOK_FNEK);
-			if (rc) {
-				printk(KERN_ERR "Error attempting to register "
-				       "global fnek sig [%s]; rc = [%d]\n",
-				       mount_crypt_stat->global_default_fnek_sig,
-				       rc);
-				goto out;
-			}
-			mount_crypt_stat->flags |=
-				(ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES
-				 | ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK);
-			break;
-		case ecryptfs_opt_fn_cipher:
-			fn_cipher_name_src = args[0].from;
-			fn_cipher_name_dst =
-				mount_crypt_stat->global_default_fn_cipher_name;
-			strncpy(fn_cipher_name_dst, fn_cipher_name_src,
-				ECRYPTFS_MAX_CIPHER_NAME_SIZE);
-			mount_crypt_stat->global_default_fn_cipher_name[
-				ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
-			fn_cipher_name_set = 1;
-			break;
-		case ecryptfs_opt_fn_cipher_key_bytes:
-			fn_cipher_key_bytes_src = args[0].from;
-			fn_cipher_key_bytes =
-				(int)simple_strtol(fn_cipher_key_bytes_src,
-						   &fn_cipher_key_bytes_src, 0);
-			mount_crypt_stat->global_default_fn_cipher_key_bytes =
-				fn_cipher_key_bytes;
-			fn_cipher_key_bytes_set = 1;
-			break;
-		case ecryptfs_opt_unlink_sigs:
-			mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS;
-			break;
-		case ecryptfs_opt_mount_auth_tok_only:
-			mount_crypt_stat->flags |=
-				ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY;
-			break;
-		case ecryptfs_opt_check_dev_ruid:
-			*check_ruid = 1;
-			break;
-		case ecryptfs_opt_err:
-		default:
-			printk(KERN_WARNING
-			       "%s: eCryptfs: unrecognized option [%s]\n",
-			       __func__, p);
+	switch (opt) {
+	case Opt_sig:
+	case Opt_ecryptfs_sig:
+		rc = ecryptfs_add_global_auth_tok(mount_crypt_stat,
+						  param->string, 0);
+		if (rc) {
+			printk(KERN_ERR "Error attempting to register "
+			       "global sig; rc = [%d]\n", rc);
+			return rc;
+		}
+		ctx->sig_set = 1;
+		break;
+	case Opt_cipher:
+	case Opt_ecryptfs_cipher:
+		strscpy(mount_crypt_stat->global_default_cipher_name,
+			param->string);
+		ctx->cipher_name_set = 1;
+		break;
+	case Opt_ecryptfs_key_bytes:
+		mount_crypt_stat->global_default_cipher_key_size =
+			result.uint_32;
+		ctx->cipher_key_bytes_set = 1;
+		break;
+	case Opt_passthrough:
+		mount_crypt_stat->flags |=
+			ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED;
+		break;
+	case Opt_xattr_metadata:
+		mount_crypt_stat->flags |= ECRYPTFS_XATTR_METADATA_ENABLED;
+		break;
+	case Opt_encrypted_view:
+		mount_crypt_stat->flags |= ECRYPTFS_XATTR_METADATA_ENABLED;
+		mount_crypt_stat->flags |= ECRYPTFS_ENCRYPTED_VIEW_ENABLED;
+		break;
+	case Opt_fnek_sig:
+		strscpy(mount_crypt_stat->global_default_fnek_sig,
+			param->string);
+		rc = ecryptfs_add_global_auth_tok(
+			mount_crypt_stat,
+			mount_crypt_stat->global_default_fnek_sig,
+			ECRYPTFS_AUTH_TOK_FNEK);
+		if (rc) {
+			printk(KERN_ERR "Error attempting to register "
+			       "global fnek sig [%s]; rc = [%d]\n",
+			       mount_crypt_stat->global_default_fnek_sig, rc);
+			return rc;
 		}
+		mount_crypt_stat->flags |=
+			(ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES
+			 | ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK);
+		break;
+	case Opt_fn_cipher:
+		strscpy(mount_crypt_stat->global_default_fn_cipher_name,
+			param->string);
+		ctx->fn_cipher_name_set = 1;
+		break;
+	case Opt_fn_cipher_key_bytes:
+		mount_crypt_stat->global_default_fn_cipher_key_bytes =
+			result.uint_32;
+		ctx->fn_cipher_key_bytes_set = 1;
+		break;
+	case Opt_unlink_sigs:
+		mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS;
+		break;
+	case Opt_mount_auth_tok_only:
+		mount_crypt_stat->flags |= ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY;
+		break;
+	case Opt_check_dev_ruid:
+		ctx->check_ruid = 1;
+		break;
+	default:
+		return -EINVAL;
 	}
-	if (!sig_set) {
+
+	return 0;
+}
+
+static int ecryptfs_validate_options(struct fs_context *fc)
+{
+	int rc = 0;
+	u8 cipher_code;
+	struct ecryptfs_fs_context *ctx = fc->fs_private;
+	struct ecryptfs_sb_info *sbi = fc->s_fs_info;
+	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+
+
+	mount_crypt_stat = &sbi->mount_crypt_stat;
+
+	if (!ctx->sig_set) {
 		rc = -EINVAL;
 		ecryptfs_printk(KERN_ERR, "You must supply at least one valid "
 				"auth tok signature as a mount "
 				"parameter; see the eCryptfs README\n");
 		goto out;
 	}
-	if (!cipher_name_set) {
+	if (!ctx->cipher_name_set) {
 		int cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER);
 
-		BUG_ON(cipher_name_len >= ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+		BUG_ON(cipher_name_len > ECRYPTFS_MAX_CIPHER_NAME_SIZE);
 		strcpy(mount_crypt_stat->global_default_cipher_name,
 		       ECRYPTFS_DEFAULT_CIPHER);
 	}
 	if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
-	    && !fn_cipher_name_set)
+	    && !ctx->fn_cipher_name_set)
 		strcpy(mount_crypt_stat->global_default_fn_cipher_name,
 		       mount_crypt_stat->global_default_cipher_name);
-	if (!cipher_key_bytes_set)
+	if (!ctx->cipher_key_bytes_set)
 		mount_crypt_stat->global_default_cipher_key_size = 0;
 	if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
-	    && !fn_cipher_key_bytes_set)
+	    && !ctx->fn_cipher_key_bytes_set)
 		mount_crypt_stat->global_default_fn_cipher_key_bytes =
 			mount_crypt_stat->global_default_cipher_key_size;
 
@@ -427,7 +373,7 @@ static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options,
 		mount_crypt_stat->global_default_cipher_key_size);
 	if (!cipher_code) {
 		ecryptfs_printk(KERN_ERR,
-				"eCryptfs doesn't support cipher: %s",
+				"eCryptfs doesn't support cipher: %s\n",
 				mount_crypt_stat->global_default_cipher_name);
 		rc = -EINVAL;
 		goto out;
@@ -481,57 +427,60 @@ out:
 struct kmem_cache *ecryptfs_sb_info_cache;
 static struct file_system_type ecryptfs_fs_type;
 
-/**
- * ecryptfs_get_sb
- * @fs_type
- * @flags
- * @dev_name: The path to mount over
- * @raw_data: The options passed into the kernel
+/*
+ * ecryptfs_get_tree
+ * @fc: The filesystem context
  */
-static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags,
-			const char *dev_name, void *raw_data)
+static int ecryptfs_get_tree(struct fs_context *fc)
 {
 	struct super_block *s;
-	struct ecryptfs_sb_info *sbi;
-	struct ecryptfs_dentry_info *root_info;
+	struct ecryptfs_fs_context *ctx = fc->fs_private;
+	struct ecryptfs_sb_info *sbi = fc->s_fs_info;
+	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 	const char *err = "Getting sb failed";
 	struct inode *inode;
 	struct path path;
-	uid_t check_ruid;
 	int rc;
 
-	sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL);
-	if (!sbi) {
-		rc = -ENOMEM;
+	if (!fc->source) {
+		rc = -EINVAL;
+		err = "Device name cannot be null";
 		goto out;
 	}
 
-	rc = ecryptfs_parse_options(sbi, raw_data, &check_ruid);
+	mount_crypt_stat = &sbi->mount_crypt_stat;
+	rc = ecryptfs_validate_options(fc);
 	if (rc) {
-		err = "Error parsing options";
+		err = "Error validating options";
 		goto out;
 	}
 
-	s = sget(fs_type, NULL, set_anon_super, flags, NULL);
+	if (fips_enabled) {
+		rc = -EINVAL;
+		err = "eCryptfs support is disabled due to FIPS";
+		goto out;
+	}
+
+	s = sget_fc(fc, NULL, set_anon_super_fc);
 	if (IS_ERR(s)) {
 		rc = PTR_ERR(s);
 		goto out;
 	}
 
-	rc = bdi_setup_and_register(&sbi->bdi, "ecryptfs", BDI_CAP_MAP_COPY);
+	rc = super_setup_bdi(s);
 	if (rc)
 		goto out1;
 
 	ecryptfs_set_superblock_private(s, sbi);
-	s->s_bdi = &sbi->bdi;
 
 	/* ->kill_sb() will take care of sbi after that point */
 	sbi = NULL;
 	s->s_op = &ecryptfs_sops;
-	s->s_d_op = &ecryptfs_dops;
+	s->s_xattr = ecryptfs_xattr_handlers;
+	set_default_d_op(s, &ecryptfs_dops);
 
 	err = "Reading sb failed";
-	rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
+	rc = kern_path(fc->source, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
 	if (rc) {
 		ecryptfs_printk(KERN_WARNING, "kern_path() failed\n");
 		goto out1;
@@ -544,11 +493,18 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
 		goto out_free;
 	}
 
-	if (check_ruid && !uid_eq(path.dentry->d_inode->i_uid, current_uid())) {
+	if (is_idmapped_mnt(path.mnt)) {
+		rc = -EINVAL;
+		printk(KERN_ERR "Mounting on idmapped mounts currently disallowed\n");
+		goto out_free;
+	}
+
+	if (ctx->check_ruid &&
+	    !uid_eq(d_inode(path.dentry)->i_uid, current_uid())) {
 		rc = -EPERM;
 		printk(KERN_ERR "Mount of device (uid: %d) not owned by "
 		       "requested user (uid: %d)\n",
-			i_uid_read(path.dentry->d_inode),
+			i_uid_read(d_inode(path.dentry)),
 			from_kuid(&init_user_ns, current_uid()));
 		goto out_free;
 	}
@@ -557,17 +513,31 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
 
 	/**
 	 * Set the POSIX ACL flag based on whether they're enabled in the lower
-	 * mount. Force a read-only eCryptfs mount if the lower mount is ro.
-	 * Allow a ro eCryptfs mount even when the lower mount is rw.
+	 * mount.
 	 */
-	s->s_flags = flags & ~MS_POSIXACL;
-	s->s_flags |= path.dentry->d_sb->s_flags & (MS_RDONLY | MS_POSIXACL);
+	s->s_flags = fc->sb_flags & ~SB_POSIXACL;
+	s->s_flags |= path.dentry->d_sb->s_flags & SB_POSIXACL;
+
+	/**
+	 * Force a read-only eCryptfs mount when:
+	 *   1) The lower mount is ro
+	 *   2) The ecryptfs_encrypted_view mount option is specified
+	 */
+	if (sb_rdonly(path.dentry->d_sb) || mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
+		s->s_flags |= SB_RDONLY;
 
 	s->s_maxbytes = path.dentry->d_sb->s_maxbytes;
 	s->s_blocksize = path.dentry->d_sb->s_blocksize;
 	s->s_magic = ECRYPTFS_SUPER_MAGIC;
+	s->s_stack_depth = path.dentry->d_sb->s_stack_depth + 1;
+
+	rc = -EINVAL;
+	if (s->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
+		pr_err("eCryptfs: maximum fs stacking depth exceeded\n");
+		goto out_free;
+	}
 
-	inode = ecryptfs_get_inode(path.dentry->d_inode, s);
+	inode = ecryptfs_get_inode(d_inode(path.dentry), s);
 	rc = PTR_ERR(inode);
 	if (IS_ERR(inode))
 		goto out_free;
@@ -578,30 +548,23 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
 		goto out_free;
 	}
 
-	rc = -ENOMEM;
-	root_info = kmem_cache_zalloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
-	if (!root_info)
-		goto out_free;
-
-	/* ->kill_sb() will take care of root_info */
-	ecryptfs_set_dentry_private(s->s_root, root_info);
 	ecryptfs_set_dentry_lower(s->s_root, path.dentry);
-	ecryptfs_set_dentry_lower_mnt(s->s_root, path.mnt);
+	ecryptfs_superblock_to_private(s)->lower_mnt = path.mnt;
 
-	s->s_flags |= MS_ACTIVE;
-	return dget(s->s_root);
+	s->s_flags |= SB_ACTIVE;
+	fc->root = dget(s->s_root);
+	return 0;
 
 out_free:
 	path_put(&path);
 out1:
 	deactivate_locked_super(s);
 out:
-	if (sbi) {
+	if (sbi)
 		ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat);
-		kmem_cache_free(ecryptfs_sb_info_cache, sbi);
-	}
+
 	printk(KERN_ERR "%s; rc = [%d]\n", err, rc);
-	return ERR_PTR(rc);
+	return rc;
 }
 
 /**
@@ -616,21 +579,65 @@ static void ecryptfs_kill_block_super(struct super_block *sb)
 	kill_anon_super(sb);
 	if (!sb_info)
 		return;
+	mntput(sb_info->lower_mnt);
 	ecryptfs_destroy_mount_crypt_stat(&sb_info->mount_crypt_stat);
-	bdi_destroy(&sb_info->bdi);
 	kmem_cache_free(ecryptfs_sb_info_cache, sb_info);
 }
 
+static void ecryptfs_free_fc(struct fs_context *fc)
+{
+	struct ecryptfs_fs_context *ctx = fc->fs_private;
+	struct ecryptfs_sb_info *sbi = fc->s_fs_info;
+
+	kfree(ctx);
+
+	if (sbi) {
+		ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat);
+		kmem_cache_free(ecryptfs_sb_info_cache, sbi);
+	}
+}
+
+static const struct fs_context_operations ecryptfs_context_ops = {
+	.free		= ecryptfs_free_fc,
+	.parse_param	= ecryptfs_parse_param,
+	.get_tree	= ecryptfs_get_tree,
+	.reconfigure	= NULL,
+};
+
+static int ecryptfs_init_fs_context(struct fs_context *fc)
+{
+	struct ecryptfs_fs_context *ctx;
+	struct ecryptfs_sb_info *sbi = NULL;
+
+	ctx = kzalloc(sizeof(struct ecryptfs_fs_context), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+	sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL);
+	if (!sbi) {
+		kfree(ctx);
+		ctx = NULL;
+		return -ENOMEM;
+	}
+
+	ecryptfs_init_mount_crypt_stat(&sbi->mount_crypt_stat);
+
+	fc->fs_private = ctx;
+	fc->s_fs_info = sbi;
+	fc->ops = &ecryptfs_context_ops;
+	return 0;
+}
+
 static struct file_system_type ecryptfs_fs_type = {
 	.owner = THIS_MODULE,
 	.name = "ecryptfs",
-	.mount = ecryptfs_mount,
+	.init_fs_context = ecryptfs_init_fs_context,
+	.parameters = ecryptfs_fs_param_spec,
 	.kill_sb = ecryptfs_kill_block_super,
 	.fs_flags = 0
 };
 MODULE_ALIAS_FS("ecryptfs");
 
-/**
+/*
  * inode_info_init_once
  *
  * Initializes the ecryptfs_inode_info_cache when it is created
@@ -647,6 +654,7 @@ static struct ecryptfs_cache_info {
 	struct kmem_cache **cache;
 	const char *name;
 	size_t size;
+	slab_flags_t flags;
 	void (*ctor)(void *obj);
 } ecryptfs_cache_infos[] = {
 	{
@@ -660,14 +668,10 @@ static struct ecryptfs_cache_info {
 		.size = sizeof(struct ecryptfs_file_info),
 	},
 	{
-		.cache = &ecryptfs_dentry_info_cache,
-		.name = "ecryptfs_dentry_info_cache",
-		.size = sizeof(struct ecryptfs_dentry_info),
-	},
-	{
 		.cache = &ecryptfs_inode_info_cache,
 		.name = "ecryptfs_inode_cache",
 		.size = sizeof(struct ecryptfs_inode_info),
+		.flags = SLAB_ACCOUNT,
 		.ctor = inode_info_init_once,
 	},
 	{
@@ -678,12 +682,12 @@ static struct ecryptfs_cache_info {
 	{
 		.cache = &ecryptfs_header_cache,
 		.name = "ecryptfs_headers",
-		.size = PAGE_CACHE_SIZE,
+		.size = PAGE_SIZE,
 	},
 	{
 		.cache = &ecryptfs_xattr_cache,
 		.name = "ecryptfs_xattr_cache",
-		.size = PAGE_CACHE_SIZE,
+		.size = PAGE_SIZE,
 	},
 	{
 		.cache = &ecryptfs_key_record_cache,
@@ -721,8 +725,7 @@ static void ecryptfs_free_kmem_caches(void)
 		struct ecryptfs_cache_info *info;
 
 		info = &ecryptfs_cache_infos[i];
-		if (*(info->cache))
-			kmem_cache_destroy(*(info->cache));
+		kmem_cache_destroy(*(info->cache));
 	}
 }
 
@@ -739,8 +742,8 @@ static int ecryptfs_init_kmem_caches(void)
 		struct ecryptfs_cache_info *info;
 
 		info = &ecryptfs_cache_infos[i];
-		*(info->cache) = kmem_cache_create(info->name, info->size,
-				0, SLAB_HWCACHE_ALIGN, info->ctor);
+		*(info->cache) = kmem_cache_create(info->name, info->size, 0,
+				SLAB_HWCACHE_ALIGN | info->flags, info->ctor);
 		if (!*(info->cache)) {
 			ecryptfs_free_kmem_caches();
 			ecryptfs_printk(KERN_WARNING, "%s: "
@@ -757,7 +760,7 @@ static struct kobject *ecryptfs_kobj;
 static ssize_t version_show(struct kobject *kobj,
 			    struct kobj_attribute *attr, char *buff)
 {
-	return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK);
+	return sysfs_emit(buff, "%d\n", ECRYPTFS_VERSIONING_MASK);
 }
 
 static struct kobj_attribute version_attr = __ATTR_RO(version);
@@ -767,7 +770,7 @@ static struct attribute *attributes[] = {
 	NULL,
 };
 
-static struct attribute_group attr_group = {
+static const struct attribute_group attr_group = {
 	.attrs = attributes,
 };
 
@@ -801,7 +804,7 @@ static int __init ecryptfs_init(void)
 {
 	int rc;
 
-	if (ECRYPTFS_DEFAULT_EXTENT_SIZE > PAGE_CACHE_SIZE) {
+	if (ECRYPTFS_DEFAULT_EXTENT_SIZE > PAGE_SIZE) {
 		rc = -EINVAL;
 		ecryptfs_printk(KERN_ERR, "The eCryptfs extent size is "
 				"larger than the host's page size, and so "
@@ -809,7 +812,7 @@ static int __init ecryptfs_init(void)
 				"default eCryptfs extent size is [%u] bytes; "
 				"the page size is [%lu] bytes.\n",
 				ECRYPTFS_DEFAULT_EXTENT_SIZE,
-				(unsigned long)PAGE_CACHE_SIZE);
+				(unsigned long)PAGE_SIZE);
 		goto out;
 	}
 	rc = ecryptfs_init_kmem_caches();