Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 895 insertions, 0 deletions

diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
new file mode 100644
index 000000000..5f37cddb9
--- /dev/null
+++ b/fs/ecryptfs/main.c
@@ -0,0 +1,895 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * 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 <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/pagemap.h>
+#include <linux/key.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/string.h>
+#include <linux/magic.h>
+#include "ecryptfs_kernel.h"
+
+/*
+ * Module parameter that defines the ecryptfs_verbosity level.
+ */
+int ecryptfs_verbosity = 0;
+
+module_param(ecryptfs_verbosity, int, 0);
+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;
+
+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
+ * the message successfully arrives.
+ */
+signed long ecryptfs_message_wait_timeout = ECRYPTFS_MAX_MSG_CTX_TTL / HZ;
+
+module_param(ecryptfs_message_wait_timeout, long, 0);
+MODULE_PARM_DESC(ecryptfs_message_wait_timeout,
+		 "Maximum number of seconds that an operation will "
+		 "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.
+ */
+unsigned int ecryptfs_number_of_users = ECRYPTFS_DEFAULT_NUM_USERS;
+
+module_param(ecryptfs_number_of_users, uint, 0);
+MODULE_PARM_DESC(ecryptfs_number_of_users, "An estimate of the number of "
+		 "concurrent users of eCryptfs");
+
+void __ecryptfs_printk(const char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	if (fmt[1] == '7') { /* KERN_DEBUG */
+		if (ecryptfs_verbosity >= 1)
+			vprintk(fmt, args);
+	} else
+		vprintk(fmt, args);
+	va_end(args);
+}
+
+/*
+ * ecryptfs_init_lower_file
+ * @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with
+ *                   the lower dentry and the lower mount set
+ *
+ * eCryptfs only ever keeps a single open file for every lower
+ * inode. All I/O operations to the lower inode occur through that
+ * file. When the first eCryptfs dentry that interposes with the first
+ * lower dentry for that inode is created, this function creates the
+ * lower file struct and associates it with the eCryptfs
+ * inode. When all eCryptfs files associated with the inode are released, the
+ * file is closed.
+ *
+ * The lower file will be opened with read/write permissions, if
+ * possible. Otherwise, it is opened read-only.
+ *
+ * This function does nothing if a lower file is already
+ * associated with the eCryptfs inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_init_lower_file(struct dentry *dentry,
+				    struct file **lower_file)
+{
+	const struct cred *cred = current_cred();
+	struct path path = ecryptfs_lower_path(dentry);
+	int rc;
+
+	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);
+		(*lower_file) = NULL;
+	}
+	return rc;
+}
+
+int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode)
+{
+	struct ecryptfs_inode_info *inode_info;
+	int count, rc = 0;
+
+	inode_info = ecryptfs_inode_to_private(inode);
+	mutex_lock(&inode_info->lower_file_mutex);
+	count = atomic_inc_return(&inode_info->lower_file_count);
+	if (WARN_ON_ONCE(count < 1))
+		rc = -EINVAL;
+	else if (count == 1) {
+		rc = ecryptfs_init_lower_file(dentry,
+					      &inode_info->lower_file);
+		if (rc)
+			atomic_set(&inode_info->lower_file_count, 0);
+	}
+	mutex_unlock(&inode_info->lower_file_mutex);
+	return rc;
+}
+
+void ecryptfs_put_lower_file(struct inode *inode)
+{
+	struct ecryptfs_inode_info *inode_info;
+
+	inode_info = ecryptfs_inode_to_private(inode);
+	if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count,
+				      &inode_info->lower_file_mutex)) {
+		filemap_write_and_wait(inode->i_mapping);
+		fput(inode_info->lower_file);
+		inode_info->lower_file = NULL;
+		mutex_unlock(&inode_info->lower_file_mutex);
+	}
+}
+
+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(
+	struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+	struct ecryptfs_global_auth_tok *global_auth_tok;
+	struct ecryptfs_auth_tok *auth_tok;
+	int rc = 0;
+
+	list_for_each_entry(global_auth_tok,
+			    &mount_crypt_stat->global_auth_tok_list,
+			    mount_crypt_stat_list) {
+		rc = ecryptfs_keyring_auth_tok_for_sig(
+			&global_auth_tok->global_auth_tok_key, &auth_tok,
+			global_auth_tok->sig);
+		if (rc) {
+			printk(KERN_ERR "Could not find valid key in user "
+			       "session keyring for sig specified in mount "
+			       "option: [%s]\n", global_auth_tok->sig);
+			global_auth_tok->flags |= ECRYPTFS_AUTH_TOK_INVALID;
+			goto out;
+		} else {
+			global_auth_tok->flags &= ~ECRYPTFS_AUTH_TOK_INVALID;
+			up_write(&(global_auth_tok->global_auth_tok_key)->sem);
+		}
+	}
+out:
+	return rc;
+}
+
+static void ecryptfs_init_mount_crypt_stat(
+	struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+	memset((void *)mount_crypt_stat, 0,
+	       sizeof(struct ecryptfs_mount_crypt_stat));
+	INIT_LIST_HEAD(&mount_crypt_stat->global_auth_tok_list);
+	mutex_init(&mount_crypt_stat->global_auth_tok_list_mutex);
+	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_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
+ * found.
+ *
+ * Returns zero on success; non-zero on error
+ */
+static int ecryptfs_parse_param(
+	struct fs_context *fc,
+	struct fs_parameter *param)
+{
+	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;
+
+	opt = fs_parse(fc, ecryptfs_fs_param_spec, param, &result);
+	if (opt < 0)
+		return opt;
+
+	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;
+	}
+
+	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 (!ctx->cipher_name_set) {
+		int cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER);
+
+		BUG_ON(cipher_name_len > ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+		strscpy(mount_crypt_stat->global_default_cipher_name,
+			ECRYPTFS_DEFAULT_CIPHER);
+	}
+	if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+	    && !ctx->fn_cipher_name_set)
+		strscpy(mount_crypt_stat->global_default_fn_cipher_name,
+			mount_crypt_stat->global_default_cipher_name);
+	if (!ctx->cipher_key_bytes_set)
+		mount_crypt_stat->global_default_cipher_key_size = 0;
+	if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+	    && !ctx->fn_cipher_key_bytes_set)
+		mount_crypt_stat->global_default_fn_cipher_key_bytes =
+			mount_crypt_stat->global_default_cipher_key_size;
+
+	cipher_code = ecryptfs_code_for_cipher_string(
+		mount_crypt_stat->global_default_cipher_name,
+		mount_crypt_stat->global_default_cipher_key_size);
+	if (!cipher_code) {
+		ecryptfs_printk(KERN_ERR,
+				"eCryptfs doesn't support cipher: %s\n",
+				mount_crypt_stat->global_default_cipher_name);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	mutex_lock(&key_tfm_list_mutex);
+	if (!ecryptfs_tfm_exists(mount_crypt_stat->global_default_cipher_name,
+				 NULL)) {
+		rc = ecryptfs_add_new_key_tfm(
+			NULL, mount_crypt_stat->global_default_cipher_name,
+			mount_crypt_stat->global_default_cipher_key_size);
+		if (rc) {
+			printk(KERN_ERR "Error attempting to initialize "
+			       "cipher with name = [%s] and key size = [%td]; "
+			       "rc = [%d]\n",
+			       mount_crypt_stat->global_default_cipher_name,
+			       mount_crypt_stat->global_default_cipher_key_size,
+			       rc);
+			rc = -EINVAL;
+			mutex_unlock(&key_tfm_list_mutex);
+			goto out;
+		}
+	}
+	if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+	    && !ecryptfs_tfm_exists(
+		    mount_crypt_stat->global_default_fn_cipher_name, NULL)) {
+		rc = ecryptfs_add_new_key_tfm(
+			NULL, mount_crypt_stat->global_default_fn_cipher_name,
+			mount_crypt_stat->global_default_fn_cipher_key_bytes);
+		if (rc) {
+			printk(KERN_ERR "Error attempting to initialize "
+			       "cipher with name = [%s] and key size = [%td]; "
+			       "rc = [%d]\n",
+			       mount_crypt_stat->global_default_fn_cipher_name,
+			       mount_crypt_stat->global_default_fn_cipher_key_bytes,
+			       rc);
+			rc = -EINVAL;
+			mutex_unlock(&key_tfm_list_mutex);
+			goto out;
+		}
+	}
+	mutex_unlock(&key_tfm_list_mutex);
+	rc = ecryptfs_init_global_auth_toks(mount_crypt_stat);
+	if (rc)
+		printk(KERN_WARNING "One or more global auth toks could not "
+		       "properly register; rc = [%d]\n", rc);
+out:
+	return rc;
+}
+
+struct kmem_cache *ecryptfs_sb_info_cache;
+static struct file_system_type ecryptfs_fs_type;
+
+/*
+ * ecryptfs_get_tree
+ * @fc: The filesystem context
+ */
+static int ecryptfs_get_tree(struct fs_context *fc)
+{
+	struct super_block *s;
+	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;
+	int rc;
+
+	if (!fc->source) {
+		rc = -EINVAL;
+		err = "Device name cannot be null";
+		goto out;
+	}
+
+	mount_crypt_stat = &sbi->mount_crypt_stat;
+	rc = ecryptfs_validate_options(fc);
+	if (rc) {
+		err = "Error validating options";
+		goto out;
+	}
+
+	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 = super_setup_bdi(s);
+	if (rc)
+		goto out1;
+
+	ecryptfs_set_superblock_private(s, sbi);
+
+	/* ->kill_sb() will take care of sbi after that point */
+	sbi = NULL;
+	s->s_op = &ecryptfs_sops;
+	s->s_xattr = ecryptfs_xattr_handlers;
+	set_default_d_op(s, &ecryptfs_dops);
+
+	err = "Reading sb failed";
+	rc = kern_path(fc->source, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
+	if (rc) {
+		ecryptfs_printk(KERN_WARNING, "kern_path() failed\n");
+		goto out1;
+	}
+	if (path.dentry->d_sb->s_type == &ecryptfs_fs_type) {
+		rc = -EINVAL;
+		printk(KERN_ERR "Mount on filesystem of type "
+			"eCryptfs explicitly disallowed due to "
+			"known incompatibilities\n");
+		goto out_free;
+	}
+
+	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(d_inode(path.dentry)),
+			from_kuid(&init_user_ns, current_uid()));
+		goto out_free;
+	}
+
+	ecryptfs_set_superblock_lower(s, path.dentry->d_sb);
+
+	/**
+	 * Set the POSIX ACL flag based on whether they're enabled in the lower
+	 * mount.
+	 */
+	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;
+	s->s_time_gran = path.dentry->d_sb->s_time_gran;
+
+	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(d_inode(path.dentry), s);
+	rc = PTR_ERR(inode);
+	if (IS_ERR(inode))
+		goto out_free;
+
+	s->s_root = d_make_root(inode);
+	if (!s->s_root) {
+		rc = -ENOMEM;
+		goto out_free;
+	}
+
+	ecryptfs_set_dentry_lower(s->s_root, path.dentry);
+	ecryptfs_superblock_to_private(s)->lower_mnt = path.mnt;
+
+	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)
+		ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat);
+
+	printk(KERN_ERR "%s; rc = [%d]\n", err, rc);
+	return rc;
+}
+
+/**
+ * ecryptfs_kill_block_super
+ * @sb: The ecryptfs super block
+ *
+ * Used to bring the superblock down and free the private data.
+ */
+static void ecryptfs_kill_block_super(struct super_block *sb)
+{
+	struct ecryptfs_sb_info *sb_info = ecryptfs_superblock_to_private(sb);
+	kill_anon_super(sb);
+	if (!sb_info)
+		return;
+	mntput(sb_info->lower_mnt);
+	ecryptfs_destroy_mount_crypt_stat(&sb_info->mount_crypt_stat);
+	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_obj(struct ecryptfs_fs_context);
+	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",
+	.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
+ */
+static void
+inode_info_init_once(void *vptr)
+{
+	struct ecryptfs_inode_info *ei = (struct ecryptfs_inode_info *)vptr;
+
+	inode_init_once(&ei->vfs_inode);
+}
+
+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[] = {
+	{
+		.cache = &ecryptfs_auth_tok_list_item_cache,
+		.name = "ecryptfs_auth_tok_list_item",
+		.size = sizeof(struct ecryptfs_auth_tok_list_item),
+	},
+	{
+		.cache = &ecryptfs_file_info_cache,
+		.name = "ecryptfs_file_cache",
+		.size = sizeof(struct ecryptfs_file_info),
+	},
+	{
+		.cache = &ecryptfs_inode_info_cache,
+		.name = "ecryptfs_inode_cache",
+		.size = sizeof(struct ecryptfs_inode_info),
+		.flags = SLAB_ACCOUNT,
+		.ctor = inode_info_init_once,
+	},
+	{
+		.cache = &ecryptfs_sb_info_cache,
+		.name = "ecryptfs_sb_cache",
+		.size = sizeof(struct ecryptfs_sb_info),
+	},
+	{
+		.cache = &ecryptfs_header_cache,
+		.name = "ecryptfs_headers",
+		.size = PAGE_SIZE,
+	},
+	{
+		.cache = &ecryptfs_xattr_cache,
+		.name = "ecryptfs_xattr_cache",
+		.size = PAGE_SIZE,
+	},
+	{
+		.cache = &ecryptfs_key_record_cache,
+		.name = "ecryptfs_key_record_cache",
+		.size = sizeof(struct ecryptfs_key_record),
+	},
+	{
+		.cache = &ecryptfs_key_sig_cache,
+		.name = "ecryptfs_key_sig_cache",
+		.size = sizeof(struct ecryptfs_key_sig),
+	},
+	{
+		.cache = &ecryptfs_global_auth_tok_cache,
+		.name = "ecryptfs_global_auth_tok_cache",
+		.size = sizeof(struct ecryptfs_global_auth_tok),
+	},
+	{
+		.cache = &ecryptfs_key_tfm_cache,
+		.name = "ecryptfs_key_tfm_cache",
+		.size = sizeof(struct ecryptfs_key_tfm),
+	},
+};
+
+static void ecryptfs_free_kmem_caches(void)
+{
+	int i;
+
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+
+	for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+		struct ecryptfs_cache_info *info;
+
+		info = &ecryptfs_cache_infos[i];
+		kmem_cache_destroy(*(info->cache));
+	}
+}
+
+/**
+ * ecryptfs_init_kmem_caches
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_init_kmem_caches(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+		struct ecryptfs_cache_info *info;
+
+		info = &ecryptfs_cache_infos[i];
+		*(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: "
+					"kmem_cache_create failed\n",
+					info->name);
+			return -ENOMEM;
+		}
+	}
+	return 0;
+}
+
+static struct kobject *ecryptfs_kobj;
+
+static ssize_t version_show(struct kobject *kobj,
+			    struct kobj_attribute *attr, char *buff)
+{
+	return sysfs_emit(buff, "%d\n", ECRYPTFS_VERSIONING_MASK);
+}
+
+static struct kobj_attribute version_attr = __ATTR_RO(version);
+
+static struct attribute *attributes[] = {
+	&version_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group attr_group = {
+	.attrs = attributes,
+};
+
+static int do_sysfs_registration(void)
+{
+	int rc;
+
+	ecryptfs_kobj = kobject_create_and_add("ecryptfs", fs_kobj);
+	if (!ecryptfs_kobj) {
+		printk(KERN_ERR "Unable to create ecryptfs kset\n");
+		rc = -ENOMEM;
+		goto out;
+	}
+	rc = sysfs_create_group(ecryptfs_kobj, &attr_group);
+	if (rc) {
+		printk(KERN_ERR
+		       "Unable to create ecryptfs version attributes\n");
+		kobject_put(ecryptfs_kobj);
+	}
+out:
+	return rc;
+}
+
+static void do_sysfs_unregistration(void)
+{
+	sysfs_remove_group(ecryptfs_kobj, &attr_group);
+	kobject_put(ecryptfs_kobj);
+}
+
+static int __init ecryptfs_init(void)
+{
+	int rc;
+
+	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 "
+				"eCryptfs cannot run on this system. The "
+				"default eCryptfs extent size is [%u] bytes; "
+				"the page size is [%lu] bytes.\n",
+				ECRYPTFS_DEFAULT_EXTENT_SIZE,
+				(unsigned long)PAGE_SIZE);
+		goto out;
+	}
+	rc = ecryptfs_init_kmem_caches();
+	if (rc) {
+		printk(KERN_ERR
+		       "Failed to allocate one or more kmem_cache objects\n");
+		goto out;
+	}
+	rc = do_sysfs_registration();
+	if (rc) {
+		printk(KERN_ERR "sysfs registration failed\n");
+		goto out_free_kmem_caches;
+	}
+	rc = ecryptfs_init_kthread();
+	if (rc) {
+		printk(KERN_ERR "%s: kthread initialization failed; "
+		       "rc = [%d]\n", __func__, rc);
+		goto out_do_sysfs_unregistration;
+	}
+	rc = ecryptfs_init_messaging();
+	if (rc) {
+		printk(KERN_ERR "Failure occurred while attempting to "
+				"initialize the communications channel to "
+				"ecryptfsd\n");
+		goto out_destroy_kthread;
+	}
+	rc = ecryptfs_init_crypto();
+	if (rc) {
+		printk(KERN_ERR "Failure whilst attempting to init crypto; "
+		       "rc = [%d]\n", rc);
+		goto out_release_messaging;
+	}
+	rc = register_filesystem(&ecryptfs_fs_type);
+	if (rc) {
+		printk(KERN_ERR "Failed to register filesystem\n");
+		goto out_destroy_crypto;
+	}
+	if (ecryptfs_verbosity > 0)
+		printk(KERN_CRIT "eCryptfs verbosity set to %d. Secret values "
+			"will be written to the syslog!\n", ecryptfs_verbosity);
+
+	goto out;
+out_destroy_crypto:
+	ecryptfs_destroy_crypto();
+out_release_messaging:
+	ecryptfs_release_messaging();
+out_destroy_kthread:
+	ecryptfs_destroy_kthread();
+out_do_sysfs_unregistration:
+	do_sysfs_unregistration();
+out_free_kmem_caches:
+	ecryptfs_free_kmem_caches();
+out:
+	return rc;
+}
+
+static void __exit ecryptfs_exit(void)
+{
+	int rc;
+
+	rc = ecryptfs_destroy_crypto();
+	if (rc)
+		printk(KERN_ERR "Failure whilst attempting to destroy crypto; "
+		       "rc = [%d]\n", rc);
+	ecryptfs_release_messaging();
+	ecryptfs_destroy_kthread();
+	do_sysfs_unregistration();
+	unregister_filesystem(&ecryptfs_fs_type);
+	ecryptfs_free_kmem_caches();
+}
+
+MODULE_AUTHOR("Michael A. Halcrow <mhalcrow@us.ibm.com>");
+MODULE_DESCRIPTION("eCryptfs");
+
+MODULE_LICENSE("GPL");
+
+module_init(ecryptfs_init)
+module_exit(ecryptfs_exit)