Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Says Tyler:
 "Tim's logging message update will be really helpful to users when
  they're trying to locate a problematic file in the lower filesystem
  with filename encryption enabled.

  You'll recognize the fix from Li, as you commented on that.

  You should also be familiar with my setattr/truncate improvements,
  since you were the one that pointed them out to us (thanks again!).
  Andrew noted the /dev/ecryptfs write count sanitization needed to be
  improved, so I've got a fix in there for that along with some other
  less important cleanups of the /dev/ecryptfs read/write code."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  eCryptfs: Fix oops when printing debug info in extent crypto functions
  eCryptfs: Remove unused ecryptfs_read()
  eCryptfs: Check inode changes in setattr
  eCryptfs: Make truncate path killable
  eCryptfs: Infinite loop due to overflow in ecryptfs_write()
  eCryptfs: Replace miscdev read/write magic numbers
  eCryptfs: Report errors in writes to /dev/ecryptfs
  eCryptfs: Sanitize write counts of /dev/ecryptfs
  ecryptfs: Remove unnecessary variable initialization
  ecryptfs: Improve metadata read failure logging
  MAINTAINERS: Update eCryptfs maintainer address

MAINTAINERS

@@ -2402,7 +2402,7 @@ F:	net/bridge/netfilter/ebt*.c
 
 ECRYPT FILE SYSTEM
 M:	Tyler Hicks <tyhicks@canonical.com>
-M:	Dustin Kirkland <kirkland@canonical.com>
+M:	Dustin Kirkland <dustin.kirkland@gazzang.com>
 L:	ecryptfs@vger.kernel.org
 W:	https://launchpad.net/ecryptfs
 S:	Supported

fs/ecryptfs/crypto.c

@@ -417,17 +417,6 @@ static int ecryptfs_encrypt_extent(struct page *enc_extent_page,
 			(unsigned long long)(extent_base + extent_offset), rc);
 		goto out;
 	}
-	if (unlikely(ecryptfs_verbosity > 0)) {
-		ecryptfs_printk(KERN_DEBUG, "Encrypting extent "
-				"with iv:\n");
-		ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
-		ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
-				"encryption:\n");
-		ecryptfs_dump_hex((char *)
-				  (page_address(page)
-				   + (extent_offset * crypt_stat->extent_size)),
-				  8);
-	}
 	rc = ecryptfs_encrypt_page_offset(crypt_stat, enc_extent_page, 0,
 					  page, (extent_offset
 						 * crypt_stat->extent_size),
@@ -440,14 +429,6 @@ static int ecryptfs_encrypt_extent(struct page *enc_extent_page,
 		goto out;
 	}
 	rc = 0;
-	if (unlikely(ecryptfs_verbosity > 0)) {
-		ecryptfs_printk(KERN_DEBUG, "Encrypt extent [0x%.16llx]; "
-			"rc = [%d]\n",
-			(unsigned long long)(extent_base + extent_offset), rc);
-		ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
-				"encryption:\n");
-		ecryptfs_dump_hex((char *)(page_address(enc_extent_page)), 8);
-	}
 out:
 	return rc;
 }
@@ -543,17 +524,6 @@ static int ecryptfs_decrypt_extent(struct page *page,
 			(unsigned long long)(extent_base + extent_offset), rc);
 		goto out;
 	}
-	if (unlikely(ecryptfs_verbosity > 0)) {
-		ecryptfs_printk(KERN_DEBUG, "Decrypting extent "
-				"with iv:\n");
-		ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
-		ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
-				"decryption:\n");
-		ecryptfs_dump_hex((char *)
-				  (page_address(enc_extent_page)
-				   + (extent_offset * crypt_stat->extent_size)),
-				  8);
-	}
 	rc = ecryptfs_decrypt_page_offset(crypt_stat, page,
 					  (extent_offset
 					   * crypt_stat->extent_size),
@@ -567,16 +537,6 @@ static int ecryptfs_decrypt_extent(struct page *page,
 		goto out;
 	}
 	rc = 0;
-	if (unlikely(ecryptfs_verbosity > 0)) {
-		ecryptfs_printk(KERN_DEBUG, "Decrypt extent [0x%.16llx]; "
-			"rc = [%d]\n",
-			(unsigned long long)(extent_base + extent_offset), rc);
-		ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
-				"decryption:\n");
-		ecryptfs_dump_hex((char *)(page_address(page)
-					   + (extent_offset
-					      * crypt_stat->extent_size)), 8);
-	}
 out:
 	return rc;
 }
@@ -1590,8 +1550,8 @@ int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
  */
 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 {
-	int rc = 0;
-	char *page_virt = NULL;
+	int rc;
+	char *page_virt;
 	struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
 	struct ecryptfs_crypt_stat *crypt_stat =
 	    &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
@@ -1616,11 +1576,13 @@ int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 						ecryptfs_dentry,
 						ECRYPTFS_VALIDATE_HEADER_SIZE);
 	if (rc) {
+		/* metadata is not in the file header, so try xattrs */
 		memset(page_virt, 0, PAGE_CACHE_SIZE);
 		rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_inode);
 		if (rc) {
 			printk(KERN_DEBUG "Valid eCryptfs headers not found in "
-			       "file header region or xattr region\n");
+			       "file header region or xattr region, inode %lu\n",
+				ecryptfs_inode->i_ino);
 			rc = -EINVAL;
 			goto out;
 		}
@@ -1629,7 +1591,8 @@ int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 						ECRYPTFS_DONT_VALIDATE_HEADER_SIZE);
 		if (rc) {
 			printk(KERN_DEBUG "Valid eCryptfs headers not found in "
-			       "file xattr region either\n");
+			       "file xattr region either, inode %lu\n",
+				ecryptfs_inode->i_ino);
 			rc = -EINVAL;
 		}
 		if (crypt_stat->mount_crypt_stat->flags
@@ -1640,7 +1603,8 @@ int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 			       "crypto metadata only in the extended attribute "
 			       "region, but eCryptfs was mounted without "
 			       "xattr support enabled. eCryptfs will not treat "
-			       "this like an encrypted file.\n");
+			       "this like an encrypted file, inode %lu\n",
+				ecryptfs_inode->i_ino);
 			rc = -EINVAL;
 		}
 	}

fs/ecryptfs/ecryptfs_kernel.h

@@ -151,6 +151,11 @@ ecryptfs_get_key_payload_data(struct key *key)
 					  * dentry name */
 #define ECRYPTFS_TAG_73_PACKET_TYPE 0x49 /* FEK-encrypted filename as
 					  * metadata */
+#define ECRYPTFS_MIN_PKT_LEN_SIZE 1 /* Min size to specify packet length */
+#define ECRYPTFS_MAX_PKT_LEN_SIZE 2 /* Pass at least this many bytes to
+				     * ecryptfs_parse_packet_length() and
+				     * ecryptfs_write_packet_length()
+				     */
 /* Constraint: ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES >=
  * ECRYPTFS_MAX_IV_BYTES */
 #define ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES 16

fs/ecryptfs/inode.c

@@ -822,18 +822,6 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 		size_t num_zeros = (PAGE_CACHE_SIZE
 				    - (ia->ia_size & ~PAGE_CACHE_MASK));
 
-
-		/*
-		 * XXX(truncate) this should really happen at the begginning
-		 * of ->setattr.  But the code is too messy to that as part
-		 * of a larger patch.  ecryptfs is also totally missing out
-		 * on the inode_change_ok check at the beginning of
-		 * ->setattr while would include this.
-		 */
-		rc = inode_newsize_ok(inode, ia->ia_size);
-		if (rc)
-			goto out;
-
 		if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
 			truncate_setsize(inode, ia->ia_size);
 			lower_ia->ia_size = ia->ia_size;
@@ -883,6 +871,28 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 	return rc;
 }
 
+static int ecryptfs_inode_newsize_ok(struct inode *inode, loff_t offset)
+{
+	struct ecryptfs_crypt_stat *crypt_stat;
+	loff_t lower_oldsize, lower_newsize;
+
+	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+	lower_oldsize = upper_size_to_lower_size(crypt_stat,
+						 i_size_read(inode));
+	lower_newsize = upper_size_to_lower_size(crypt_stat, offset);
+	if (lower_newsize > lower_oldsize) {
+		/*
+		 * The eCryptfs inode and the new *lower* size are mixed here
+		 * because we may not have the lower i_mutex held and/or it may
+		 * not be appropriate to call inode_newsize_ok() with inodes
+		 * from other filesystems.
+		 */
+		return inode_newsize_ok(inode, lower_newsize);
+	}
+
+	return 0;
+}
+
 /**
  * ecryptfs_truncate
  * @dentry: The ecryptfs layer dentry
@@ -899,6 +909,10 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
 	struct iattr lower_ia = { .ia_valid = 0 };
 	int rc;
 
+	rc = ecryptfs_inode_newsize_ok(dentry->d_inode, new_length);
+	if (rc)
+		return rc;
+
 	rc = truncate_upper(dentry, &ia, &lower_ia);
 	if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
 		struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
@@ -978,6 +992,16 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
 		}
 	}
 	mutex_unlock(&crypt_stat->cs_mutex);
+
+	rc = inode_change_ok(inode, ia);
+	if (rc)
+		goto out;
+	if (ia->ia_valid & ATTR_SIZE) {
+		rc = ecryptfs_inode_newsize_ok(inode, ia->ia_size);
+		if (rc)
+			goto out;
+	}
+
 	if (S_ISREG(inode->i_mode)) {
 		rc = filemap_write_and_wait(inode->i_mapping);
 		if (rc)

fs/ecryptfs/keystore.c

@@ -109,7 +109,7 @@ int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
 		(*size) += ((unsigned char)(data[1]) + 192);
 		(*length_size) = 2;
 	} else if (data[0] == 255) {
-		/* Five-byte length; we're not supposed to see this */
+		/* If support is added, adjust ECRYPTFS_MAX_PKT_LEN_SIZE */
 		ecryptfs_printk(KERN_ERR, "Five-byte packet length not "
 				"supported\n");
 		rc = -EINVAL;
@@ -126,7 +126,7 @@ int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
 /**
  * ecryptfs_write_packet_length
  * @dest: The byte array target into which to write the length. Must
- *        have at least 5 bytes allocated.
+ *        have at least ECRYPTFS_MAX_PKT_LEN_SIZE bytes allocated.
  * @size: The length to write.
  * @packet_size_length: The number of bytes used to encode the packet
  *                      length is written to this address.
@@ -146,6 +146,7 @@ int ecryptfs_write_packet_length(char *dest, size_t size,
 		dest[1] = ((size - 192) % 256);
 		(*packet_size_length) = 2;
 	} else {
+		/* If support is added, adjust ECRYPTFS_MAX_PKT_LEN_SIZE */
 		rc = -EINVAL;
 		ecryptfs_printk(KERN_WARNING,
 				"Unsupported packet size: [%zd]\n", size);

fs/ecryptfs/miscdev.c

@@ -218,6 +218,29 @@ int ecryptfs_send_miscdev(char *data, size_t data_size,
 	return rc;
 }
 
+/*
+ * miscdevfs packet format:
+ *  Octet 0: Type
+ *  Octets 1-4: network byte order msg_ctx->counter
+ *  Octets 5-N0: Size of struct ecryptfs_message to follow
+ *  Octets N0-N1: struct ecryptfs_message (including data)
+ *
+ *  Octets 5-N1 not written if the packet type does not include a message
+ */
+#define PKT_TYPE_SIZE		1
+#define PKT_CTR_SIZE		4
+#define MIN_NON_MSG_PKT_SIZE	(PKT_TYPE_SIZE + PKT_CTR_SIZE)
+#define MIN_MSG_PKT_SIZE	(PKT_TYPE_SIZE + PKT_CTR_SIZE \
+				 + ECRYPTFS_MIN_PKT_LEN_SIZE)
+/* 4 + ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES comes from tag 65 packet format */
+#define MAX_MSG_PKT_SIZE	(PKT_TYPE_SIZE + PKT_CTR_SIZE \
+				 + ECRYPTFS_MAX_PKT_LEN_SIZE \
+				 + sizeof(struct ecryptfs_message) \
+				 + 4 + ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES)
+#define PKT_TYPE_OFFSET		0
+#define PKT_CTR_OFFSET		PKT_TYPE_SIZE
+#define PKT_LEN_OFFSET		(PKT_TYPE_SIZE + PKT_CTR_SIZE)
+
 /**
  * ecryptfs_miscdev_read - format and send message from queue
  * @file: fs/ecryptfs/euid miscdevfs handle (ignored)
@@ -237,7 +260,7 @@ ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count,
 	struct ecryptfs_daemon *daemon;
 	struct ecryptfs_msg_ctx *msg_ctx;
 	size_t packet_length_size;
-	char packet_length[3];
+	char packet_length[ECRYPTFS_MAX_PKT_LEN_SIZE];
 	size_t i;
 	size_t total_length;
 	uid_t euid = current_euid();
@@ -305,15 +328,8 @@ ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count,
 		packet_length_size = 0;
 		msg_ctx->msg_size = 0;
 	}
-	/* miscdevfs packet format:
-	 *  Octet 0: Type
-	 *  Octets 1-4: network byte order msg_ctx->counter
-	 *  Octets 5-N0: Size of struct ecryptfs_message to follow
-	 *  Octets N0-N1: struct ecryptfs_message (including data)
-	 *
-	 *  Octets 5-N1 not written if the packet type does not
-	 *  include a message */
-	total_length = (1 + 4 + packet_length_size + msg_ctx->msg_size);
+	total_length = (PKT_TYPE_SIZE + PKT_CTR_SIZE + packet_length_size
+			+ msg_ctx->msg_size);
 	if (count < total_length) {
 		rc = 0;
 		printk(KERN_WARNING "%s: Only given user buffer of "
@@ -324,9 +340,10 @@ ecryptfs_miscdev_read(struct file *file, char __user *buf, size_t count,
 	rc = -EFAULT;
 	if (put_user(msg_ctx->type, buf))
 		goto out_unlock_msg_ctx;
-	if (put_user(cpu_to_be32(msg_ctx->counter), (__be32 __user *)(buf + 1)))
+	if (put_user(cpu_to_be32(msg_ctx->counter),
+		     (__be32 __user *)(&buf[PKT_CTR_OFFSET])))
 		goto out_unlock_msg_ctx;
-	i = 5;
+	i = PKT_TYPE_SIZE + PKT_CTR_SIZE;
 	if (msg_ctx->msg) {
 		if (copy_to_user(&buf[i], packet_length, packet_length_size))
 			goto out_unlock_msg_ctx;
@@ -391,12 +408,6 @@ static int ecryptfs_miscdev_response(char *data, size_t data_size,
  * @count: Amount of data in @buf
  * @ppos: Pointer to offset in file (ignored)
  *
- * miscdevfs packet format:
- *  Octet 0: Type
- *  Octets 1-4: network byte order msg_ctx->counter (0's for non-response)
- *  Octets 5-N0: Size of struct ecryptfs_message to follow
- *  Octets N0-N1: struct ecryptfs_message (including data)
- *
  * Returns the number of bytes read from @buf
  */
 static ssize_t
@@ -405,60 +416,78 @@ ecryptfs_miscdev_write(struct file *file, const char __user *buf,
 {
 	__be32 counter_nbo;
 	u32 seq;
-	size_t packet_size, packet_size_length, i;
-	ssize_t sz = 0;
+	size_t packet_size, packet_size_length;
 	char *data;
 	uid_t euid = current_euid();
-	int rc;
+	unsigned char packet_size_peek[ECRYPTFS_MAX_PKT_LEN_SIZE];
+	ssize_t rc;
 
-	if (count == 0)
-		goto out;
+	if (count == 0) {
+		return 0;
+	} else if (count == MIN_NON_MSG_PKT_SIZE) {
+		/* Likely a harmless MSG_HELO or MSG_QUIT - no packet length */
+		goto memdup;
+	} else if (count < MIN_MSG_PKT_SIZE || count > MAX_MSG_PKT_SIZE) {
+		printk(KERN_WARNING "%s: Acceptable packet size range is "
+		       "[%d-%lu], but amount of data written is [%zu].",
+		       __func__, MIN_MSG_PKT_SIZE, MAX_MSG_PKT_SIZE, count);
+		return -EINVAL;
+	}
+
+	if (copy_from_user(packet_size_peek, &buf[PKT_LEN_OFFSET],
+			   sizeof(packet_size_peek))) {
+		printk(KERN_WARNING "%s: Error while inspecting packet size\n",
+		       __func__);
+		return -EFAULT;
+	}
 
+	rc = ecryptfs_parse_packet_length(packet_size_peek, &packet_size,
+					  &packet_size_length);
+	if (rc) {
+		printk(KERN_WARNING "%s: Error parsing packet length; "
+		       "rc = [%zd]\n", __func__, rc);
+		return rc;
+	}
+
+	if ((PKT_TYPE_SIZE + PKT_CTR_SIZE + packet_size_length + packet_size)
+	    != count) {
+		printk(KERN_WARNING "%s: Invalid packet size [%zu]\n", __func__,
+		       packet_size);
+		return -EINVAL;
+	}
+
+memdup:
 	data = memdup_user(buf, count);
 	if (IS_ERR(data)) {
 		printk(KERN_ERR "%s: memdup_user returned error [%ld]\n",
 		       __func__, PTR_ERR(data));
-		goto out;
+		return PTR_ERR(data);
 	}
-	sz = count;
-	i = 0;
-	switch (data[i++]) {
+	switch (data[PKT_TYPE_OFFSET]) {
 	case ECRYPTFS_MSG_RESPONSE:
-		if (count < (1 + 4 + 1 + sizeof(struct ecryptfs_message))) {
+		if (count < (MIN_MSG_PKT_SIZE
+			     + sizeof(struct ecryptfs_message))) {
 			printk(KERN_WARNING "%s: Minimum acceptable packet "
 			       "size is [%zd], but amount of data written is "
 			       "only [%zd]. Discarding response packet.\n",
 			       __func__,
-			       (1 + 4 + 1 + sizeof(struct ecryptfs_message)),
-			       count);
+			       (MIN_MSG_PKT_SIZE
+				+ sizeof(struct ecryptfs_message)), count);
+			rc = -EINVAL;
 			goto out_free;
 		}
-		memcpy(&counter_nbo, &data[i], 4);
+		memcpy(&counter_nbo, &data[PKT_CTR_OFFSET], PKT_CTR_SIZE);
 		seq = be32_to_cpu(counter_nbo);
-		i += 4;
-		rc = ecryptfs_parse_packet_length(&data[i], &packet_size,
-						  &packet_size_length);
+		rc = ecryptfs_miscdev_response(
+				&data[PKT_LEN_OFFSET + packet_size_length],
+				packet_size, euid, current_user_ns(),
+				task_pid(current), seq);
 		if (rc) {
-			printk(KERN_WARNING "%s: Error parsing packet length; "
-			       "rc = [%d]\n", __func__, rc);
-			goto out_free;
-		}
-		i += packet_size_length;
-		if ((1 + 4 + packet_size_length + packet_size) != count) {
-			printk(KERN_WARNING "%s: (1 + packet_size_length([%zd])"
-			       " + packet_size([%zd]))([%zd]) != "
-			       "count([%zd]). Invalid packet format.\n",
-			       __func__, packet_size_length, packet_size,
-			       (1 + packet_size_length + packet_size), count);
-			goto out_free;
-		}
-		rc = ecryptfs_miscdev_response(&data[i], packet_size,
-					       euid, current_user_ns(),
-					       task_pid(current), seq);
-		if (rc)
 			printk(KERN_WARNING "%s: Failed to deliver miscdev "
-			       "response to requesting operation; rc = [%d]\n",
+			       "response to requesting operation; rc = [%zd]\n",
 			       __func__, rc);
+			goto out_free;
+		}
 		break;
 	case ECRYPTFS_MSG_HELO:
 	case ECRYPTFS_MSG_QUIT:
@@ -467,12 +496,13 @@ ecryptfs_miscdev_write(struct file *file, const char __user *buf,
 		ecryptfs_printk(KERN_WARNING, "Dropping miscdev "
 				"message of unrecognized type [%d]\n",
 				data[0]);
-		break;
+		rc = -EINVAL;
+		goto out_free;
 	}
+	rc = count;
 out_free:
 	kfree(data);
-out:
-	return sz;
+	return rc;
 }
 
 

fs/ecryptfs/read_write.c

@@ -130,13 +130,18 @@ int ecryptfs_write(struct inode *ecryptfs_inode, char *data, loff_t offset,
 		pgoff_t ecryptfs_page_idx = (pos >> PAGE_CACHE_SHIFT);
 		size_t start_offset_in_page = (pos & ~PAGE_CACHE_MASK);
 		size_t num_bytes = (PAGE_CACHE_SIZE - start_offset_in_page);
-		size_t total_remaining_bytes = ((offset + size) - pos);
+		loff_t total_remaining_bytes = ((offset + size) - pos);
+
+		if (fatal_signal_pending(current)) {
+			rc = -EINTR;
+			break;
+		}
 
 		if (num_bytes > total_remaining_bytes)
 			num_bytes = total_remaining_bytes;
 		if (pos < offset) {
 			/* remaining zeros to write, up to destination offset */
-			size_t total_remaining_zeros = (offset - pos);
+			loff_t total_remaining_zeros = (offset - pos);
 
 			if (num_bytes > total_remaining_zeros)
 				num_bytes = total_remaining_zeros;
@@ -193,15 +198,19 @@ int ecryptfs_write(struct inode *ecryptfs_inode, char *data, loff_t offset,
 		}
 		pos += num_bytes;
 	}
-	if ((offset + size) > ecryptfs_file_size) {
-		i_size_write(ecryptfs_inode, (offset + size));
+	if (pos > ecryptfs_file_size) {
+		i_size_write(ecryptfs_inode, pos);
 		if (crypt_stat->flags & ECRYPTFS_ENCRYPTED) {
-			rc = ecryptfs_write_inode_size_to_metadata(
+			int rc2;
+
+			rc2 = ecryptfs_write_inode_size_to_metadata(
 								ecryptfs_inode);
-			if (rc) {
+			if (rc2) {
 				printk(KERN_ERR	"Problem with "
 				       "ecryptfs_write_inode_size_to_metadata; "
-				       "rc = [%d]\n", rc);
+				       "rc = [%d]\n", rc2);
+				if (!rc)
+					rc = rc2;
 				goto out;
 			}
 		}
@@ -273,76 +282,3 @@ int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
 	flush_dcache_page(page_for_ecryptfs);
 	return rc;
 }
-
-#if 0
-/**
- * ecryptfs_read
- * @data: The virtual address into which to write the data read (and
- *        possibly decrypted) from the lower file
- * @offset: The offset in the decrypted view of the file from which to
- *          read into @data
- * @size: The number of bytes to read into @data
- * @ecryptfs_file: The eCryptfs file from which to read
- *
- * Read an arbitrary amount of data from an arbitrary location in the
- * eCryptfs page cache. This is done on an extent-by-extent basis;
- * individual extents are decrypted and read from the lower page
- * cache (via VFS reads). This function takes care of all the
- * address translation to locations in the lower filesystem.
- *
- * Returns zero on success; non-zero otherwise
- */
-int ecryptfs_read(char *data, loff_t offset, size_t size,
-		  struct file *ecryptfs_file)
-{
-	struct inode *ecryptfs_inode = ecryptfs_file->f_dentry->d_inode;
-	struct page *ecryptfs_page;
-	char *ecryptfs_page_virt;
-	loff_t ecryptfs_file_size = i_size_read(ecryptfs_inode);
-	loff_t data_offset = 0;
-	loff_t pos;
-	int rc = 0;
-
-	if ((offset + size) > ecryptfs_file_size) {
-		rc = -EINVAL;
-		printk(KERN_ERR "%s: Attempt to read data past the end of the "
-			"file; offset = [%lld]; size = [%td]; "
-		       "ecryptfs_file_size = [%lld]\n",
-		       __func__, offset, size, ecryptfs_file_size);
-		goto out;
-	}
-	pos = offset;
-	while (pos < (offset + size)) {
-		pgoff_t ecryptfs_page_idx = (pos >> PAGE_CACHE_SHIFT);
-		size_t start_offset_in_page = (pos & ~PAGE_CACHE_MASK);
-		size_t num_bytes = (PAGE_CACHE_SIZE - start_offset_in_page);
-		size_t total_remaining_bytes = ((offset + size) - pos);
-
-		if (num_bytes > total_remaining_bytes)
-			num_bytes = total_remaining_bytes;
-		ecryptfs_page = ecryptfs_get_locked_page(ecryptfs_inode,
-							 ecryptfs_page_idx);
-		if (IS_ERR(ecryptfs_page)) {
-			rc = PTR_ERR(ecryptfs_page);
-			printk(KERN_ERR "%s: Error getting page at "
-			       "index [%ld] from eCryptfs inode "
-			       "mapping; rc = [%d]\n", __func__,
-			       ecryptfs_page_idx, rc);
-			goto out;
-		}
-		ecryptfs_page_virt = kmap_atomic(ecryptfs_page, KM_USER0);
-		memcpy((data + data_offset),
-		       ((char *)ecryptfs_page_virt + start_offset_in_page),
-		       num_bytes);
-		kunmap_atomic(ecryptfs_page_virt, KM_USER0);
-		flush_dcache_page(ecryptfs_page);
-		SetPageUptodate(ecryptfs_page);
-		unlock_page(ecryptfs_page);
-		page_cache_release(ecryptfs_page);
-		pos += num_bytes;
-		data_offset += num_bytes;
-	}
-out:
-	return rc;
-}
-#endif  /*  0  */