1 files changed, 184 insertions, 117 deletions

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 4a430ab4115..3fbc9420338 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -31,6 +31,7 @@
 #include <linux/mount.h>
 #include <linux/crypto.h>
 #include <linux/fs_stack.h>
+#include <linux/slab.h>
 #include <asm/unaligned.h>
 #include "ecryptfs_kernel.h"
 
@@ -141,19 +142,10 @@ out:
 static int grow_file(struct dentry *ecryptfs_dentry)
 {
 	struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
-	struct file fake_file;
-	struct ecryptfs_file_info tmp_file_info;
 	char zero_virt[] = { 0x00 };
 	int rc = 0;
 
-	memset(&fake_file, 0, sizeof(fake_file));
-	fake_file.f_path.dentry = ecryptfs_dentry;
-	memset(&tmp_file_info, 0, sizeof(tmp_file_info));
-	ecryptfs_set_file_private(&fake_file, &tmp_file_info);
-	ecryptfs_set_file_lower(
-		&fake_file,
-		ecryptfs_inode_to_private(ecryptfs_inode)->lower_file);
-	rc = ecryptfs_write(&fake_file, zero_virt, 0, 1);
+	rc = ecryptfs_write(ecryptfs_inode, zero_virt, 0, 1);
 	i_size_write(ecryptfs_inode, 0);
 	rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
 	ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |=
@@ -272,7 +264,7 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
 		printk(KERN_ERR "%s: Out of memory whilst attempting "
 		       "to allocate ecryptfs_dentry_info struct\n",
 			__func__);
-		goto out_dput;
+		goto out_put;
 	}
 	ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
 	ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
@@ -323,6 +315,7 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
 	rc = ecryptfs_read_and_validate_header_region(page_virt,
 						      ecryptfs_dentry->d_inode);
 	if (rc) {
+		memset(page_virt, 0, PAGE_CACHE_SIZE);
 		rc = ecryptfs_read_and_validate_xattr_region(page_virt,
 							     ecryptfs_dentry);
 		if (rc) {
@@ -335,7 +328,7 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
 		ecryptfs_dentry->d_sb)->mount_crypt_stat;
 	if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
 		if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
-			file_size = (crypt_stat->num_header_bytes_at_front
+			file_size = (crypt_stat->metadata_size
 				     + i_size_read(lower_dentry->d_inode));
 		else
 			file_size = i_size_read(lower_dentry->d_inode);
@@ -346,14 +339,84 @@ int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
 out_free_kmem:
 	kmem_cache_free(ecryptfs_header_cache_2, page_virt);
 	goto out;
-out_dput:
+out_put:
 	dput(lower_dentry);
+	mntput(lower_mnt);
 	d_drop(ecryptfs_dentry);
 out:
 	return rc;
 }
 
 /**
+ * ecryptfs_new_lower_dentry
+ * @name: The name of the new dentry.
+ * @lower_dir_dentry: Parent directory of the new dentry.
+ * @nd: nameidata from last lookup.
+ *
+ * Create a new dentry or get it from lower parent dir.
+ */
+static struct dentry *
+ecryptfs_new_lower_dentry(struct qstr *name, struct dentry *lower_dir_dentry,
+			  struct nameidata *nd)
+{
+	struct dentry *new_dentry;
+	struct dentry *tmp;
+	struct inode *lower_dir_inode;
+
+	lower_dir_inode = lower_dir_dentry->d_inode;
+
+	tmp = d_alloc(lower_dir_dentry, name);
+	if (!tmp)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_lock(&lower_dir_inode->i_mutex);
+	new_dentry = lower_dir_inode->i_op->lookup(lower_dir_inode, tmp, nd);
+	mutex_unlock(&lower_dir_inode->i_mutex);
+
+	if (!new_dentry)
+		new_dentry = tmp;
+	else
+		dput(tmp);
+
+	return new_dentry;
+}
+
+
+/**
+ * ecryptfs_lookup_one_lower
+ * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
+ * @lower_dir_dentry: lower parent directory
+ * @name: lower file name
+ *
+ * Get the lower dentry from vfs. If lower dentry does not exist yet,
+ * create it.
+ */
+static struct dentry *
+ecryptfs_lookup_one_lower(struct dentry *ecryptfs_dentry,
+			  struct dentry *lower_dir_dentry, struct qstr *name)
+{
+	struct nameidata nd;
+	struct vfsmount *lower_mnt;
+	int err;
+
+	lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
+				    ecryptfs_dentry->d_parent));
+	err = vfs_path_lookup(lower_dir_dentry, lower_mnt, name->name , 0, &nd);
+	mntput(lower_mnt);
+
+	if (!err) {
+		/* we dont need the mount */
+		mntput(nd.path.mnt);
+		return nd.path.dentry;
+	}
+	if (err != -ENOENT)
+		return ERR_PTR(err);
+
+	/* create a new lower dentry */
+	return ecryptfs_new_lower_dentry(name, lower_dir_dentry, &nd);
+}
+
+/**
  * ecryptfs_lookup
  * @ecryptfs_dir_inode: The eCryptfs directory inode
  * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
@@ -370,6 +433,7 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
 	size_t encrypted_and_encoded_name_size;
 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 	struct dentry *lower_dir_dentry, *lower_dentry;
+	struct qstr lower_name;
 	int rc = 0;
 
 	ecryptfs_dentry->d_op = &ecryptfs_dops;
@@ -380,16 +444,22 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
 		goto out_d_drop;
 	}
 	lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
-	mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
-	lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name,
-				      lower_dir_dentry,
-				      ecryptfs_dentry->d_name.len);
-	mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
+	lower_name.name = ecryptfs_dentry->d_name.name;
+	lower_name.len = ecryptfs_dentry->d_name.len;
+	lower_name.hash = ecryptfs_dentry->d_name.hash;
+	if (lower_dir_dentry->d_op && lower_dir_dentry->d_op->d_hash) {
+		rc = lower_dir_dentry->d_op->d_hash(lower_dir_dentry,
+						    &lower_name);
+		if (rc < 0)
+			goto out_d_drop;
+	}
+	lower_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
+						 lower_dir_dentry, &lower_name);
 	if (IS_ERR(lower_dentry)) {
 		rc = PTR_ERR(lower_dentry);
-		printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "
-		       "lower_dentry = [%s]\n", __func__, rc,
-		       ecryptfs_dentry->d_name.name);
+		ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_lower() returned "
+				"[%d] on lower_dentry = [%s]\n", __func__, rc,
+				encrypted_and_encoded_name);
 		goto out_d_drop;
 	}
 	if (lower_dentry->d_inode)
@@ -409,16 +479,22 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
 		       "filename; rc = [%d]\n", __func__, rc);
 		goto out_d_drop;
 	}
-	mutex_lock(&lower_dir_dentry->d_inode->i_mutex);
-	lower_dentry = lookup_one_len(encrypted_and_encoded_name,
-				      lower_dir_dentry,
-				      encrypted_and_encoded_name_size - 1);
-	mutex_unlock(&lower_dir_dentry->d_inode->i_mutex);
+	lower_name.name = encrypted_and_encoded_name;
+	lower_name.len = encrypted_and_encoded_name_size;
+	lower_name.hash = full_name_hash(lower_name.name, lower_name.len);
+	if (lower_dir_dentry->d_op && lower_dir_dentry->d_op->d_hash) {
+		rc = lower_dir_dentry->d_op->d_hash(lower_dir_dentry,
+						    &lower_name);
+		if (rc < 0)
+			goto out_d_drop;
+	}
+	lower_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
+						 lower_dir_dentry, &lower_name);
 	if (IS_ERR(lower_dentry)) {
 		rc = PTR_ERR(lower_dentry);
-		printk(KERN_ERR "%s: lookup_one_len() returned [%d] on "
-		       "lower_dentry = [%s]\n", __func__, rc,
-		       encrypted_and_encoded_name);
+		ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_lower() returned "
+				"[%d] on lower_dentry = [%s]\n", __func__, rc,
+				encrypted_and_encoded_name);
 		goto out_d_drop;
 	}
 lookup_and_interpose:
@@ -455,8 +531,8 @@ static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
 	rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
 	if (rc)
 		goto out_lock;
-	fsstack_copy_attr_times(dir, lower_new_dentry->d_inode);
-	fsstack_copy_inode_size(dir, lower_new_dentry->d_inode);
+	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
+	fsstack_copy_inode_size(dir, lower_dir_dentry->d_inode);
 	old_dentry->d_inode->i_nlink =
 		ecryptfs_inode_to_lower(old_dentry->d_inode)->i_nlink;
 	i_size_write(new_dentry->d_inode, file_size_save);
@@ -647,38 +723,17 @@ out_lock:
 	return rc;
 }
 
-static int
-ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
+static int ecryptfs_readlink_lower(struct dentry *dentry, char **buf,
+				   size_t *bufsiz)
 {
+	struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	char *lower_buf;
-	size_t lower_bufsiz;
-	struct dentry *lower_dentry;
-	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
-	char *plaintext_name;
-	size_t plaintext_name_size;
+	size_t lower_bufsiz = PATH_MAX;
 	mm_segment_t old_fs;
 	int rc;
 
-	lower_dentry = ecryptfs_dentry_to_lower(dentry);
-	if (!lower_dentry->d_inode->i_op->readlink) {
-		rc = -EINVAL;
-		goto out;
-	}
-	mount_crypt_stat = &ecryptfs_superblock_to_private(
-						dentry->d_sb)->mount_crypt_stat;
-	/*
-	 * If the lower filename is encrypted, it will result in a significantly
-	 * longer name.  If needed, truncate the name after decode and decrypt.
-	 */
-	if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
-		lower_bufsiz = PATH_MAX;
-	else
-		lower_bufsiz = bufsiz;
-	/* Released in this function */
 	lower_buf = kmalloc(lower_bufsiz, GFP_KERNEL);
-	if (lower_buf == NULL) {
-		printk(KERN_ERR "%s: Out of memory whilst attempting to "
-		       "kmalloc [%zd] bytes\n", __func__, lower_bufsiz);
+	if (!lower_buf) {
 		rc = -ENOMEM;
 		goto out;
 	}
@@ -688,29 +743,31 @@ ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
 						   (char __user *)lower_buf,
 						   lower_bufsiz);
 	set_fs(old_fs);
-	if (rc >= 0) {
-		rc = ecryptfs_decode_and_decrypt_filename(&plaintext_name,
-							  &plaintext_name_size,
-							  dentry, lower_buf,
-							  rc);
-		if (rc) {
-			printk(KERN_ERR "%s: Error attempting to decode and "
-			       "decrypt filename; rc = [%d]\n", __func__,
-				rc);
-			goto out_free_lower_buf;
-		}
-		/* Check for bufsiz <= 0 done in sys_readlinkat() */
-		rc = copy_to_user(buf, plaintext_name,
-				  min((size_t) bufsiz, plaintext_name_size));
-		if (rc)
-			rc = -EFAULT;
-		else
-			rc = plaintext_name_size;
-		kfree(plaintext_name);
-		fsstack_copy_attr_atime(dentry->d_inode, lower_dentry->d_inode);
-	}
-out_free_lower_buf:
+	if (rc < 0)
+		goto out;
+	lower_bufsiz = rc;
+	rc = ecryptfs_decode_and_decrypt_filename(buf, bufsiz, dentry,
+						  lower_buf, lower_bufsiz);
+out:
 	kfree(lower_buf);
+	return rc;
+}
+
+static int
+ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
+{
+	char *kbuf;
+	size_t kbufsiz, copied;
+	int rc;
+
+	rc = ecryptfs_readlink_lower(dentry, &kbuf, &kbufsiz);
+	if (rc)
+		goto out;
+	copied = min_t(size_t, bufsiz, kbufsiz);
+	rc = copy_to_user(buf, kbuf, copied) ? -EFAULT : copied;
+	kfree(kbuf);
+	fsstack_copy_attr_atime(dentry->d_inode,
+				ecryptfs_dentry_to_lower(dentry)->d_inode);
 out:
 	return rc;
 }
@@ -768,7 +825,7 @@ upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
 {
 	loff_t lower_size;
 
-	lower_size = crypt_stat->num_header_bytes_at_front;
+	lower_size = ecryptfs_lower_header_size(crypt_stat);
 	if (upper_size != 0) {
 		loff_t num_extents;
 
@@ -801,8 +858,6 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 {
 	int rc = 0;
 	struct inode *inode = dentry->d_inode;
-	struct dentry *lower_dentry;
-	struct file fake_ecryptfs_file;
 	struct ecryptfs_crypt_stat *crypt_stat;
 	loff_t i_size = i_size_read(inode);
 	loff_t lower_size_before_truncate;
@@ -813,23 +868,6 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 		goto out;
 	}
 	crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
-	/* Set up a fake ecryptfs file, this is used to interface with
-	 * the file in the underlying filesystem so that the
-	 * truncation has an effect there as well. */
-	memset(&fake_ecryptfs_file, 0, sizeof(fake_ecryptfs_file));
-	fake_ecryptfs_file.f_path.dentry = dentry;
-	/* Released at out_free: label */
-	ecryptfs_set_file_private(&fake_ecryptfs_file,
-				  kmem_cache_alloc(ecryptfs_file_info_cache,
-						   GFP_KERNEL));
-	if (unlikely(!ecryptfs_file_to_private(&fake_ecryptfs_file))) {
-		rc = -ENOMEM;
-		goto out;
-	}
-	lower_dentry = ecryptfs_dentry_to_lower(dentry);
-	ecryptfs_set_file_lower(
-		&fake_ecryptfs_file,
-		ecryptfs_inode_to_private(dentry->d_inode)->lower_file);
 	/* Switch on growing or shrinking file */
 	if (ia->ia_size > i_size) {
 		char zero[] = { 0x00 };
@@ -839,7 +877,7 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 		 * this triggers code that will fill in 0's throughout
 		 * the intermediate portion of the previous end of the
 		 * file and the new and of the file */
-		rc = ecryptfs_write(&fake_ecryptfs_file, zero,
+		rc = ecryptfs_write(inode, zero,
 				    (ia->ia_size - 1), 1);
 	} else { /* ia->ia_size < i_size_read(inode) */
 		/* We're chopping off all the pages down to the page
@@ -849,13 +887,23 @@ 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)) {
-			rc = vmtruncate(inode, ia->ia_size);
-			if (rc)
-				goto out_free;
+			truncate_setsize(inode, ia->ia_size);
 			lower_ia->ia_size = ia->ia_size;
 			lower_ia->ia_valid |= ATTR_SIZE;
-			goto out_free;
+			goto out;
 		}
 		if (num_zeros) {
 			char *zeros_virt;
@@ -863,25 +911,25 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 			zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
 			if (!zeros_virt) {
 				rc = -ENOMEM;
-				goto out_free;
+				goto out;
 			}
-			rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt,
+			rc = ecryptfs_write(inode, zeros_virt,
 					    ia->ia_size, num_zeros);
 			kfree(zeros_virt);
 			if (rc) {
 				printk(KERN_ERR "Error attempting to zero out "
 				       "the remainder of the end page on "
 				       "reducing truncate; rc = [%d]\n", rc);
-				goto out_free;
+				goto out;
 			}
 		}
-		vmtruncate(inode, ia->ia_size);
+		truncate_setsize(inode, ia->ia_size);
 		rc = ecryptfs_write_inode_size_to_metadata(inode);
 		if (rc) {
 			printk(KERN_ERR	"Problem with "
 			       "ecryptfs_write_inode_size_to_metadata; "
 			       "rc = [%d]\n", rc);
-			goto out_free;
+			goto out;
 		}
 		/* We are reducing the size of the ecryptfs file, and need to
 		 * know if we need to reduce the size of the lower file. */
@@ -895,10 +943,6 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 		} else
 			lower_ia->ia_valid &= ~ATTR_SIZE;
 	}
-out_free:
-	if (ecryptfs_file_to_private(&fake_ecryptfs_file))
-		kmem_cache_free(ecryptfs_file_info_cache,
-				ecryptfs_file_to_private(&fake_ecryptfs_file));
 out:
 	return rc;
 }
@@ -1015,6 +1059,28 @@ out:
 	return rc;
 }
 
+int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
+			  struct kstat *stat)
+{
+	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+	int rc = 0;
+
+	mount_crypt_stat = &ecryptfs_superblock_to_private(
+						dentry->d_sb)->mount_crypt_stat;
+	generic_fillattr(dentry->d_inode, stat);
+	if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
+		char *target;
+		size_t targetsiz;
+
+		rc = ecryptfs_readlink_lower(dentry, &target, &targetsiz);
+		if (!rc) {
+			kfree(target);
+			stat->size = targetsiz;
+		}
+	}
+	return rc;
+}
+
 int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 		     struct kstat *stat)
 {
@@ -1039,7 +1105,7 @@ ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	if (!lower_dentry->d_inode->i_op->setxattr) {
-		rc = -ENOSYS;
+		rc = -EOPNOTSUPP;
 		goto out;
 	}
 	mutex_lock(&lower_dentry->d_inode->i_mutex);
@@ -1057,7 +1123,7 @@ ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
 	int rc = 0;
 
 	if (!lower_dentry->d_inode->i_op->getxattr) {
-		rc = -ENOSYS;
+		rc = -EOPNOTSUPP;
 		goto out;
 	}
 	mutex_lock(&lower_dentry->d_inode->i_mutex);
@@ -1084,7 +1150,7 @@ ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
 
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	if (!lower_dentry->d_inode->i_op->listxattr) {
-		rc = -ENOSYS;
+		rc = -EOPNOTSUPP;
 		goto out;
 	}
 	mutex_lock(&lower_dentry->d_inode->i_mutex);
@@ -1101,7 +1167,7 @@ static int ecryptfs_removexattr(struct dentry *dentry, const char *name)
 
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	if (!lower_dentry->d_inode->i_op->removexattr) {
-		rc = -ENOSYS;
+		rc = -EOPNOTSUPP;
 		goto out;
 	}
 	mutex_lock(&lower_dentry->d_inode->i_mutex);
@@ -1132,6 +1198,7 @@ const struct inode_operations ecryptfs_symlink_iops = {
 	.put_link = ecryptfs_put_link,
 	.permission = ecryptfs_permission,
 	.setattr = ecryptfs_setattr,
+	.getattr = ecryptfs_getattr_link,
 	.setxattr = ecryptfs_setxattr,
 	.getxattr = ecryptfs_getxattr,
 	.listxattr = ecryptfs_listxattr,