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Diffstat (limited to 'fs/ecryptfs/inode.c')
-rw-r--r--fs/ecryptfs/inode.c283
1 files changed, 175 insertions, 108 deletions
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 4d4cc6a90cd5..7349ade17de6 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -51,6 +51,97 @@ static void unlock_dir(struct dentry *dir)
dput(dir);
}
+static int ecryptfs_inode_test(struct inode *inode, void *lower_inode)
+{
+ if (ecryptfs_inode_to_lower(inode) == (struct inode *)lower_inode)
+ return 1;
+ return 0;
+}
+
+static int ecryptfs_inode_set(struct inode *inode, void *opaque)
+{
+ struct inode *lower_inode = opaque;
+
+ ecryptfs_set_inode_lower(inode, lower_inode);
+ fsstack_copy_attr_all(inode, lower_inode);
+ /* i_size will be overwritten for encrypted regular files */
+ fsstack_copy_inode_size(inode, lower_inode);
+ inode->i_ino = lower_inode->i_ino;
+ inode->i_version++;
+ inode->i_mapping->a_ops = &ecryptfs_aops;
+
+ if (S_ISLNK(inode->i_mode))
+ inode->i_op = &ecryptfs_symlink_iops;
+ else if (S_ISDIR(inode->i_mode))
+ inode->i_op = &ecryptfs_dir_iops;
+ else
+ inode->i_op = &ecryptfs_main_iops;
+
+ if (S_ISDIR(inode->i_mode))
+ inode->i_fop = &ecryptfs_dir_fops;
+ else if (special_file(inode->i_mode))
+ init_special_inode(inode, inode->i_mode, inode->i_rdev);
+ else
+ inode->i_fop = &ecryptfs_main_fops;
+
+ return 0;
+}
+
+static struct inode *__ecryptfs_get_inode(struct inode *lower_inode,
+ struct super_block *sb)
+{
+ struct inode *inode;
+
+ if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb))
+ return ERR_PTR(-EXDEV);
+ if (!igrab(lower_inode))
+ return ERR_PTR(-ESTALE);
+ inode = iget5_locked(sb, (unsigned long)lower_inode,
+ ecryptfs_inode_test, ecryptfs_inode_set,
+ lower_inode);
+ if (!inode) {
+ iput(lower_inode);
+ return ERR_PTR(-EACCES);
+ }
+ if (!(inode->i_state & I_NEW))
+ iput(lower_inode);
+
+ return inode;
+}
+
+struct inode *ecryptfs_get_inode(struct inode *lower_inode,
+ struct super_block *sb)
+{
+ struct inode *inode = __ecryptfs_get_inode(lower_inode, sb);
+
+ if (!IS_ERR(inode) && (inode->i_state & I_NEW))
+ unlock_new_inode(inode);
+
+ return inode;
+}
+
+/**
+ * ecryptfs_interpose
+ * @lower_dentry: Existing dentry in the lower filesystem
+ * @dentry: ecryptfs' dentry
+ * @sb: ecryptfs's super_block
+ *
+ * Interposes upper and lower dentries.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_interpose(struct dentry *lower_dentry,
+ struct dentry *dentry, struct super_block *sb)
+{
+ struct inode *inode = ecryptfs_get_inode(lower_dentry->d_inode, sb);
+
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
+ d_instantiate(dentry, inode);
+
+ return 0;
+}
+
/**
* ecryptfs_create_underlying_file
* @lower_dir_inode: inode of the parent in the lower fs of the new file
@@ -129,7 +220,7 @@ ecryptfs_do_create(struct inode *directory_inode,
goto out_lock;
}
rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
- directory_inode->i_sb, 0);
+ directory_inode->i_sb);
if (rc) {
ecryptfs_printk(KERN_ERR, "Failure in ecryptfs_interpose\n");
goto out_lock;
@@ -168,7 +259,8 @@ static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
"context; rc = [%d]\n", rc);
goto out;
}
- rc = ecryptfs_get_lower_file(ecryptfs_dentry);
+ rc = ecryptfs_get_lower_file(ecryptfs_dentry,
+ ecryptfs_dentry->d_inode);
if (rc) {
printk(KERN_ERR "%s: Error attempting to initialize "
"the lower file for the dentry with name "
@@ -215,102 +307,90 @@ out:
return rc;
}
+static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
+{
+ struct ecryptfs_crypt_stat *crypt_stat;
+ int rc;
+
+ rc = ecryptfs_get_lower_file(dentry, inode);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to initialize "
+ "the lower file for the dentry with name "
+ "[%s]; rc = [%d]\n", __func__,
+ dentry->d_name.name, rc);
+ return rc;
+ }
+
+ crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
+ /* TODO: lock for crypt_stat comparison */
+ if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
+ ecryptfs_set_default_sizes(crypt_stat);
+
+ rc = ecryptfs_read_and_validate_header_region(inode);
+ ecryptfs_put_lower_file(inode);
+ if (rc) {
+ rc = ecryptfs_read_and_validate_xattr_region(dentry, inode);
+ if (!rc)
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ }
+
+ /* Must return 0 to allow non-eCryptfs files to be looked up, too */
+ return 0;
+}
+
/**
- * ecryptfs_lookup_and_interpose_lower - Perform a lookup
+ * ecryptfs_lookup_interpose - Dentry interposition for a lookup
*/
-int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry,
- struct dentry *lower_dentry,
- struct inode *ecryptfs_dir_inode)
+static int ecryptfs_lookup_interpose(struct dentry *dentry,
+ struct dentry *lower_dentry,
+ struct inode *dir_inode)
{
- struct dentry *lower_dir_dentry;
+ struct inode *inode, *lower_inode = lower_dentry->d_inode;
+ struct ecryptfs_dentry_info *dentry_info;
struct vfsmount *lower_mnt;
- struct inode *lower_inode;
- struct ecryptfs_crypt_stat *crypt_stat;
- char *page_virt = NULL;
- int put_lower = 0, rc = 0;
-
- lower_dir_dentry = lower_dentry->d_parent;
- lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(
- ecryptfs_dentry->d_parent));
- lower_inode = lower_dentry->d_inode;
- fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode);
+ int rc = 0;
+
+ lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent));
+ fsstack_copy_attr_atime(dir_inode, lower_dentry->d_parent->d_inode);
BUG_ON(!lower_dentry->d_count);
- ecryptfs_set_dentry_private(ecryptfs_dentry,
- kmem_cache_alloc(ecryptfs_dentry_info_cache,
- GFP_KERNEL));
- if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) {
- rc = -ENOMEM;
+
+ dentry_info = kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
+ ecryptfs_set_dentry_private(dentry, dentry_info);
+ if (!dentry_info) {
printk(KERN_ERR "%s: Out of memory whilst attempting "
"to allocate ecryptfs_dentry_info struct\n",
__func__);
- goto out_put;
+ dput(lower_dentry);
+ mntput(lower_mnt);
+ d_drop(dentry);
+ return -ENOMEM;
}
- ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry);
- ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt);
+ ecryptfs_set_dentry_lower(dentry, lower_dentry);
+ ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt);
+
if (!lower_dentry->d_inode) {
/* We want to add because we couldn't find in lower */
- d_add(ecryptfs_dentry, NULL);
- goto out;
+ d_add(dentry, NULL);
+ return 0;
}
- rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry,
- ecryptfs_dir_inode->i_sb,
- ECRYPTFS_INTERPOSE_FLAG_D_ADD);
- if (rc) {
- printk(KERN_ERR "%s: Error interposing; rc = [%d]\n",
- __func__, rc);
- goto out;
+ inode = __ecryptfs_get_inode(lower_inode, dir_inode->i_sb);
+ if (IS_ERR(inode)) {
+ printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n",
+ __func__, PTR_ERR(inode));
+ return PTR_ERR(inode);
}
- if (S_ISDIR(lower_inode->i_mode))
- goto out;
- if (S_ISLNK(lower_inode->i_mode))
- goto out;
- if (special_file(lower_inode->i_mode))
- goto out;
- /* Released in this function */
- page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER);
- if (!page_virt) {
- printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n",
- __func__);
- rc = -ENOMEM;
- goto out;
- }
- rc = ecryptfs_get_lower_file(ecryptfs_dentry);
- if (rc) {
- printk(KERN_ERR "%s: Error attempting to initialize "
- "the lower file for the dentry with name "
- "[%s]; rc = [%d]\n", __func__,
- ecryptfs_dentry->d_name.name, rc);
- goto out_free_kmem;
- }
- put_lower = 1;
- crypt_stat = &ecryptfs_inode_to_private(
- ecryptfs_dentry->d_inode)->crypt_stat;
- /* TODO: lock for crypt_stat comparison */
- if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
- ecryptfs_set_default_sizes(crypt_stat);
- 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 (S_ISREG(inode->i_mode)) {
+ rc = ecryptfs_i_size_read(dentry, inode);
if (rc) {
- rc = 0;
- goto out_free_kmem;
+ make_bad_inode(inode);
+ return rc;
}
- crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
}
- ecryptfs_i_size_init(page_virt, ecryptfs_dentry->d_inode);
-out_free_kmem:
- kmem_cache_free(ecryptfs_header_cache_2, page_virt);
- goto out;
-out_put:
- dput(lower_dentry);
- mntput(lower_mnt);
- d_drop(ecryptfs_dentry);
-out:
- if (put_lower)
- ecryptfs_put_lower_file(ecryptfs_dentry->d_inode);
+
+ if (inode->i_state & I_NEW)
+ unlock_new_inode(inode);
+ d_add(dentry, inode);
+
return rc;
}
@@ -353,12 +433,12 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
goto out_d_drop;
}
if (lower_dentry->d_inode)
- goto lookup_and_interpose;
+ goto interpose;
mount_crypt_stat = &ecryptfs_superblock_to_private(
ecryptfs_dentry->d_sb)->mount_crypt_stat;
if (!(mount_crypt_stat
&& (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)))
- goto lookup_and_interpose;
+ goto interpose;
dput(lower_dentry);
rc = ecryptfs_encrypt_and_encode_filename(
&encrypted_and_encoded_name, &encrypted_and_encoded_name_size,
@@ -381,9 +461,9 @@ static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
encrypted_and_encoded_name);
goto out_d_drop;
}
-lookup_and_interpose:
- rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry,
- ecryptfs_dir_inode);
+interpose:
+ rc = ecryptfs_lookup_interpose(ecryptfs_dentry, lower_dentry,
+ ecryptfs_dir_inode);
goto out;
out_d_drop:
d_drop(ecryptfs_dentry);
@@ -411,7 +491,7 @@ static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
lower_new_dentry);
if (rc || !lower_new_dentry->d_inode)
goto out_lock;
- rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb, 0);
+ rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
if (rc)
goto out_lock;
fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
@@ -478,7 +558,7 @@ static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
kfree(encoded_symname);
if (rc || !lower_dentry->d_inode)
goto out_lock;
- rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
if (rc)
goto out_lock;
fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
@@ -502,7 +582,7 @@ static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
rc = vfs_mkdir(lower_dir_dentry->d_inode, lower_dentry, mode);
if (rc || !lower_dentry->d_inode)
goto out;
- rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
if (rc)
goto out;
fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
@@ -527,6 +607,8 @@ static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
dget(lower_dentry);
rc = vfs_rmdir(lower_dir_dentry->d_inode, lower_dentry);
dput(lower_dentry);
+ if (!rc && dentry->d_inode)
+ clear_nlink(dentry->d_inode);
fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
dir->i_nlink = lower_dir_dentry->d_inode->i_nlink;
unlock_dir(lower_dir_dentry);
@@ -548,7 +630,7 @@ ecryptfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
if (rc || !lower_dentry->d_inode)
goto out;
- rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
+ rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
if (rc)
goto out;
fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);
@@ -748,7 +830,7 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
lower_ia->ia_valid &= ~ATTR_SIZE;
return 0;
}
- rc = ecryptfs_get_lower_file(dentry);
+ rc = ecryptfs_get_lower_file(dentry, inode);
if (rc)
return rc;
crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
@@ -904,7 +986,7 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
mount_crypt_stat = &ecryptfs_superblock_to_private(
dentry->d_sb)->mount_crypt_stat;
- rc = ecryptfs_get_lower_file(dentry);
+ rc = ecryptfs_get_lower_file(dentry, inode);
if (rc) {
mutex_unlock(&crypt_stat->cs_mutex);
goto out;
@@ -1077,21 +1159,6 @@ out:
return rc;
}
-int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
-{
- if ((ecryptfs_inode_to_lower(inode)
- == (struct inode *)candidate_lower_inode))
- return 1;
- else
- return 0;
-}
-
-int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
-{
- ecryptfs_init_inode(inode, (struct inode *)lower_inode);
- return 0;
-}
-
const struct inode_operations ecryptfs_symlink_iops = {
.readlink = ecryptfs_readlink,
.follow_link = ecryptfs_follow_link,