1 files changed, 101 insertions, 57 deletions

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index e2d4418affac..6c55113e7222 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -142,19 +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 |=
@@ -273,7 +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);
@@ -348,14 +339,85 @@ 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
+ * @ename: 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
+ *
+ * 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 nameidata nd;
+        struct vfsmount *lower_mnt;
+        struct qstr *name;
+        int err;
+
+        name = &ecryptfs_dentry->d_name;
+        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
@@ -382,14 +444,12 @@ 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_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
+                                                 lower_dir_dentry);
         if (IS_ERR(lower_dentry)) {
                 rc = PTR_ERR(lower_dentry);
-                ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
+                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;
@@ -411,14 +471,11 @@ 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_dentry = ecryptfs_lookup_one_lower(ecryptfs_dentry,
+                                                 lower_dir_dentry);
         if (IS_ERR(lower_dentry)) {
                 rc = PTR_ERR(lower_dentry);
-                ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
+                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;
@@ -784,8 +841,6 @@ 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;
@@ -796,23 +851,6 @@ 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 };
@@ -822,7 +860,7 @@ 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
@@ -832,13 +870,23 @@ 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;
@@ -846,25 +894,25 @@ 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. */
@@ -878,10 +926,6 @@ 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;
 }