UDF: check for allocated memory for data of new inodes
[cascardo/linux.git] / fs / ecryptfs / inode.c
index 11f5e50..83e94fe 100644 (file)
@@ -3,7 +3,7 @@
  *
  * Copyright (C) 1997-2004 Erez Zadok
  * Copyright (C) 2001-2004 Stony Brook University
- * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Copyright (C) 2004-2007 International Business Machines Corp.
  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
  *              Michael C. Thompsion <mcthomps@us.ibm.com>
  *
@@ -38,7 +38,7 @@ static struct dentry *lock_parent(struct dentry *dentry)
        struct dentry *dir;
 
        dir = dget(dentry->d_parent);
-       mutex_lock(&(dir->d_inode->i_mutex));
+       mutex_lock_nested(&(dir->d_inode->i_mutex), I_MUTEX_PARENT);
        return dir;
 }
 
@@ -161,17 +161,17 @@ static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file,
        ecryptfs_set_file_lower(&fake_file, lower_file);
        rc = ecryptfs_fill_zeros(&fake_file, 1);
        if (rc) {
-               ECRYPTFS_SET_FLAG(
-                       ecryptfs_inode_to_private(inode)->crypt_stat.flags,
-                       ECRYPTFS_SECURITY_WARNING);
+               ecryptfs_inode_to_private(inode)->crypt_stat.flags |=
+                       ECRYPTFS_SECURITY_WARNING;
                ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros "
                                "in file; rc = [%d]\n", rc);
                goto out;
        }
        i_size_write(inode, 0);
-       ecryptfs_write_inode_size_to_header(lower_file, lower_inode, inode);
-       ECRYPTFS_SET_FLAG(ecryptfs_inode_to_private(inode)->crypt_stat.flags,
-                         ECRYPTFS_NEW_FILE);
+       rc = ecryptfs_write_inode_size_to_metadata(lower_file, lower_inode,
+                       inode, ecryptfs_dentry,
+                       ECRYPTFS_LOWER_I_MUTEX_NOT_HELD);
+       ecryptfs_inode_to_private(inode)->crypt_stat.flags |= ECRYPTFS_NEW_FILE;
 out:
        return rc;
 }
@@ -199,10 +199,7 @@ static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
                        lower_dentry->d_name.name);
        inode = ecryptfs_dentry->d_inode;
        crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
-       lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR;
-#if BITS_PER_LONG != 32
-       lower_flags |= O_LARGEFILE;
-#endif
+       lower_flags = ((O_CREAT | O_TRUNC) & O_ACCMODE) | O_RDWR;
        lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
        /* Corresponding fput() at end of this function */
        if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
@@ -214,10 +211,10 @@ static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
        lower_inode = lower_dentry->d_inode;
        if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
                ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
-               ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
+               crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
                goto out_fput;
        }
-       ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_NEW_FILE);
+       crypt_stat->flags |= ECRYPTFS_NEW_FILE;
        ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
        rc = ecryptfs_new_file_context(ecryptfs_dentry);
        if (rc) {
@@ -225,7 +222,7 @@ static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
                                "context\n");
                goto out_fput;
        }
-       rc = ecryptfs_write_headers(ecryptfs_dentry, lower_file);
+       rc = ecryptfs_write_metadata(ecryptfs_dentry, lower_file);
        if (rc) {
                ecryptfs_printk(KERN_DEBUG, "Error writing headers\n");
                goto out_fput;
@@ -287,6 +284,7 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
        char *encoded_name;
        unsigned int encoded_namelen;
        struct ecryptfs_crypt_stat *crypt_stat = NULL;
+       struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
        char *page_virt = NULL;
        struct inode *lower_inode;
        u64 file_size;
@@ -361,34 +359,44 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
                goto out;
        }
        /* Released in this function */
-       page_virt =
-           (char *)kmem_cache_alloc(ecryptfs_header_cache_2,
-                                    GFP_USER);
+       page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2,
+                                     GFP_USER);
        if (!page_virt) {
                rc = -ENOMEM;
                ecryptfs_printk(KERN_ERR,
                                "Cannot ecryptfs_kmalloc a page\n");
                goto out_dput;
        }
-       memset(page_virt, 0, PAGE_CACHE_SIZE);
-       rc = ecryptfs_read_header_region(page_virt, lower_dentry, nd->mnt);
        crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
-       if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_POLICY_APPLIED))
+       if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
                ecryptfs_set_default_sizes(crypt_stat);
+       rc = ecryptfs_read_and_validate_header_region(page_virt, lower_dentry,
+                                                     nd->mnt);
        if (rc) {
-               rc = 0;
-               ecryptfs_printk(KERN_WARNING, "Error reading header region;"
-                               " assuming unencrypted\n");
-       } else {
-               if (!contains_ecryptfs_marker(page_virt
-                                             + ECRYPTFS_FILE_SIZE_BYTES)) {
+               rc = ecryptfs_read_and_validate_xattr_region(page_virt, dentry);
+               if (rc) {
+                       printk(KERN_DEBUG "Valid metadata not found in header "
+                              "region or xattr region; treating file as "
+                              "unencrypted\n");
+                       rc = 0;
                        kmem_cache_free(ecryptfs_header_cache_2, page_virt);
                        goto out;
                }
+               crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+       }
+       mount_crypt_stat = &ecryptfs_superblock_to_private(
+               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->header_extent_size
+                                    + i_size_read(lower_dentry->d_inode));
+               else
+                       file_size = i_size_read(lower_dentry->d_inode);
+       } else {
                memcpy(&file_size, page_virt, sizeof(file_size));
                file_size = be64_to_cpu(file_size);
-               i_size_write(dentry->d_inode, (loff_t)file_size);
        }
+       i_size_write(dentry->d_inode, (loff_t)file_size);
        kmem_cache_free(ecryptfs_header_cache_2, page_virt);
        goto out;
 
@@ -782,20 +790,45 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
                        goto out_fput;
                }
                i_size_write(inode, new_length);
-               rc = ecryptfs_write_inode_size_to_header(lower_file,
-                                                        lower_dentry->d_inode,
-                                                        inode);
+               rc = ecryptfs_write_inode_size_to_metadata(
+                       lower_file, lower_dentry->d_inode, inode, dentry,
+                       ECRYPTFS_LOWER_I_MUTEX_NOT_HELD);
                if (rc) {
-                       ecryptfs_printk(KERN_ERR,
-                                       "Problem with ecryptfs_write"
-                                       "_inode_size\n");
+                       printk(KERN_ERR "Problem with "
+                              "ecryptfs_write_inode_size_to_metadata; "
+                              "rc = [%d]\n", rc);
                        goto out_fput;
                }
        } else { /* new_length < i_size_read(inode) */
+               pgoff_t index = 0;
+               int end_pos_in_page = -1;
+
+               if (new_length != 0) {
+                       index = ((new_length - 1) >> PAGE_CACHE_SHIFT);
+                       end_pos_in_page = ((new_length - 1) & ~PAGE_CACHE_MASK);
+               }
+               if (end_pos_in_page != (PAGE_CACHE_SIZE - 1)) {
+                       if ((rc = ecryptfs_write_zeros(&fake_ecryptfs_file,
+                                                      index,
+                                                      (end_pos_in_page + 1),
+                                                      ((PAGE_CACHE_SIZE - 1)
+                                                       - end_pos_in_page)))) {
+                               printk(KERN_ERR "Error attempting to zero out "
+                                      "the remainder of the end page on "
+                                      "reducing truncate; rc = [%d]\n", rc);
+                               goto out_fput;
+                       }
+               }
                vmtruncate(inode, new_length);
-               ecryptfs_write_inode_size_to_header(lower_file,
-                                                   lower_dentry->d_inode,
-                                                   inode);
+               rc = ecryptfs_write_inode_size_to_metadata(
+                       lower_file, lower_dentry->d_inode, inode, dentry,
+                       ECRYPTFS_LOWER_I_MUTEX_NOT_HELD);
+               if (rc) {
+                       printk(KERN_ERR "Problem with "
+                              "ecryptfs_write_inode_size_to_metadata; "
+                              "rc = [%d]\n", rc);
+                       goto out_fput;
+               }
                /* We are reducing the size of the ecryptfs file, and need to
                 * know if we need to reduce the size of the lower file. */
                lower_size_before_truncate =
@@ -861,9 +894,54 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
        struct ecryptfs_crypt_stat *crypt_stat;
 
        crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
-       lower_dentry = ecryptfs_dentry_to_lower(dentry);
+       if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED))
+               ecryptfs_init_crypt_stat(crypt_stat);
        inode = dentry->d_inode;
        lower_inode = ecryptfs_inode_to_lower(inode);
+       lower_dentry = ecryptfs_dentry_to_lower(dentry);
+       mutex_lock(&crypt_stat->cs_mutex);
+       if (S_ISDIR(dentry->d_inode->i_mode))
+               crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
+       else if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
+                || !(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
+               struct vfsmount *lower_mnt;
+               struct file *lower_file = NULL;
+               struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+               int lower_flags;
+
+               lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
+               lower_flags = O_RDONLY;
+               if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry,
+                                                  lower_mnt, lower_flags))) {
+                       printk(KERN_ERR
+                              "Error opening lower file; rc = [%d]\n", rc);
+                       mutex_unlock(&crypt_stat->cs_mutex);
+                       goto out;
+               }
+               mount_crypt_stat = &ecryptfs_superblock_to_private(
+                       dentry->d_sb)->mount_crypt_stat;
+               if ((rc = ecryptfs_read_metadata(dentry, lower_file))) {
+                       if (!(mount_crypt_stat->flags
+                             & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
+                               rc = -EIO;
+                               printk(KERN_WARNING "Attempt to read file that "
+                                      "is not in a valid eCryptfs format, "
+                                      "and plaintext passthrough mode is not "
+                                      "enabled; returning -EIO\n");
+
+                               mutex_unlock(&crypt_stat->cs_mutex);
+                               fput(lower_file);
+                               goto out;
+                       }
+                       rc = 0;
+                       crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
+                       mutex_unlock(&crypt_stat->cs_mutex);
+                       fput(lower_file);
+                       goto out;
+               }
+               fput(lower_file);
+       }
+       mutex_unlock(&crypt_stat->cs_mutex);
        if (ia->ia_valid & ATTR_SIZE) {
                ecryptfs_printk(KERN_DEBUG,
                                "ia->ia_valid = [0x%x] ATTR_SIZE" " = [0x%x]\n",
@@ -882,7 +960,7 @@ out:
        return rc;
 }
 
-static int
+int
 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
                  size_t size, int flags)
 {
@@ -902,7 +980,7 @@ out:
        return rc;
 }
 
-static ssize_t
+ssize_t
 ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
                  size_t size)
 {
@@ -972,7 +1050,7 @@ int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
        return 0;
 }
 
-struct inode_operations ecryptfs_symlink_iops = {
+const struct inode_operations ecryptfs_symlink_iops = {
        .readlink = ecryptfs_readlink,
        .follow_link = ecryptfs_follow_link,
        .put_link = ecryptfs_put_link,
@@ -984,7 +1062,7 @@ struct inode_operations ecryptfs_symlink_iops = {
        .removexattr = ecryptfs_removexattr
 };
 
-struct inode_operations ecryptfs_dir_iops = {
+const struct inode_operations ecryptfs_dir_iops = {
        .create = ecryptfs_create,
        .lookup = ecryptfs_lookup,
        .link = ecryptfs_link,
@@ -1002,7 +1080,7 @@ struct inode_operations ecryptfs_dir_iops = {
        .removexattr = ecryptfs_removexattr
 };
 
-struct inode_operations ecryptfs_main_iops = {
+const struct inode_operations ecryptfs_main_iops = {
        .permission = ecryptfs_permission,
        .setattr = ecryptfs_setattr,
        .setxattr = ecryptfs_setxattr,