lockd: fix arg parsing for grace_period and timeout.
[firefly-linux-kernel-4.4.55.git] / fs / ecryptfs / inode.c
index bc116b9ffcf2264c19fe9d725ebeea2a1954e530..2717329386d858ba9173a76e3d377efa89614394 100644 (file)
@@ -51,6 +51,98 @@ 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;
+       inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi;
+
+       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 +221,7 @@ 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 +260,8 @@ 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 +308,90 @@ 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;
-       }
-       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;
-       }
-       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;
+               d_add(dentry, NULL);
+               return 0;
        }
-       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;
+       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);
        }
-       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 +434,12 @@ 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 +462,9 @@ 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 +492,7 @@ 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 +559,7 @@ 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 +583,7 @@ 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);
@@ -521,8 +602,6 @@ static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
        struct dentry *lower_dir_dentry;
        int rc;
 
-       dentry_unhash(dentry);
-
        lower_dentry = ecryptfs_dentry_to_lower(dentry);
        dget(dentry);
        lower_dir_dentry = lock_parent(lower_dentry);
@@ -552,7 +631,7 @@ 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);
@@ -575,9 +654,6 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        struct dentry *lower_new_dir_dentry;
        struct dentry *trap = NULL;
 
-       if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
-               dentry_unhash(new_dentry);
-
        lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
        lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
        dget(lower_old_dentry);
@@ -755,7 +831,7 @@ 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;
@@ -778,18 +854,6 @@ 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;
@@ -839,6 +903,28 @@ out:
        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
@@ -855,6 +941,10 @@ 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);
@@ -911,7 +1001,7 @@ 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;
@@ -936,6 +1026,16 @@ 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)
@@ -1019,6 +1119,8 @@ ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
        }
 
        rc = vfs_setxattr(lower_dentry, name, value, size, flags);
+       if (!rc)
+               fsstack_copy_attr_all(dentry->d_inode, lower_dentry->d_inode);
 out:
        return rc;
 }
@@ -1084,21 +1186,6 @@ 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,