Merge tag 'upstream-4.19-rc4' of git://git.infradead.org/linux-ubifs

Richard writes:
  "This pull request contains fixes for UBIFS:
   - A wrong UBIFS assertion in mount code
   - Fix for a NULL pointer deref in mount code
   - Revert of a bad fix for xattrs"

* tag 'upstream-4.19-rc4' of git://git.infradead.org/linux-ubifs:
  Revert "ubifs: xattr: Don't operate on deleted inodes"
  ubifs: drop false positive assertion
  ubifs: Check for name being NULL while mounting

fs/ubifs/super.c

@@ -1912,7 +1912,9 @@ static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
 		mutex_unlock(&c->bu_mutex);
 	}
 
-	ubifs_assert(c, c->lst.taken_empty_lebs > 0);
+	if (!c->need_recovery)
+		ubifs_assert(c, c->lst.taken_empty_lebs > 0);
+
 	return 0;
 }
 
@@ -1954,6 +1956,9 @@ static struct ubi_volume_desc *open_ubi(const char *name, int mode)
 	int dev, vol;
 	char *endptr;
 
+	if (!name || !*name)
+		return ERR_PTR(-EINVAL);
+
 	/* First, try to open using the device node path method */
 	ubi = ubi_open_volume_path(name, mode);
 	if (!IS_ERR(ubi))

fs/ubifs/xattr.c

@@ -152,12 +152,6 @@ static int create_xattr(struct ubifs_info *c, struct inode *host,
 	ui->data_len = size;
 
 	mutex_lock(&host_ui->ui_mutex);
-
-	if (!host->i_nlink) {
-		err = -ENOENT;
-		goto out_noent;
-	}
-
 	host->i_ctime = current_time(host);
 	host_ui->xattr_cnt += 1;
 	host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm));
@@ -190,7 +184,6 @@ static int create_xattr(struct ubifs_info *c, struct inode *host,
 	host_ui->xattr_size -= CALC_XATTR_BYTES(size);
 	host_ui->xattr_names -= fname_len(nm);
 	host_ui->flags &= ~UBIFS_CRYPT_FL;
-out_noent:
 	mutex_unlock(&host_ui->ui_mutex);
 out_free:
 	make_bad_inode(inode);
@@ -242,12 +235,6 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
 	mutex_unlock(&ui->ui_mutex);
 
 	mutex_lock(&host_ui->ui_mutex);
-
-	if (!host->i_nlink) {
-		err = -ENOENT;
-		goto out_noent;
-	}
-
 	host->i_ctime = current_time(host);
 	host_ui->xattr_size -= CALC_XATTR_BYTES(old_size);
 	host_ui->xattr_size += CALC_XATTR_BYTES(size);
@@ -269,7 +256,6 @@ static int change_xattr(struct ubifs_info *c, struct inode *host,
 out_cancel:
 	host_ui->xattr_size -= CALC_XATTR_BYTES(size);
 	host_ui->xattr_size += CALC_XATTR_BYTES(old_size);
-out_noent:
 	mutex_unlock(&host_ui->ui_mutex);
 	make_bad_inode(inode);
 out_free:
@@ -496,12 +482,6 @@ static int remove_xattr(struct ubifs_info *c, struct inode *host,
 		return err;
 
 	mutex_lock(&host_ui->ui_mutex);
-
-	if (!host->i_nlink) {
-		err = -ENOENT;
-		goto out_noent;
-	}
-
 	host->i_ctime = current_time(host);
 	host_ui->xattr_cnt -= 1;
 	host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm));
@@ -521,7 +501,6 @@ static int remove_xattr(struct ubifs_info *c, struct inode *host,
 	host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm));
 	host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
 	host_ui->xattr_names += fname_len(nm);
-out_noent:
 	mutex_unlock(&host_ui->ui_mutex);
 	ubifs_release_budget(c, &req);
 	make_bad_inode(inode);
@@ -561,9 +540,6 @@ static int ubifs_xattr_remove(struct inode *host, const char *name)
 
 	ubifs_assert(c, inode_is_locked(host));
 
-	if (!host->i_nlink)
-		return -ENOENT;
-
 	if (fname_len(&nm) > UBIFS_MAX_NLEN)
 		return -ENAMETOOLONG;