ubifs: fix use-after-free on symlink traversal

free the symlink body after the same RCU delay we have for freeing the struct inode itself, so that traversal during RCU pathwalk wouldn't step into freed memory. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-03-26 01:40:38 +00:00
parent 4fdcfab5b5
commit 0cdc17ebd2
1 changed files with 1 additions and 3 deletions
@@ -276,14 +276,12 @@ static void ubifs_i_callback(struct rcu_head *head)
 {
 	struct inode *inode = container_of(head, struct inode, i_rcu);
 	struct ubifs_inode *ui = ubifs_inode(inode);
+	kfree(ui->data);
 	kmem_cache_free(ubifs_inode_slab, ui);
 }

 static void ubifs_destroy_inode(struct inode *inode)
 {
-	struct ubifs_inode *ui = ubifs_inode(inode);
-
-	kfree(ui->data);
 	call_rcu(&inode->i_rcu, ubifs_i_callback);
 }