btrfs: delayed-ref: double free in btrfs_add_delayed_tree_ref()

There is a cut and paste error so instead of freeing "head_ref", we free
"ref" twice.

Fixes: 3368d001ba5d ('btrfs: qgroup: Record possible quota-related extent for qgroup.')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index fd64fd0..ac3e81d 100644 (file)
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -650,18 +650,13 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
                return -ENOMEM;
 
        head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
-       if (!head_ref) {
-               kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
-               return -ENOMEM;
-       }
+       if (!head_ref)
+               goto free_ref;
 
        if (fs_info->quota_enabled && is_fstree(ref_root)) {
                record = kmalloc(sizeof(*record), GFP_NOFS);
-               if (!record) {
-                       kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
-                       kmem_cache_free(btrfs_delayed_ref_head_cachep, ref);
-                       return -ENOMEM;
-               }
+               if (!record)
+                       goto free_head_ref;
        }
 
        head_ref->extent_op = extent_op;
@@ -682,6 +677,13 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
        spin_unlock(&delayed_refs->lock);
 
        return 0;
+
+free_head_ref:
+       kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
+free_ref:
+       kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
+
+       return -ENOMEM;
 }
 
 /*