Merge tag 'for-6.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - in send, fix duplicated rmdir operations when using extrefs
   (hardlinks), receive can fail with ENOENT

 - fixup of error check when reading extent root in ref-verify and
   damaged roots are allowed by mount option (found by smatch)

 - fix freeing partially initialized fs info (found by syzkaller)

 - fix use-after-free when printing ref_tracking status of delayed
   inodes

* tag 'for-6.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: ref-verify: fix IS_ERR() vs NULL check in btrfs_build_ref_tree()
  btrfs: fix delayed_node ref_tracker use after free
  btrfs: send: fix duplicated rmdir operations when using extrefs
  btrfs: directly free partially initialized fs_info in btrfs_check_leaked_roots()

Author: torvalds

fs/btrfs/delayed-inode.c

@@ -2110,9 +2110,9 @@ void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
 
 		for (int i = 0; i < count; i++) {
 			__btrfs_kill_delayed_node(delayed_nodes[i]);
+			btrfs_delayed_node_ref_tracker_dir_print(delayed_nodes[i]);
 			btrfs_release_delayed_node(delayed_nodes[i],
 						   &delayed_node_trackers[i]);
-			btrfs_delayed_node_ref_tracker_dir_print(delayed_nodes[i]);
 		}
 	}
 }

fs/btrfs/delayed-inode.h

@@ -219,6 +219,13 @@ static inline void btrfs_delayed_node_ref_tracker_dir_print(struct btrfs_delayed
 	if (!btrfs_test_opt(node->root->fs_info, REF_TRACKER))
 		return;
 
+	/*
+	 * Only print if there are leaked references. The caller is
+	 * holding one reference, so if refs == 1 there is no leak.
+	 */
+	if (refcount_read(&node->refs) == 1)
+		return;
+
 	ref_tracker_dir_print(&node->ref_dir.dir,
 			      BTRFS_DELAYED_NODE_REF_TRACKER_DISPLAY_LIMIT);
 }

fs/btrfs/ref-verify.c

@@ -982,7 +982,7 @@ int btrfs_build_ref_tree(struct btrfs_fs_info *fs_info)
 
 	extent_root = btrfs_extent_root(fs_info, 0);
 	/* If the extent tree is damaged we cannot ignore it (IGNOREBADROOTS). */
-	if (IS_ERR(extent_root)) {
+	if (!extent_root) {
 		btrfs_warn(fs_info, "ref-verify: extent tree not available, disabling");
 		btrfs_clear_opt(fs_info->mount_opt, REF_VERIFY);
 		return 0;

fs/btrfs/send.c

@@ -4102,6 +4102,48 @@ static int refresh_ref_path(struct send_ctx *sctx, struct recorded_ref *ref)
 	return ret;
 }
 
+static int rbtree_check_dir_ref_comp(const void *k, const struct rb_node *node)
+{
+	const struct recorded_ref *data = k;
+	const struct recorded_ref *ref = rb_entry(node, struct recorded_ref, node);
+
+	if (data->dir > ref->dir)
+		return 1;
+	if (data->dir < ref->dir)
+		return -1;
+	if (data->dir_gen > ref->dir_gen)
+		return 1;
+	if (data->dir_gen < ref->dir_gen)
+		return -1;
+	return 0;
+}
+
+static bool rbtree_check_dir_ref_less(struct rb_node *node, const struct rb_node *parent)
+{
+	const struct recorded_ref *entry = rb_entry(node, struct recorded_ref, node);
+
+	return rbtree_check_dir_ref_comp(entry, parent) < 0;
+}
+
+static int record_check_dir_ref_in_tree(struct rb_root *root,
+			struct recorded_ref *ref, struct list_head *list)
+{
+	struct recorded_ref *tmp_ref;
+	int ret;
+
+	if (rb_find(ref, root, rbtree_check_dir_ref_comp))
+		return 0;
+
+	ret = dup_ref(ref, list);
+	if (ret < 0)
+		return ret;
+
+	tmp_ref = list_last_entry(list, struct recorded_ref, list);
+	rb_add(&tmp_ref->node, root, rbtree_check_dir_ref_less);
+	tmp_ref->root = root;
+	return 0;
+}
+
 static int rename_current_inode(struct send_ctx *sctx,
 				struct fs_path *current_path,
 				struct fs_path *new_path)
@@ -4129,11 +4171,11 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 	struct recorded_ref *cur;
 	struct recorded_ref *cur2;
 	LIST_HEAD(check_dirs);
+	struct rb_root rbtree_check_dirs = RB_ROOT;
 	struct fs_path *valid_path = NULL;
 	u64 ow_inode = 0;
 	u64 ow_gen;
 	u64 ow_mode;
-	u64 last_dir_ino_rm = 0;
 	bool did_overwrite = false;
 	bool is_orphan = false;
 	bool can_rename = true;
@@ -4437,7 +4479,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 					goto out;
 			}
 		}
-		ret = dup_ref(cur, &check_dirs);
+		ret = record_check_dir_ref_in_tree(&rbtree_check_dirs, cur, &check_dirs);
 		if (ret < 0)
 			goto out;
 	}
@@ -4465,7 +4507,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 		}
 
 		list_for_each_entry(cur, &sctx->deleted_refs, list) {
-			ret = dup_ref(cur, &check_dirs);
+			ret = record_check_dir_ref_in_tree(&rbtree_check_dirs, cur, &check_dirs);
 			if (ret < 0)
 				goto out;
 		}
@@ -4475,7 +4517,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 		 * We have a moved dir. Add the old parent to check_dirs
 		 */
 		cur = list_first_entry(&sctx->deleted_refs, struct recorded_ref, list);
-		ret = dup_ref(cur, &check_dirs);
+		ret = record_check_dir_ref_in_tree(&rbtree_check_dirs, cur, &check_dirs);
 		if (ret < 0)
 			goto out;
 	} else if (!S_ISDIR(sctx->cur_inode_mode)) {
@@ -4509,7 +4551,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 				if (is_current_inode_path(sctx, cur->full_path))
 					fs_path_reset(&sctx->cur_inode_path);
 			}
-			ret = dup_ref(cur, &check_dirs);
+			ret = record_check_dir_ref_in_tree(&rbtree_check_dirs, cur, &check_dirs);
 			if (ret < 0)
 				goto out;
 		}
@@ -4552,8 +4594,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 			ret = cache_dir_utimes(sctx, cur->dir, cur->dir_gen);
 			if (ret < 0)
 				goto out;
-		} else if (ret == inode_state_did_delete &&
-			   cur->dir != last_dir_ino_rm) {
+		} else if (ret == inode_state_did_delete) {
 			ret = can_rmdir(sctx, cur->dir, cur->dir_gen);
 			if (ret < 0)
 				goto out;
@@ -4565,7 +4606,6 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 				ret = send_rmdir(sctx, valid_path);
 				if (ret < 0)
 					goto out;
-				last_dir_ino_rm = cur->dir;
 			}
 		}
 	}

fs/btrfs/super.c

@@ -2068,7 +2068,13 @@ static int btrfs_get_tree_subvol(struct fs_context *fc)
 	fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
 	fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
 	if (!fs_info->super_copy || !fs_info->super_for_commit) {
-		btrfs_free_fs_info(fs_info);
+		/*
+		 * Dont call btrfs_free_fs_info() to free it as it's still
+		 * initialized partially.
+		 */
+		kfree(fs_info->super_copy);
+		kfree(fs_info->super_for_commit);
+		kvfree(fs_info);
 		return -ENOMEM;
 	}
 	btrfs_init_fs_info(fs_info);