hfsplus: fix logic of alloc/free b-tree node

The hfs_bmap_alloc() and hfs_bmap_free() modify
the b-tree's counters and nodes' bitmap of b-tree.
However, hfs_btree_write() synchronizes the state of
in-core b-tree's counters and node's bitmap with
b-tree's descriptor in header node. Postponing this
synchronization could result in inconsistent state of
file system volume. This patch adds calling of
hfs_btree_write() in hfs_bmap_alloc() and hfs_bmap_free()
methods.

cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
cc: Yangtao Li <frank.li@vivo.com>
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Link: https://lore.kernel.org/r/20260403230556.614171-4-slava@dubeyko.com
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>

diff --git a/fs/hfsplus/btree.c b/fs/hfsplus/btree.c
index 80aa816ae1c0288bdff34bc95485f00aae8fb92c..761c74ccd6531ebf3661ad2c712dc8e57b1ce0fe 100644 (file)
--- a/fs/hfsplus/btree.c
+++ b/fs/hfsplus/btree.c
@@ -564,6 +564,7 @@ struct hfs_bnode *hfs_bmap_alloc(struct hfs_btree *tree)
                                                set_page_dirty(page);
                                                kunmap_local(data);
                                                tree->free_nodes--;
+                                               hfs_btree_write(tree);
                                                mark_inode_dirty(tree->inode);
                                                hfs_bnode_put(node);
                                                return hfs_bnode_create(tree,
@@ -585,6 +586,7 @@ struct hfs_bnode *hfs_bmap_alloc(struct hfs_btree *tree)
                if (!nidx) {
                        hfs_dbg("create new bmap node\n");
                        next_node = hfs_bmap_new_bmap(node, idx);
+                       hfs_btree_write(tree);
                } else
                        next_node = hfs_bnode_find(tree, nidx);
                hfs_bnode_put(node);
@@ -655,6 +657,7 @@ void hfs_bmap_free(struct hfs_bnode *node)
                        nidx, node->type);
        } else {
                tree->free_nodes++;
+               hfs_btree_write(tree);
                mark_inode_dirty(tree->inode);
        }