btrfs: fix leak of path in btrfs_find_item

If btrfs_find_item is called with NULL path it allocates one locally but
does not free it. Affected paths are inserting an orphan item for a file
and for a subvol root.

Move the path allocation to the callers.

CC: <stable@vger.kernel.org> # 3.14+
Fixes: 3f870c289900 ("btrfs: expand btrfs_find_item() to include find_orphan_item functionality")
Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 14a72ed..f54511d 100644 (file)
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -2609,32 +2609,23 @@ static int key_search(struct extent_buffer *b, struct btrfs_key *key,
        return 0;
 }
 
-int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *found_path,
+int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *path,
                u64 iobjectid, u64 ioff, u8 key_type,
                struct btrfs_key *found_key)
 {
        int ret;
        struct btrfs_key key;
        struct extent_buffer *eb;
-       struct btrfs_path *path;
+
+       ASSERT(path);
 
        key.type = key_type;
        key.objectid = iobjectid;
        key.offset = ioff;
 
-       if (found_path == NULL) {
-               path = btrfs_alloc_path();
-               if (!path)
-                       return -ENOMEM;
-       } else
-               path = found_path;
-
        ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0);
-       if ((ret < 0) || (found_key == NULL)) {
-               if (path != found_path)
-                       btrfs_free_path(path);
+       if ((ret < 0) || (found_key == NULL))
                return ret;
-       }
 
        eb = path->nodes[0];
        if (ret && path->slots[0] >= btrfs_header_nritems(eb)) {

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 8c63419..6182e54 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1630,6 +1630,7 @@ struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
                                     bool check_ref)
 {
        struct btrfs_root *root;
+       struct btrfs_path *path;
        int ret;
 
        if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
@@ -1669,8 +1670,14 @@ again:
        if (ret)
                goto fail;
 
-       ret = btrfs_find_item(fs_info->tree_root, NULL, BTRFS_ORPHAN_OBJECTID,
+       path = btrfs_alloc_path();
+       if (!path) {
+               ret = -ENOMEM;
+               goto fail;
+       }
+       ret = btrfs_find_item(fs_info->tree_root, path, BTRFS_ORPHAN_OBJECTID,
                        location->objectid, BTRFS_ORPHAN_ITEM_KEY, NULL);
+       btrfs_free_path(path);
        if (ret < 0)
                goto fail;
        if (ret == 0)

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 9a02da1..5be45c1 100644 (file)
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -1257,10 +1257,19 @@ static int insert_orphan_item(struct btrfs_trans_handle *trans,
                              struct btrfs_root *root, u64 offset)
 {
        int ret;
-       ret = btrfs_find_item(root, NULL, BTRFS_ORPHAN_OBJECTID,
+       struct btrfs_path *path;
+
+       path = btrfs_alloc_path();
+       if (!path)
+               return -ENOMEM;
+
+       ret = btrfs_find_item(root, path, BTRFS_ORPHAN_OBJECTID,
                        offset, BTRFS_ORPHAN_ITEM_KEY, NULL);
        if (ret > 0)
                ret = btrfs_insert_orphan_item(trans, root, offset);
+
+       btrfs_free_path(path);
+
        return ret;
 }