[PATCH 3.19 164/175] btrfs: fix leak of path in btrfs_find_item

Greg Kroah-Hartman
2015-03-04T06:28:09Z

From: David Sterba <dsterba@suse.cz>

commit 381cf6587f8a8a8e981bc0c1aaaa8859b51dc756 upstream.

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.

Fixes: 3f870c289900 ("btrfs: expand btrfs_find_item() to include find_orphan_item functionality")
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/btrfs/ctree.c | 17 ++++-------------
fs/btrfs/disk-io.c | 9 ++++++++-
fs/btrfs/tree-log.c | 11 ++++++++++-
3 files changed, 22 insertions(+), 15 deletions(-)

--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -2609,32 +2609,23 @@ static int key_search(struct extent_buff
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)) {
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1630,6 +1630,7 @@ struct btrfs_root *btrfs_get_fs_root(str
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)
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -1257,10 +1257,19 @@ static int insert_orphan_item(struct btr
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;
}