[PATCH 4.14 136/167] Btrfs: fix extent state leak from tree log

Greg Kroah-Hartman
2018-02-21T12:49:07Z

From: Liu Bo <bo.li.liu@oracle.com>

commit 55237a5f2431a72435e3ed39e4306e973c0446b7 upstream.

It's possible that btrfs_sync_log() bails out after one of the two
btrfs_write_marked_extents() which convert extent state's state bit into
EXTENT_NEED_WAIT from EXTENT_DIRTY/EXTENT_NEW, however only EXTENT_DIRTY
and EXTENT_NEW are searched by free_log_tree() so that those extent states
with EXTENT_NEED_WAIT lead to memory leak.

cc: <stable@vger.kernel.org>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/btrfs/tree-log.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -3047,13 +3047,14 @@ static void free_log_tree(struct btrfs_t

while (1) {
ret = find_first_extent_bit(&log->dirty_log_pages,
- 0, &start, &end, EXTENT_DIRTY | EXTENT_NEW,
+ 0, &start, &end,
+ EXTENT_DIRTY | EXTENT_NEW | EXTENT_NEED_WAIT,
NULL);
if (ret)
break;

clear_extent_bits(&log->dirty_log_pages, start, end,
- EXTENT_DIRTY | EXTENT_NEW);
+ EXTENT_DIRTY | EXTENT_NEW | EXTENT_NEED_WAIT);
}

/*