From: Filipe Manana <fdmanana@xxxxxxxx>
commit 72c9925f87c8b74f36f8e75a4cd93d964538d3ca upstream.
At btrfs_copy_root(), if the call to btrfs_inc_ref() fails we end up
returning without unlocking and releasing our reference on the extent
buffer named "cow" we previously allocated with btrfs_alloc_tree_block().
So fix that by unlocking the extent buffer and dropping our reference on
it before returning.
Fixes: be20aa9dbadc8c ("Btrfs: Add mount option to turn off data cow")
CC: stable@xxxxxxxxxxxxxxx # 4.4+
Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/ctree.c | 2 ++
1 file changed, 2 insertions(+)
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -222,6 +222,8 @@ int btrfs_copy_root(struct btrfs_trans_h
else
ret = btrfs_inc_ref(trans, root, cow, 0);
if (ret) {
+ btrfs_tree_unlock(cow);
+ free_extent_buffer(cow);
btrfs_abort_transaction(trans, ret);
return ret;
}
