Btrfs: fix use after free in btrfs_start_workers fail path

worker memory is already freed on one fail path in btrfs_start_workers,
but is still dereferenced. Switch the dereference and kfree.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 7f88628a1a72..6e4f6c50a120 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -299,8 +299,8 @@ int btrfs_start_workers(struct btrfs_workers *workers, int num_workers)
                                            "btrfs-%s-%d", workers->name,
                                            workers->num_workers + i);
                 if (IS_ERR(worker->task)) {
-                        kfree(worker);
                         ret = PTR_ERR(worker->task);
+                        kfree(worker);
                         goto fail;
                 }