rbd: fix double free on rbd_dev->header_name

commit 3ebe138ac642a195c7f2efdb918f464734421fd6 upstream.

If rbd_dev_image_probe() in rbd_dev_probe_parent() fails, header_name
is freed twice: once in rbd_dev_probe_parent() and then in its caller
rbd_dev_image_probe() (rbd_dev_image_probe() is called recursively to
handle parent images).

rbd_dev_probe_parent() is responsible for probing the parent, so it
shouldn't muck with clone's fields.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index b583773e4ecbfea6939b181292e984d04f1fd403..2ea515509ca62bc4e0773bd2f8048f4c298951ec 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -4851,7 +4851,6 @@ static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
 out_err:
        if (parent) {
                rbd_dev_unparent(rbd_dev);
-               kfree(rbd_dev->header_name);
                rbd_dev_destroy(parent);
        } else {
                rbd_put_client(rbdc);