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: Luis Henriques <luis.henriques@canonical.com>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 4242da3b09daccbe613f43848f14076c64b7f698..59584862a01b64a0a8345b17934751f8222c10f4 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -5058,7 +5058,6 @@ 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);