Commit 14d4c4fa authored by Qinglang Miao's avatar Qinglang Miao Committed by Heiko Carstens
Browse files

s390/cio: fix use-after-free in ccw_device_destroy_console 



Use of sch->dev reference after the put_device() call could trigger
the use-after-free bugs.

Fix this by simply adjusting the position of put_device.

Fixes: 37db8985 ("s390/cio: add basic protected virtualization support")
Reported-by: default avatarHulk Robot <hulkci@huawei.com>
Suggested-by: default avatarCornelia Huck <cohuck@redhat.com>
Signed-off-by: default avatarQinglang Miao <miaoqinglang@huawei.com>
Reviewed-by: default avatarCornelia Huck <cohuck@redhat.com>
Reviewed-by: default avatarVineeth Vijayan <vneethv@linux.ibm.com>
[vneethv@linux.ibm.com: Slight modification in the commit-message]
Signed-off-by: default avatarVineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent 8cc0dcfd

drivers/s390/cio/device.c

+2 −2
Original line number Diff line number Diff line
@@ -1645,10 +1645,10 @@ void __init ccw_device_destroy_console(struct ccw_device *cdev) 
	struct io_subchannel_private *io_priv = to_io_private(sch);



	set_io_private(sch, NULL);

	put_device(&sch->dev);

	put_device(&cdev->dev);

	dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area),

			  io_priv->dma_area, io_priv->dma_area_dma);

	put_device(&sch->dev);

	put_device(&cdev->dev);

	kfree(io_priv);

}