From: Liu Jian liujian56@huawei.com
[ Upstream commit 221a1f4ac12d2ab46246c160b2e00d1b1160d5d9 ]
In uio_dev_add_attributes() error handing case, idev is used after device_unregister(), in which 'idev' has been released, touch idev cause use-after-free.
Fixes: a93e7b331568 ("uio: Prevent device destruction while fds are open") Signed-off-by: Liu Jian liujian56@huawei.com Reviewed-by: Hamish Martin hamish.martin@alliedtelesis.co.nz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/uio/uio.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c index 4e9b0ff79b131..7c18536a3742a 100644 --- a/drivers/uio/uio.c +++ b/drivers/uio/uio.c @@ -944,6 +944,7 @@ int __uio_register_device(struct module *owner, return ret; }
+ device_initialize(&idev->dev); idev->dev.devt = MKDEV(uio_major, idev->minor); idev->dev.class = &uio_class; idev->dev.parent = parent; @@ -954,7 +955,7 @@ int __uio_register_device(struct module *owner, if (ret) goto err_device_create;
- ret = device_register(&idev->dev); + ret = device_add(&idev->dev); if (ret) goto err_device_create;
@@ -986,9 +987,10 @@ int __uio_register_device(struct module *owner, err_request_irq: uio_dev_del_attributes(idev); err_uio_dev_add_attributes: - device_unregister(&idev->dev); + device_del(&idev->dev); err_device_create: uio_free_minor(idev); + put_device(&idev->dev); return ret; } EXPORT_SYMBOL_GPL(__uio_register_device);