From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Dan Carpenter , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 4.14 21/89] uio: potential double frees if __uio_register_device() fails Date: Sun, 2 Sep 2018 13:06:33 +0000 Message-ID: <20180902064918.183387-21-alexander.levin@microsoft.com> References: <20180902064918.183387-1-alexander.levin@microsoft.com> In-Reply-To: <20180902064918.183387-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Dan Carpenter [ Upstream commit f019f07ecf6a6b8bd6d7853bce70925d90af02d1 ] The uio_unregister_device() function assumes that if "info->uio_dev" is non-NULL that means "info" is fully allocated. Setting info->uio_de has to be the last thing in the function. In the current code, if request_threaded_irq() fails then we return with info->uio_dev set to non-NULL but info is not fully allocated and it can lead to double frees. Fixes: beafc54c4e2f ("UIO: Add the User IO core code") Signed-off-by: Dan Carpenter Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/uio/uio.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c index ff04b7f8549f..41784798c789 100644 --- a/drivers/uio/uio.c +++ b/drivers/uio/uio.c @@ -841,8 +841,6 @@ int __uio_register_device(struct module *owner, if (ret) goto err_uio_dev_add_attributes; =20 - info->uio_dev =3D idev; - if (info->irq && (info->irq !=3D UIO_IRQ_CUSTOM)) { /* * Note that we deliberately don't use devm_request_irq @@ -858,6 +856,7 @@ int __uio_register_device(struct module *owner, goto err_request_irq; } =20 + info->uio_dev =3D idev; return 0; =20 err_request_irq: --=20 2.17.1