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: Julia Lawall , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 4.18 052/136] usb: wusbcore: security: cast sizeof to int for comparison Date: Mon, 17 Sep 2018 03:00:44 +0000 Message-ID: <20180917030006.245495-52-alexander.levin@microsoft.com> References: <20180917030006.245495-1-alexander.levin@microsoft.com> In-Reply-To: <20180917030006.245495-1-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: Julia Lawall [ Upstream commit d3ac5598c5010a8999978ebbcca3b1c6188ca36b ] Comparing an int to a size, which is unsigned, causes the int to become unsigned, giving the wrong result. usb_get_descriptor can return a negative error code. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // @@ int x; expression e,e1; identifier f; @@ *x =3D f(...); ... when !=3D x =3D e1 when !=3D if (x < 0 || ...) { ... return ...; } *x < sizeof(e) // Signed-off-by: Julia Lawall Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/wusbcore/security.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/wusbcore/security.c b/drivers/usb/wusbcore/securit= y.c index 33d2f5d7f33b..14ac8c98ac9e 100644 --- a/drivers/usb/wusbcore/security.c +++ b/drivers/usb/wusbcore/security.c @@ -217,7 +217,7 @@ int wusb_dev_sec_add(struct wusbhc *wusbhc, =20 result =3D usb_get_descriptor(usb_dev, USB_DT_SECURITY, 0, secd, sizeof(*secd)); - if (result < sizeof(*secd)) { + if (result < (int)sizeof(*secd)) { dev_err(dev, "Can't read security descriptor or " "not enough data: %d\n", result); goto out; --=20 2.17.1