From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-bn3nam01on0094.outbound.protection.outlook.com ([104.47.33.94]:25184 "EHLO NAM01-BN3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1031932AbeCAPYS (ORCPT ); Thu, 1 Mar 2018 10:24:18 -0500 From: Sasha Levin To: "stable@vger.kernel.org" , "stable-commits@vger.kernel.org" CC: Arnd Bergmann , "David S . Miller" , Sasha Levin Subject: [added to the 4.1 stable tree] isdn: kcapi: avoid uninitialized data Date: Thu, 1 Mar 2018 15:22:51 +0000 Message-ID: <20180301152116.1486-40-alexander.levin@microsoft.com> References: <20180301152116.1486-1-alexander.levin@microsoft.com> In-Reply-To: <20180301152116.1486-1-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: stable-owner@vger.kernel.org List-ID: From: Arnd Bergmann This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D [ Upstream commit af109a2cf6a9a6271fa420ae2d64d72d86c92b7d ] gcc-7 points out that the AVMB1_ADDCARD ioctl results in an unintialized value ending up in the cardnr parameter: drivers/isdn/capi/kcapi.c: In function 'old_capi_manufacturer': drivers/isdn/capi/kcapi.c:1042:24: error: 'cdef.cardnr' may be used uniniti= alized in this function [-Werror=3Dmaybe-uninitialized] cparams.cardnr =3D cdef.cardnr; This has been broken since before the start of the git history, so either the value is not used for anything important, or the ioctl command doesn't get called in practice. Setting the cardnr to zero avoids the warning and makes sure we have consistent behavior. Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/isdn/capi/kcapi.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/isdn/capi/kcapi.c b/drivers/isdn/capi/kcapi.c index 823f6985b260..dd7e38ac29bd 100644 --- a/drivers/isdn/capi/kcapi.c +++ b/drivers/isdn/capi/kcapi.c @@ -1032,6 +1032,7 @@ static int old_capi_manufacturer(unsigned int cmd, vo= id __user *data) sizeof(avmb1_carddef)))) return -EFAULT; cdef.cardtype =3D AVM_CARDTYPE_B1; + cdef.cardnr =3D 0; } else { if ((retval =3D copy_from_user(&cdef, data, sizeof(avmb1_extcarddef)))) --=20 2.14.1