From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8810BC2BA2B for ; Sat, 11 Apr 2020 12:15:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5DC3C20644 for ; Sat, 11 Apr 2020 12:15:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586607341; bh=GDBkdFyQwNJy3s7hikLvymUoDDGW7i4bveuG7EFg1oA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=s3ZBYP4Q58sYBJyooD16bpW7cy2BGbbZonW+02Lq72enBufQU9MfCseN0rFdjhehc ARU/QceEV1WNgENjAtH/s4b0CKkviNnS/bTLWxH/g2HCqt9NYhM6sJJc6dw67w/zBW 9fTGWCPiq2hle3C5N+x7jTo5bd1/8BdyKrpVGq74= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727547AbgDKMPj (ORCPT ); Sat, 11 Apr 2020 08:15:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:49590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728121AbgDKMPh (ORCPT ); Sat, 11 Apr 2020 08:15:37 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A88C020644; Sat, 11 Apr 2020 12:15:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586607337; bh=GDBkdFyQwNJy3s7hikLvymUoDDGW7i4bveuG7EFg1oA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RAoNy7kQ3vIl7pO8qEiQt0rezIPfKGBgLNDH9vRo5kvhjrG6FbQW3lGRMYWCItZCN 092lpeSkQ8G9yuD+lFzO/im9PMwBQDAFTq3fPoLuz16+1z6m27Xay5x6nHlao/FG8S 5ijyIYI+ycnKBctWkvWgBkI0IXJbQOgP4BIDIEOY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Richard Palethorpe , Kees Cook , linux-can@vger.kernel.org, netdev@vger.kernel.org, security@kernel.org, wg@grandegger.com, mkl@pengutronix.de, davem@davemloft.net Subject: [PATCH 4.19 33/54] slcan: Dont transmit uninitialized stack data in padding Date: Sat, 11 Apr 2020 14:09:15 +0200 Message-Id: <20200411115511.772234226@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200411115508.284500414@linuxfoundation.org> References: <20200411115508.284500414@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Richard Palethorpe [ Upstream commit b9258a2cece4ec1f020715fe3554bc2e360f6264 ] struct can_frame contains some padding which is not explicitly zeroed in slc_bump. This uninitialized data will then be transmitted if the stack initialization hardening feature is not enabled (CONFIG_INIT_STACK_ALL). This commit just zeroes the whole struct including the padding. Signed-off-by: Richard Palethorpe Fixes: a1044e36e457 ("can: add slcan driver for serial/USB-serial CAN adapters") Reviewed-by: Kees Cook Cc: linux-can@vger.kernel.org Cc: netdev@vger.kernel.org Cc: security@kernel.org Cc: wg@grandegger.com Cc: mkl@pengutronix.de Cc: davem@davemloft.net Acked-by: Marc Kleine-Budde Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/slcan.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/net/can/slcan.c +++ b/drivers/net/can/slcan.c @@ -147,7 +147,7 @@ static void slc_bump(struct slcan *sl) u32 tmpid; char *cmd = sl->rbuff; - cf.can_id = 0; + memset(&cf, 0, sizeof(cf)); switch (*cmd) { case 'r': @@ -186,8 +186,6 @@ static void slc_bump(struct slcan *sl) else return; - *(u64 *) (&cf.data) = 0; /* clear payload */ - /* RTR frames may have a dlc > 0 but they never have any data bytes */ if (!(cf.can_id & CAN_RTR_FLAG)) { for (i = 0; i < cf.can_dlc; i++) {