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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 687B7C4332F for ; Fri, 1 Apr 2022 14:53:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349340AbiDAOzO (ORCPT ); Fri, 1 Apr 2022 10:55:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348146AbiDAOus (ORCPT ); Fri, 1 Apr 2022 10:50:48 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 281EA2B3D4B; Fri, 1 Apr 2022 07:41:56 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5B9A560A3C; Fri, 1 Apr 2022 14:41:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A65C5C3410F; Fri, 1 Apr 2022 14:41:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1648824084; bh=W0T1X+R3/oN9jNukhQbY+pp1TFXBcRxZNY5mbhYX01c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cX6p/uThF60bQj/ix1pzW0L1IRITkhPNb+N4aV9tehN20OE2WN5vEOyZHbq2it5Rt ZF2IGby8vAtGXd6Nyfwg0uFruXOlGT9DIWe2/4sEMuOBrEgI7dxb8aYwW4Nw/aqWfQ zs0zVrw7QPJJQJUlqDfX4ewZrrM9itnEQOdTAGZXk25x8Kxzlqe5i8ejCJL/+kdrqL pXkWFRK+hAshMgoFZC37TACVLqDZk2eWR6WguQmw4Ya+eXBBdZIuxQTuLmDmW9Nf43 Cw5DFKSxzF1Rv9/7vcMdgOXZQ2PV6rVCb6MC4BWF9aqAJNsiIwAi4w6uXIQIlNf7WL IvozMLuBhkRzA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vincent Mailhol , Marc Kleine-Budde , Sasha Levin , wg@grandegger.com, davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, linux-can@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 80/98] can: etas_es58x: es58x_fd_rx_event_msg(): initialize rx_event_msg before calling es58x_check_msg_len() Date: Fri, 1 Apr 2022 10:37:24 -0400 Message-Id: <20220401143742.1952163-80-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220401143742.1952163-1-sashal@kernel.org> References: <20220401143742.1952163-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Vincent Mailhol [ Upstream commit 7a8cd7c0ee823a1cc893ab3feaa23e4b602bfb9a ] Function es58x_fd_rx_event() invokes the es58x_check_msg_len() macro: | ret = es58x_check_msg_len(es58x_dev->dev, *rx_event_msg, msg_len); While doing so, it dereferences an uninitialized variable: *rx_event_msg. This is actually harmless because es58x_check_msg_len() only uses preprocessor macros (sizeof() and __stringify()) on *rx_event_msg. c.f. [1]. Nonetheless, this pattern is confusing so the lines are reordered to make sure that rx_event_msg is correctly initialized. This patch also fixes a false positive warning reported by cppcheck: | cppcheck possible warnings: (new ones prefixed by >>, may not be real problems) | | In file included from drivers/net/can/usb/etas_es58x/es58x_fd.c: | >> drivers/net/can/usb/etas_es58x/es58x_fd.c:174:8: warning: Uninitialized variable: rx_event_msg [uninitvar] | ret = es58x_check_msg_len(es58x_dev->dev, *rx_event_msg, msg_len); | ^ [1] https://elixir.bootlin.com/linux/v5.16/source/drivers/net/can/usb/etas_es58x/es58x_core.h#L467 Link: https://lore.kernel.org/all/20220306101302.708783-1-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin --- drivers/net/can/usb/etas_es58x/es58x_fd.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/can/usb/etas_es58x/es58x_fd.c b/drivers/net/can/usb/etas_es58x/es58x_fd.c index af042aa55f59..26bf4775e884 100644 --- a/drivers/net/can/usb/etas_es58x/es58x_fd.c +++ b/drivers/net/can/usb/etas_es58x/es58x_fd.c @@ -171,12 +171,11 @@ static int es58x_fd_rx_event_msg(struct net_device *netdev, const struct es58x_fd_rx_event_msg *rx_event_msg; int ret; + rx_event_msg = &es58x_fd_urb_cmd->rx_event_msg; ret = es58x_check_msg_len(es58x_dev->dev, *rx_event_msg, msg_len); if (ret) return ret; - rx_event_msg = &es58x_fd_urb_cmd->rx_event_msg; - return es58x_rx_err_msg(netdev, rx_event_msg->error_code, rx_event_msg->event_code, get_unaligned_le64(&rx_event_msg->timestamp)); -- 2.34.1