From patchwork Tue Dec 7 10:24:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 521944 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 559CCC4332F for ; Tue, 7 Dec 2021 10:25:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235140AbhLGK2i (ORCPT ); Tue, 7 Dec 2021 05:28:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235097AbhLGK20 (ORCPT ); Tue, 7 Dec 2021 05:28:26 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CD6D5C061D7E for ; Tue, 7 Dec 2021 02:24:55 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1muXeY-0003Nx-2D for stable@vger.kernel.org; Tue, 07 Dec 2021 11:24:54 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 1C9AD6BE8EC for ; Tue, 7 Dec 2021 10:24:47 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id 519806BE8A7; Tue, 7 Dec 2021 10:24:43 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id a5c88c68; Tue, 7 Dec 2021 10:24:26 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Vincent Mailhol , stable@vger.kernel.org, Matt Kline , Marc Kleine-Budde Subject: [PATCH net 4/9] can: m_can: m_can_read_fifo: fix memory leak in error branch Date: Tue, 7 Dec 2021 11:24:15 +0100 Message-Id: <20211207102420.120131-5-mkl@pengutronix.de> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211207102420.120131-1-mkl@pengutronix.de> References: <20211207102420.120131-1-mkl@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: stable@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vincent Mailhol In m_can_read_fifo(), if the second call to m_can_fifo_read() fails, the function jump to the out_fail label and returns without calling m_can_receive_skb(). This means that the skb previously allocated by alloc_can_skb() is not freed. In other terms, this is a memory leak. This patch adds a goto label to destroy the skb if an error occurs. Issue was found with GCC -fanalyzer, please follow the link below for details. Fixes: e39381770ec9 ("can: m_can: Disable IRQs on FIFO bus errors") Link: https://lore.kernel.org/all/20211107050755.70655-1-mailhol.vincent@wanadoo.fr Cc: stable@vger.kernel.org Cc: Matt Kline Signed-off-by: Vincent Mailhol Signed-off-by: Marc Kleine-Budde --- drivers/net/can/m_can/m_can.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 91be87c4f4d3..e330b4c121bf 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -517,7 +517,7 @@ static int m_can_read_fifo(struct net_device *dev, u32 rxfs) err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DATA, cf->data, DIV_ROUND_UP(cf->len, 4)); if (err) - goto out_fail; + goto out_free_skb; } /* acknowledge rx fifo 0 */ @@ -532,6 +532,8 @@ static int m_can_read_fifo(struct net_device *dev, u32 rxfs) return 0; +out_free_skb: + kfree_skb(skb); out_fail: netdev_err(dev, "FIFO read returned %d\n", err); return err;