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 BEB7CC43334 for ; Tue, 19 Jul 2022 12:03:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237894AbiGSMDE (ORCPT ); Tue, 19 Jul 2022 08:03:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238021AbiGSMCd (ORCPT ); Tue, 19 Jul 2022 08:02:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0CED64B0F8; Tue, 19 Jul 2022 04:59:05 -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 0456661647; Tue, 19 Jul 2022 11:59:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C516FC341C6; Tue, 19 Jul 2022 11:59:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658231944; bh=UcDZ58eCiejyh3LpsXs/Q/VB86xvoENvhAWfgMJHGLc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TiFbUVY6gOc+UxsaF5gJiZwOFL/phgnpSav2iDVZugfDBOI+O/bF5XigyMQM48Ch0 tTZFdU51FwqRr8gBR5s9tUF7Kz6wP2+nU83sQRXBFB6ozlyFq8AkpswkOEJdCxeH7V SyqVjpOoFskCnHaPcQ5BDnx0k9aIHlMPlhV02/Ks= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hangyu Hua , Marc Kleine-Budde , Sudip Mukherjee Subject: [PATCH 4.14 43/43] can: m_can: m_can_tx_handler(): fix use after free of skb Date: Tue, 19 Jul 2022 13:54:14 +0200 Message-Id: <20220719114525.587310460@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220719114521.868169025@linuxfoundation.org> References: <20220719114521.868169025@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marc Kleine-Budde commit 2e8e79c416aae1de224c0f1860f2e3350fa171f8 upstream. can_put_echo_skb() will clone skb then free the skb. Move the can_put_echo_skb() for the m_can version 3.0.x directly before the start of the xmit in hardware, similar to the 3.1.x branch. Fixes: 80646733f11c ("can: m_can: update to support CAN FD features") Link: https://lore.kernel.org/all/20220317081305.739554-1-mkl@pengutronix.de Cc: stable@vger.kernel.org Reported-by: Hangyu Hua Signed-off-by: Marc Kleine-Budde [sudip: adjust context] Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/m_can/m_can.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1420,8 +1420,6 @@ static netdev_tx_t m_can_start_xmit(stru M_CAN_FIFO_DATA(i / 4), *(u32 *)(cf->data + i)); - can_put_echo_skb(skb, dev, 0); - if (priv->can.ctrlmode & CAN_CTRLMODE_FD) { cccr = m_can_read(priv, M_CAN_CCCR); cccr &= ~(CCCR_CMR_MASK << CCCR_CMR_SHIFT); @@ -1438,6 +1436,9 @@ static netdev_tx_t m_can_start_xmit(stru m_can_write(priv, M_CAN_CCCR, cccr); } m_can_write(priv, M_CAN_TXBTIE, 0x1); + + can_put_echo_skb(skb, dev, 0); + m_can_write(priv, M_CAN_TXBAR, 0x1); /* End of xmit function for version 3.0.x */ } else {