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 43AFBC43334 for ; Tue, 19 Jul 2022 12:16:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239129AbiGSMQP (ORCPT ); Tue, 19 Jul 2022 08:16:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239386AbiGSMOg (ORCPT ); Tue, 19 Jul 2022 08:14:36 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B408D4C612; Tue, 19 Jul 2022 05:05:33 -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 ams.source.kernel.org (Postfix) with ESMTPS id 25A28B817AF; Tue, 19 Jul 2022 12:04:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6AF84C341C6; Tue, 19 Jul 2022 12:04:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658232267; bh=d+m4VWCUSsO3Sudpaqtn3IQBPQ5PF/wGQxEV8XVqCJo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zmPb+I4t0PFR9w4a0DlMugZcp9WuLhzyAf+fhoa6T7sPV73oLew3nz8fBoCnXXHKj 2AEABLVxJdAUFG5mTGaGm9/0cNCErYpof73h+5ybv6xTKTOwZ/cTJFny4aeMKjSOT2 mrA+CtR365POk2S8YnhimwlVa6QIuaYgZVkZY8ww= 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 5.4 71/71] can: m_can: m_can_tx_handler(): fix use after free of skb Date: Tue, 19 Jul 2022 13:54:34 +0200 Message-Id: <20220719114559.610828192@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220719114552.477018590@linuxfoundation.org> References: <20220719114552.477018590@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 @@ -1443,8 +1443,6 @@ static netdev_tx_t m_can_tx_handler(stru M_CAN_FIFO_DATA(i / 4), *(u32 *)(cf->data + i)); - can_put_echo_skb(skb, dev, 0); - if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) { cccr = m_can_read(cdev, M_CAN_CCCR); cccr &= ~(CCCR_CMR_MASK << CCCR_CMR_SHIFT); @@ -1461,6 +1459,9 @@ static netdev_tx_t m_can_tx_handler(stru m_can_write(cdev, M_CAN_CCCR, cccr); } m_can_write(cdev, M_CAN_TXBTIE, 0x1); + + can_put_echo_skb(skb, dev, 0); + m_can_write(cdev, M_CAN_TXBAR, 0x1); /* End of xmit function for version 3.0.x */ } else {