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 4325AC433FE for ; Wed, 11 May 2022 20:37:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347854AbiEKUhn (ORCPT ); Wed, 11 May 2022 16:37:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347555AbiEKUhl (ORCPT ); Wed, 11 May 2022 16:37:41 -0400 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E9B1E2BB03; Wed, 11 May 2022 13:37:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1652301458; x=1683837458; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=ct8k43enuOkoow9AJvOHfRIKrB74EgiEykFuu2k4yEo=; b=OYQJXxRh/V5zLB+jxDp3B4M3PD4CC53OpW6LI9/cd4vRtN9fxUtH0PoF 4J9+X5BQaSC4ZdxYEO0KSihSXdtVN1vLw7i9RWVoHmiTYfhEUZdR643g4 vM6S3giX5rZgrLwwmqucVFTKHXB4tc3Rk4fp0vM2XrgAlGIzPceLWafuM KCjMYgDTqIpyc7ZbNSFX2yj2I4ylbj3bubdB+uGj2OUdMjgEo7Jb00oLB 5FrPkwDAN4bWCoa+xd8XKr/GX2DX5mNVp/rcm1M3Y0dTD0EzWRwLoQVwd LO2edNqEAyRBmbQkDMQJFODlqFtXq3aZfRsqHHRUCSZ0A6hE7R15oBVm/ Q==; X-IronPort-AV: E=Sophos;i="5.91,218,1647327600"; d="scan'208";a="95415885" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa6.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 11 May 2022 13:37:37 -0700 Received: from chn-vm-ex03.mchp-main.com (10.10.85.151) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.17; Wed, 11 May 2022 13:37:37 -0700 Received: from soft-dev3-1.microsemi.net (10.10.115.15) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server id 15.1.2375.17 via Frontend Transport; Wed, 11 May 2022 13:37:35 -0700 From: Horatiu Vultur To: , CC: , , , , , Horatiu Vultur , Dan Carpenter Subject: [PATCH net-next] net: lan966x: Fix use of pointer after being freed Date: Wed, 11 May 2022 22:40:59 +0200 Message-ID: <20220511204059.2689199-1-horatiu.vultur@microchip.com> X-Mailer: git-send-email 2.33.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The smatch found the following warning: drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c:736 lan966x_fdma_reload() warn: 'rx_dcbs' was already freed. This issue can happen when changing the MTU on one of the ports and once the RX buffers are allocated and then the TX buffer allocation fails. In that case the RX buffers should not be restore. This fix this issue such that the RX buffers will not be restored if the TX buffers failed to be allocated. Fixes: 2ea1cbac267e2a ("net: lan966x: Update FDMA to change MTU.") Reported-by: Dan Carpenter Signed-off-by: Horatiu Vultur --- drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c index 9e2a7323eaf0..6dea7f8c1481 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c @@ -729,11 +729,11 @@ static int lan966x_fdma_reload(struct lan966x *lan966x, int new_mtu) return err; restore: lan966x->rx.dma = rx_dma; - lan966x->tx.dma = tx_dma; + lan966x->rx.dcbs = rx_dcbs; lan966x_fdma_rx_start(&lan966x->rx); restore_tx: - lan966x->rx.dcbs = rx_dcbs; + lan966x->tx.dma = tx_dma; lan966x->tx.dcbs = tx_dcbs; lan966x->tx.dcbs_buf = tx_dcbs_buf; -- 2.33.0