From patchwork Sun Oct 31 03:24:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 12594925 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A10BC433F5 for ; Sun, 31 Oct 2021 03:24:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5D3866101B for ; Sun, 31 Oct 2021 03:24:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232125AbhJaD0z (ORCPT ); Sat, 30 Oct 2021 23:26:55 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:39752 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229887AbhJaD0y (ORCPT ); Sat, 30 Oct 2021 23:26:54 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 19V3OLd0052068; Sat, 30 Oct 2021 22:24:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1635650661; bh=OLW7UyDN/TPSK1agghVJpSkPj5olWRzqm2wSRsVuimU=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=gb8qyfzgkk5JehLsk6iXarMbCYFD45A2zPCZ4ohLEzbJckNncWQIKSUj9bJewWrua SyFgBntnZrWNPlYS59HgY2PtIKwSt3LrJoTIaVPcYqZUmZDNHWG5hnxRCM2ukcBODG 7Y7OBTUQyGj1kSSGidKJay6OKUnT825ngduEADqs= Received: from DLEE115.ent.ti.com (dlee115.ent.ti.com [157.170.170.26]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 19V3OLSC108843 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Sat, 30 Oct 2021 22:24:21 -0500 Received: from DLEE102.ent.ti.com (157.170.170.32) by DLEE115.ent.ti.com (157.170.170.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.14; Sat, 30 Oct 2021 22:24:21 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DLEE102.ent.ti.com (157.170.170.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.14 via Frontend Transport; Sat, 30 Oct 2021 22:24:21 -0500 Received: from a0393678-lt.ent.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 19V3OCwM084685; Sat, 30 Oct 2021 22:24:18 -0500 From: Kishon Vijay Abraham I To: Peter Ujfalusi , Vinod Koul CC: , , Vignesh Raghavendra , Kishon Vijay Abraham I Subject: [PATCH v4 2/2] dmaengine: ti: k3-udma: Set r/tchan or rflow to NULL if request fail Date: Sun, 31 Oct 2021 08:54:11 +0530 Message-ID: <20211031032411.27235-3-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211031032411.27235-1-kishon@ti.com> References: <20211031032411.27235-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org udma_get_*() checks if rchan/tchan/rflow is already allocated by checking if it has a NON NULL value. For the error cases, rchan/tchan/rflow will have error value and udma_get_*() considers this as already allocated (PASS) since the error values are NON NULL. This results in NULL pointer dereference error while de-referencing rchan/tchan/rflow. Reset the value of rchan/tchan/rflow to NULL if a channel request fails. CC: stable@vger.kernel.org Acked-by: Peter Ujfalusi Signed-off-by: Kishon Vijay Abraham I --- drivers/dma/ti/k3-udma.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c index 14ae28830871..041d8e32d630 100644 --- a/drivers/dma/ti/k3-udma.c +++ b/drivers/dma/ti/k3-udma.c @@ -1380,6 +1380,7 @@ static int bcdma_get_bchan(struct udma_chan *uc) static int udma_get_tchan(struct udma_chan *uc) { struct udma_dev *ud = uc->ud; + int ret; if (uc->tchan) { dev_dbg(ud->dev, "chan%d: already have tchan%d allocated\n", @@ -1394,8 +1395,11 @@ static int udma_get_tchan(struct udma_chan *uc) */ uc->tchan = __udma_reserve_tchan(ud, uc->config.channel_tpl, uc->config.mapped_channel_id); - if (IS_ERR(uc->tchan)) - return PTR_ERR(uc->tchan); + if (IS_ERR(uc->tchan)) { + ret = PTR_ERR(uc->tchan); + uc->tchan = NULL; + return ret; + } if (ud->tflow_cnt) { int tflow_id; @@ -1425,6 +1429,7 @@ static int udma_get_tchan(struct udma_chan *uc) static int udma_get_rchan(struct udma_chan *uc) { struct udma_dev *ud = uc->ud; + int ret; if (uc->rchan) { dev_dbg(ud->dev, "chan%d: already have rchan%d allocated\n", @@ -1439,8 +1444,13 @@ static int udma_get_rchan(struct udma_chan *uc) */ uc->rchan = __udma_reserve_rchan(ud, uc->config.channel_tpl, uc->config.mapped_channel_id); + if (IS_ERR(uc->rchan)) { + ret = PTR_ERR(uc->rchan); + uc->rchan = NULL; + return ret; + } - return PTR_ERR_OR_ZERO(uc->rchan); + return 0; } static int udma_get_chan_pair(struct udma_chan *uc) @@ -1494,6 +1504,7 @@ static int udma_get_chan_pair(struct udma_chan *uc) static int udma_get_rflow(struct udma_chan *uc, int flow_id) { struct udma_dev *ud = uc->ud; + int ret; if (!uc->rchan) { dev_err(ud->dev, "chan%d: does not have rchan??\n", uc->id); @@ -1507,8 +1518,13 @@ static int udma_get_rflow(struct udma_chan *uc, int flow_id) } uc->rflow = __udma_get_rflow(ud, flow_id); + if (IS_ERR(uc->rflow)) { + ret = PTR_ERR(uc->rflow); + uc->rflow = NULL; + return ret; + } - return PTR_ERR_OR_ZERO(uc->rflow); + return 0; } static void bcdma_put_bchan(struct udma_chan *uc)