From patchwork Sun Oct 31 03:24:10 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: 12594923 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 52D8DC433FE for ; Sun, 31 Oct 2021 03:24:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31E136101B for ; Sun, 31 Oct 2021 03:24:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232110AbhJaD0y (ORCPT ); Sat, 30 Oct 2021 23:26:54 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:39722 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232098AbhJaD0x (ORCPT ); Sat, 30 Oct 2021 23:26:53 -0400 Received: from lelv0265.itg.ti.com ([10.180.67.224]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 19V3OJuU052058; Sat, 30 Oct 2021 22:24:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1635650659; bh=U9AvzxfTLAIX9yJbLJYovtXIrnAxAtlf7rpHUVub81w=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=yFXf1SMgsR66caCWS+AepEvWcXmFWMmcnaizku+mu2IiXAGQIL7ge3OUPxhpNFsoq RLdcz0uQN8irFg3k0vilpEDeiwa5QcQqeQV6SP8H2Vaz44kUgACAe1hAQFP9oc7t/K 5k/IKCUeOJCRHEyPnPd7QH/Ixohsj73vZXEvkLhk= Received: from DFLE103.ent.ti.com (dfle103.ent.ti.com [10.64.6.24]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 19V3OJUJ033546 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Sat, 30 Oct 2021 22:24:19 -0500 Received: from DFLE113.ent.ti.com (10.64.6.34) by DFLE103.ent.ti.com (10.64.6.24) 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 22:24:18 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DFLE113.ent.ti.com (10.64.6.34) 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 22:24:18 -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 19V3OCwL084685; Sat, 30 Oct 2021 22:24:15 -0500 From: Kishon Vijay Abraham I To: Peter Ujfalusi , Vinod Koul CC: , , Vignesh Raghavendra , Kishon Vijay Abraham I Subject: [PATCH v4 1/2] dmaengine: ti: k3-udma: Set bchan to NULL if a channel request fail Date: Sun, 31 Oct 2021 08:54:10 +0530 Message-ID: <20211031032411.27235-2-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 bcdma_get_*() checks if bchan is already allocated by checking if it has a NON NULL value. For the error cases, bchan will have error value and bcdma_get_*() considers this as already allocated (PASS) since the error values are NON NULL. This results in NULL pointer dereference error while de-referencing bchan. Reset the value of bchan 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 | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c index a35858610780..14ae28830871 100644 --- a/drivers/dma/ti/k3-udma.c +++ b/drivers/dma/ti/k3-udma.c @@ -1348,6 +1348,7 @@ static int bcdma_get_bchan(struct udma_chan *uc) { struct udma_dev *ud = uc->ud; enum udma_tp_level tpl; + int ret; if (uc->bchan) { dev_dbg(ud->dev, "chan%d: already have bchan%d allocated\n", @@ -1365,8 +1366,11 @@ static int bcdma_get_bchan(struct udma_chan *uc) tpl = ud->bchan_tpl.levels - 1; uc->bchan = __udma_reserve_bchan(ud, tpl, -1); - if (IS_ERR(uc->bchan)) - return PTR_ERR(uc->bchan); + if (IS_ERR(uc->bchan)) { + ret = PTR_ERR(uc->bchan); + uc->bchan = NULL; + return ret; + } uc->tchan = uc->bchan;