From patchwork Tue Sep 11 15:21:45 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Ferre X-Patchwork-Id: 1438641 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork1.kernel.org (Postfix) with ESMTP id D3EC64025E for ; Tue, 11 Sep 2012 15:27:37 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TBSIM-0001LZ-5Y; Tue, 11 Sep 2012 15:22:34 +0000 Received: from eusmtp01.atmel.com ([212.144.249.243]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TBSIA-0001K6-Ly for linux-arm-kernel@lists.infradead.org; Tue, 11 Sep 2012 15:22:23 +0000 Received: from tenerife.corp.atmel.com (10.161.101.13) by eusmtp01.atmel.com (10.161.101.31) with Microsoft SMTP Server id 14.2.318.1; Tue, 11 Sep 2012 17:22:09 +0200 From: Nicolas Ferre To: Subject: [PATCH 2/2] dmaengine: at_hdmac: check that each sg data length is non-null Date: Tue, 11 Sep 2012 17:21:45 +0200 Message-ID: <4dd23d54172aedff69d4bb9be950cea18be9b848.1347375975.git.nicolas.ferre@atmel.com> X-Mailer: git-send-email 1.7.10 In-Reply-To: <77b1e7252fbc9a31e1ed8806e017f8bd8a4605e0.1347375975.git.nicolas.ferre@atmel.com> References: <77b1e7252fbc9a31e1ed8806e017f8bd8a4605e0.1347375975.git.nicolas.ferre@atmel.com> MIME-Version: 1.0 X-Spam-Note: CRM114 invocation failed X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record -0.3 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: nicolas.ferre@atmel.com, ludovic.desroches@atmel.com, plagnioj@jcrosoft.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Avoid the construction of a malformed DMA request sent to the DMA controller. Log message is for debug only because this condition is unlikely to append and may only trigger at driver development time. Signed-off-by: Nicolas Ferre Cc: Stable [2.6.31+] --- drivers/dma/at_hdmac.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 6c09e18..7ab6e26 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -689,6 +689,11 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, mem = sg_dma_address(sg); len = sg_dma_len(sg); + if (unlikely(!len)) { + dev_dbg(chan2dev(chan), + "prep_slave_sg: sg(%d) data length is zero\n", i); + goto err; + } mem_width = 2; if (unlikely(mem & 3 || len & 3)) mem_width = 0; @@ -724,6 +729,11 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, mem = sg_dma_address(sg); len = sg_dma_len(sg); + if (unlikely(!len)) { + dev_dbg(chan2dev(chan), + "prep_slave_sg: sg(%d) data length is zero\n", i); + goto err; + } mem_width = 2; if (unlikely(mem & 3 || len & 3)) mem_width = 0; @@ -757,6 +767,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, err_desc_get: dev_err(chan2dev(chan), "not enough descriptors available\n"); +err: atc_desc_put(atchan, first); return NULL; }