[PATCH v2 2/5] dmaengine: fsl-edma: add safety check for 'srcid'

From: Frank Li <Frank.Li@nxp.com>
To: Vinod Koul <vkoul@kernel.org>, Rob Herring <robh@kernel.org>,
	 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	 Conor Dooley <conor+dt@kernel.org>, Peng Fan <peng.fan@nxp.com>
Cc: imx@lists.linux.dev, dmaengine@vger.kernel.org,
	 linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
	 Frank Li <Frank.Li@nxp.com>
Subject: [PATCH v2 2/5] dmaengine: fsl-edma: add safety check for 'srcid'
Date: Thu, 29 Feb 2024 15:58:08 -0500	[thread overview]
Message-ID: <20240229-8ulp_edma-v2-2-9d12f883c8f7@nxp.com> (raw)
In-Reply-To: <20240229-8ulp_edma-v2-0-9d12f883c8f7@nxp.com>

Ensure that 'srcid' is a non-zero value to avoid dtb passing invalid
'srcid' to the driver.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/fsl-edma-main.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/dma/fsl-edma-main.c b/drivers/dma/fsl-edma-main.c
index 0a6e0c4040274..2148a7f1ae843 100644
--- a/drivers/dma/fsl-edma-main.c
+++ b/drivers/dma/fsl-edma-main.c
@@ -115,6 +115,13 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
 				chan->device->privatecnt++;
 				fsl_chan = to_fsl_edma_chan(chan);
 				fsl_chan->srcid = dma_spec->args[1];
+
+				if (!fsl_chan->srcid) {
+					dev_err(&fsl_chan->pdev->dev, "Invalidate srcid %d\n",
+						fsl_chan->srcid);
+					return NULL;
+				}
+
 				fsl_edma_chan_mux(fsl_chan, fsl_chan->srcid,
 						true);
 				mutex_unlock(&fsl_edma->fsl_edma_mutex);

-- 
2.34.1

