Commit d4d63059 authored by Johan Hovold's avatar Johan Hovold Committed by Vinod Koul
Browse files

dmaengine: lpc18xx-dmamux: fix device leak on route allocation 



Make sure to drop the reference taken when looking up the DMA mux
platform device during route allocation.

Note that holding a reference to a device does not prevent its driver
data from going away so there is no point in keeping the reference.

Fixes: e5f4ae84 ("dmaengine: add driver for lpc18xx dmamux")
Cc: stable@vger.kernel.org	# 4.3
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
Reviewed-by: default avatarVladimir Zapolskiy <vz@mleia.com>
Link: https://patch.msgid.link/20251117161258.10679-8-johan@kernel.org


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 799900f0

drivers/dma/lpc18xx-dmamux.c

+14 −5
Original line number Diff line number Diff line
@@ -57,30 +57,31 @@ static void *lpc18xx_dmamux_reserve(struct of_phandle_args *dma_spec, 
	struct lpc18xx_dmamux_data *dmamux = platform_get_drvdata(pdev);

	unsigned long flags;

	unsigned mux;

	int ret = -EINVAL;



	if (dma_spec->args_count != 3) {

		dev_err(&pdev->dev, "invalid number of dma mux args\n");

		return ERR_PTR(-EINVAL);

		goto err_put_pdev;

	}



	mux = dma_spec->args[0];

	if (mux >= dmamux->dma_master_requests) {

		dev_err(&pdev->dev, "invalid mux number: %d\n",

			dma_spec->args[0]);

		return ERR_PTR(-EINVAL);

		goto err_put_pdev;

	}



	if (dma_spec->args[1] > LPC18XX_DMAMUX_MAX_VAL) {

		dev_err(&pdev->dev, "invalid dma mux value: %d\n",

			dma_spec->args[1]);

		return ERR_PTR(-EINVAL);

		goto err_put_pdev;

	}



	/* The of_node_put() will be done in the core for the node */

	dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0);

	if (!dma_spec->np) {

		dev_err(&pdev->dev, "can't get dma master\n");

		return ERR_PTR(-EINVAL);

		goto err_put_pdev;

	}



	spin_lock_irqsave(&dmamux->lock, flags);
@@ -89,7 +90,8 @@ static void *lpc18xx_dmamux_reserve(struct of_phandle_args *dma_spec, 
		dev_err(&pdev->dev, "dma request %u busy with %u.%u\n",

			mux, mux, dmamux->muxes[mux].value);

		of_node_put(dma_spec->np);

		return ERR_PTR(-EBUSY);

		ret = -EBUSY;

		goto err_put_pdev;

	}



	dmamux->muxes[mux].busy = true;
@@ -106,7 +108,14 @@ static void *lpc18xx_dmamux_reserve(struct of_phandle_args *dma_spec, 
	dev_dbg(&pdev->dev, "mapping dmamux %u.%u to dma request %u\n", mux,

		dmamux->muxes[mux].value, mux);



	put_device(&pdev->dev);



	return &dmamux->muxes[mux];



err_put_pdev:

	put_device(&pdev->dev);



	return ERR_PTR(ret);

}



static int lpc18xx_dmamux_probe(struct platform_device *pdev)