[PATCH] dmaengine: dw: dmamux: Add NULL check in rzn1_dmamux_route_allocate()
From: Charles Han <hidden>
Date: 2025-06-16 10:48:15
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Subsystem:
dma generic offload engine subsystem, synopsys designware dmac driver, the rest · Maintainers:
Vinod Koul, Viresh Kumar, Linus Torvalds
The function of_find_device_by_node() may return NULL if the device
node cannot be found or CONFIG_OF is not defined, dereferencing
it without NULL check may lead to NULL dereference.
Add a check to verify whether the return value is NULL.
Fixes: 134d9c52fca2 ("dmaengine: dw: dmamux: Introduce RZN1 DMA router support")
Signed-off-by: Charles Han <redacted>
---
drivers/dma/dw/rzn1-dmamux.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/dw/rzn1-dmamux.c b/drivers/dma/dw/rzn1-dmamux.c
index 4fb8508419db..a21623d98e41 100644
--- a/drivers/dma/dw/rzn1-dmamux.c
+++ b/drivers/dma/dw/rzn1-dmamux.c@@ -41,13 +41,19 @@ static void rzn1_dmamux_free(struct device *dev, void *route_data) static void *rzn1_dmamux_route_allocate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { - struct platform_device *pdev = of_find_device_by_node(ofdma->of_node); - struct rzn1_dmamux_data *dmamux = platform_get_drvdata(pdev); + struct platform_device *pdev; + struct rzn1_dmamux_data *dmamux; struct rzn1_dmamux_map *map; unsigned int dmac_idx, chan, val; u32 mask; int ret; + pdev = of_find_device_by_node(ofdma->of_node); + if (!pdev) + return ERR_PTR(-ENODEV); + + dmamux = platform_get_drvdata(pdev); + if (dma_spec->args_count != RNZ1_DMAMUX_NCELLS) return ERR_PTR(-EINVAL);
--
2.43.0