From: Yu Kuai <yukuai3@xxxxxxxxxx> [ Upstream commit 0cef8e2c5a07d482ec907249dbd6687e8697677f ] The reurn value of of_find_device_by_node() is not checked, thus null pointer dereference will be triggered if of_find_device_by_node() failed. Fixes: bbe89c8e3d59 ("at_hdmac: move to generic DMA binding") Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> Link: https://lore.kernel.org/r/20200817115728.1706719-2-yukuai3@xxxxxxxxxx Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/dma/at_hdmac.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 73a20780744bf..22c1c507055a3 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -1650,6 +1650,8 @@ static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec, return NULL; dmac_pdev = of_find_device_by_node(dma_spec->np); + if (!dmac_pdev) + return NULL; dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); -- 2.25.1