This is a note to let you know that I've just added the patch titled dmaengine: at_hdmac: check return value of of_find_device_by_node() in at_dma_xlate() to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dmaengine-at_hdmac-check-return-value-of-of_find_dev.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 8b5a143fec3e825b96bc6174d958f38dd71bcd30 Author: Yu Kuai <yukuai3@xxxxxxxxxx> Date: Mon Aug 17 19:57:26 2020 +0800 dmaengine: at_hdmac: check return value of of_find_device_by_node() in at_dma_xlate() [ 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> diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 21ed0e20c5d91..cf3225a229890 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -1677,6 +1677,8 @@ 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);