From: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> [ Upstream commit 39c71a5b8212f4b502d9a630c6706ac723abd422 ] In stm32_mdma_irq_handler(), chan is checked on line 1368. When chan is NULL, it is still used on line 1369: dev_err(chan2dev(chan), "MDMA channel not initialized\n"); Thus, a possible null-pointer dereference may occur. To fix this bug, "dev_dbg(mdma2dev(dmadev), ...)" is used instead. Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> Fixes: a4ffb13c8946 ("dmaengine: Add STM32 MDMA driver") Link: https://lore.kernel.org/r/20190729020849.17971-1-baijiaju1990@xxxxxxxxx Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/dma/stm32-mdma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c index 06dd1725375e5..8c3c3e5b812a8 100644 --- a/drivers/dma/stm32-mdma.c +++ b/drivers/dma/stm32-mdma.c @@ -1376,7 +1376,7 @@ static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid) chan = &dmadev->chan[id]; if (!chan) { - dev_err(chan2dev(chan), "MDMA channel not initialized\n"); + dev_dbg(mdma2dev(dmadev), "MDMA channel not initialized\n"); goto exit; } -- 2.20.1