Commit 71d24f45 authored Jul 29, 2019 by Jia-Ju Bai Committed by Greg Kroah-Hartman Sep 06, 2019

dmaengine: stm32-mdma: Fix a possible null-pointer dereference in stm32_mdma_irq_handler()



[ 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@gmail.com>
Fixes: a4ffb13c ("dmaengine: Add STM32 MDMA driver")
Link: https://lore.kernel.org/r/20190729020849.17971-1-baijiaju1990@gmail.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 377ebe61

drivers/dma/stm32-mdma.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -1376,7 +1376,7 @@ static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid)

	chan = &dmadev->chan[id];		chan = &dmadev->chan[id];
	if (!chan) {		if (!chan) {
	dev_err(chan2dev(chan), "MDMA channel not initialized\n");		dev_dbg(mdma2dev(dmadev), "MDMA channel not initialized\n");
	goto exit;		goto exit;
	}		}