diff mbox series

[1/3] dmaengine: stm32-mdma: abort resume if no ongoing transfer

Message ID 20231004163531.2864160-1-amelie.delaunay@foss.st.com (mailing list archive)
State Accepted
Commit 81337b9a72dc58a5fa0ae8a042e8cb59f9bdec4a
Headers show
Series [1/3] dmaengine: stm32-mdma: abort resume if no ongoing transfer | expand

Commit Message

Amelie Delaunay Oct. 4, 2023, 4:35 p.m. UTC
chan->desc can be null, if transfer is terminated when resume is called,
leading to a NULL pointer when retrieving the hwdesc.
To avoid this case, check that chan->desc is not null and channel is
disabled (transfer previously paused or terminated).

Fixes: a4ffb13c8946 ("dmaengine: Add STM32 MDMA driver")
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Cc: stable@vger.kernel.org
---
 drivers/dma/stm32-mdma.c | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Vinod Koul Oct. 9, 2023, 6:12 a.m. UTC | #1
On Wed, 04 Oct 2023 18:35:28 +0200, Amelie Delaunay wrote:
> chan->desc can be null, if transfer is terminated when resume is called,
> leading to a NULL pointer when retrieving the hwdesc.
> To avoid this case, check that chan->desc is not null and channel is
> disabled (transfer previously paused or terminated).
> 
> 

Applied, thanks!

[1/3] dmaengine: stm32-mdma: abort resume if no ongoing transfer
      commit: 81337b9a72dc58a5fa0ae8a042e8cb59f9bdec4a
[2/3] dmaengine: stm32-mdma: use Link Address Register to compute residue
      commit: a4b306eb83579c07b63dc65cd5bae53b7b4019d0
[3/3] dmaengine: stm32-mdma: set in_flight_bytes in case CRQA flag is set
      commit: 584970421725b7805db84714b857851fdf7203a9

Best regards,
diff mbox series

Patch

diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
index 0de234022c6d..cc6f4b00091f 100644
--- a/drivers/dma/stm32-mdma.c
+++ b/drivers/dma/stm32-mdma.c
@@ -1236,6 +1236,10 @@  static int stm32_mdma_resume(struct dma_chan *c)
 	unsigned long flags;
 	u32 status, reg;
 
+	/* Transfer can be terminated */
+	if (!chan->desc || (stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)) & STM32_MDMA_CCR_EN))
+		return -EPERM;
+
 	hwdesc = chan->desc->node[chan->curr_hwdesc].hwdesc;
 
 	spin_lock_irqsave(&chan->vchan.lock, flags);