在 2023/1/18 2:18, Greg KH 写道:
On Fri, Nov 25, 2022 at 08:37:11AM +0000, Yuan Can wrote:
As the dma_alloc_coherent() may return NULL, the return value needs to be
checked to avoid NULL poineter dereference.
Fixes: 33aa8d45a4fe ("staging: emxx_udc: Add Emma Mobile USB Gadget driver")
Signed-off-by: Yuan Can <yuancan@xxxxxxxxxx>
---
drivers/staging/emxx_udc/emxx_udc.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/staging/emxx_udc/emxx_udc.c b/drivers/staging/emxx_udc/emxx_udc.c
index b6abd3770e81..3c0c9c5eb733 100644
--- a/drivers/staging/emxx_udc/emxx_udc.c
+++ b/drivers/staging/emxx_udc/emxx_udc.c
@@ -2594,6 +2594,10 @@ static int nbu2ss_ep_queue(struct usb_ep *_ep,
ep->virt_buf = dma_alloc_coherent(udc->dev, PAGE_SIZE,
&ep->phys_buf,
GFP_ATOMIC | GFP_DMA);
+ if (!ep->virt_buf) {
+ spin_unlock_irqrestore(&udc->lock, flags);
+ return -ENOMEM;
+ }
This should be checked in the if statment, not outside of it, right?
Yes, the next version will do the check just before the memcpy, thanks
for the suggestion.
--
Best regards,
Yuan Can
