[PATCH AUTOSEL 5.10 07/30] staging: emxx_udc: Add checks for dma_alloc_coherent()

From: Sasha Levin
Date: Fri Mar 03 2023 - 17:54:59 EST


From: Yuan Can <yuancan@xxxxxxxxxx>

[ Upstream commit f6510a93cfd8c6c79b4dda0f2967cdc6df42eff4 ]

As the dma_alloc_coherent may return NULL, the return value needs to be
checked to avoid NULL poineter dereference.

Signed-off-by: Yuan Can <yuancan@xxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230119083119.16956-1-yuancan@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/staging/emxx_udc/emxx_udc.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/emxx_udc/emxx_udc.c b/drivers/staging/emxx_udc/emxx_udc.c
index 3897f8e8f5e0d..6870a33d4ccf3 100644
--- a/drivers/staging/emxx_udc/emxx_udc.c
+++ b/drivers/staging/emxx_udc/emxx_udc.c
@@ -2591,10 +2591,15 @@ static int nbu2ss_ep_queue(struct usb_ep *_ep,
req->unaligned = false;

if (req->unaligned) {
- if (!ep->virt_buf)
+ if (!ep->virt_buf) {
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;
+ }
+ }
if (ep->epnum > 0) {
if (ep->direct == USB_DIR_IN)
memcpy(ep->virt_buf, req->req.buf,
--
2.39.2