[PATCH v2] usb: gadget: aspeed_udc: Add check for dma_alloc_coherent

[Jiasheng Jiang]

Add the check for the return value of dma_alloc_coherent
in order to avoid NULL pointer dereference.

Fixes: 055276c13205 ("usb: gadget: add Aspeed ast2600 udc driver")
Signed-off-by: Jiasheng Jiang <jiash...@iscas.ac.cn>
---
Changelog:

v1 -> v2:

1. Add "goto err;" when allocation fails.
---
 drivers/usb/gadget/udc/aspeed_udc.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/gadget/udc/aspeed_udc.c 
b/drivers/usb/gadget/udc/aspeed_udc.c
index 01968e2167f9..7dc2457c7460 100644
--- a/drivers/usb/gadget/udc/aspeed_udc.c
+++ b/drivers/usb/gadget/udc/aspeed_udc.c
@@ -1516,6 +1516,10 @@ static int ast_udc_probe(struct platform_device *pdev)
                                          AST_UDC_EP_DMA_SIZE *
                                          AST_UDC_NUM_ENDPOINTS,
                                          &udc->ep0_buf_dma, GFP_KERNEL);
+       if (!udc->ep0_buf) {
+               rc = -ENOMEM;
+               goto err;
+       }
 
        udc->gadget.speed = USB_SPEED_UNKNOWN;
        udc->gadget.max_speed = USB_SPEED_HIGH;
-- 
2.25.1