From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Yuan Can <yuancan@huawei.com>, Simon Horman <horms@verge.net.au>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Sasha Levin <sashal@kernel.org>, drv@mailo.com,
        linux-staging@lists.linux.dev
Subject: [PATCH AUTOSEL 6.2 14/64] staging: emxx_udc: Add checks for dma_alloc_coherent()
Date:   Fri,  3 Mar 2023 16:40:16 -0500
Message-Id: <20230303214106.1446460-14-sashal@kernel.org>
In-Reply-To: <20230303214106.1446460-1-sashal@kernel.org>
References: <20230303214106.1446460-1-sashal@kernel.org>
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From: Yuan Can <yuancan@huawei.com>

[ 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@huawei.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Link: https://lore.kernel.org/r/20230119083119.16956-1-yuancan@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 b4e19174bef2e..f9765841c4aa3 100644
--- a/drivers/staging/emxx_udc/emxx_udc.c
+++ b/drivers/staging/emxx_udc/emxx_udc.c
@@ -2587,10 +2587,15 @@ 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