[PATCH AUTOSEL for 4.4 052/101] mt7601u: check return value of alloc_skb

[Sasha Levin]

From: Pan Bian <bianpan2...@163.com>

[ Upstream commit 5fb01e91daf84ad1e50edfcf63116ecbe31e7ba7 ]

Function alloc_skb() will return a NULL pointer if there is no enough
memory. However, in function mt7601u_mcu_msg_alloc(), its return value
is not validated before it is used. This patch fixes it.

Signed-off-by: Pan Bian <bianpan2...@163.com>
Acked-by: Jakub Kicinski <kubak...@wp.pl>
Signed-off-by: Kalle Valo <kv...@codeaurora.org>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
---
 drivers/net/wireless/mediatek/mt7601u/mcu.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt7601u/mcu.c 
b/drivers/net/wireless/mediatek/mt7601u/mcu.c
index fbb1986eda3c..686b1b5dd394 100644
--- a/drivers/net/wireless/mediatek/mt7601u/mcu.c
+++ b/drivers/net/wireless/mediatek/mt7601u/mcu.c
@@ -66,8 +66,10 @@ mt7601u_mcu_msg_alloc(struct mt7601u_dev *dev, const void 
*data, int len)
        WARN_ON(len % 4); /* if length is not divisible by 4 we need to pad */
 
        skb = alloc_skb(len + MT_DMA_HDR_LEN + 4, GFP_KERNEL);
-       skb_reserve(skb, MT_DMA_HDR_LEN);
-       memcpy(skb_put(skb, len), data, len);
+       if (skb) {
+               skb_reserve(skb, MT_DMA_HDR_LEN);
+               memcpy(skb_put(skb, len), data, len);
+       }
 
        return skb;
 }
@@ -170,6 +172,8 @@ static int mt7601u_mcu_function_select(struct mt7601u_dev 
*dev,
        };
 
        skb = mt7601u_mcu_msg_alloc(dev, &msg, sizeof(msg));
+       if (!skb)
+               return -ENOMEM;
        return mt7601u_mcu_msg_send(dev, skb, CMD_FUN_SET_OP, func == 5);
 }
 
@@ -205,6 +209,8 @@ mt7601u_mcu_calibrate(struct mt7601u_dev *dev, enum 
mcu_calibrate cal, u32 val)
        };
 
        skb = mt7601u_mcu_msg_alloc(dev, &msg, sizeof(msg));
+       if (!skb)
+               return -ENOMEM;
        return mt7601u_mcu_msg_send(dev, skb, CMD_CALIBRATION_OP, true);
 }
 
-- 
2.14.1