4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pan Bian <bianpan2016@xxxxxxx> [ 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 <bianpan2016@xxxxxxx> Acked-by: Jakub Kicinski <kubakici@xxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/mediatek/mt7601u/mcu.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- 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 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(s }; 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 }; skb = mt7601u_mcu_msg_alloc(dev, &msg, sizeof(msg)); + if (!skb) + return -ENOMEM; return mt7601u_mcu_msg_send(dev, skb, CMD_CALIBRATION_OP, true); }