[PATCH net-next] nfc: nci: fix possible NULL pointer dereference in send_acknowledge()

[Krzysztof Kozlowski]

Handle memory allocation failure from nci_skb_alloc() (calling
alloc_skb()) to avoid possible NULL pointer dereference.

Reported-by: 黄思聪 <huangsicong@xxxxxxxxx>
Fixes: 391d8a2da787 ("NFC: Add NCI over SPI receive")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
---
 net/nfc/nci/spi.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/nfc/nci/spi.c b/net/nfc/nci/spi.c
index 0935527d1d12..b68150c971d0 100644
--- a/net/nfc/nci/spi.c
+++ b/net/nfc/nci/spi.c
@@ -151,6 +151,8 @@ static int send_acknowledge(struct nci_spi *nspi, u8 acknowledge)
 	int ret;
 
 	skb = nci_skb_alloc(nspi->ndev, 0, GFP_KERNEL);
+	if (!skb)
+		return -ENOMEM;
 
 	/* add the NCI SPI header to the start of the buffer */
 	hdr = skb_push(skb, NCI_SPI_HDR_LEN);
-- 
2.34.1