[PATCH 4.9 21/50] NFC: digital: fix possible memory leak in digital_in_send_sdd_req()

[Greg Kroah-Hartman]

From: Ziyang Xuan <william.xuanziyang@xxxxxxxxxx>

commit 291c932fc3692e4d211a445ba8aa35663831bac7 upstream.

'skb' is allocated in digital_in_send_sdd_req(), but not free when
digital_in_send_cmd() failed, which will cause memory leak. Fix it
by freeing 'skb' if digital_in_send_cmd() return failed.

Fixes: 2c66daecc409 ("NFC Digital: Add NFC-A technology support")
Signed-off-by: Ziyang Xuan <william.xuanziyang@xxxxxxxxxx>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/nfc/digital_technology.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/net/nfc/digital_technology.c
+++ b/net/nfc/digital_technology.c
@@ -473,8 +473,12 @@ static int digital_in_send_sdd_req(struc
 	*skb_put(skb, sizeof(u8)) = sel_cmd;
 	*skb_put(skb, sizeof(u8)) = DIGITAL_SDD_REQ_SEL_PAR;
 
-	return digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sdd_res,
-				   target);
+	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sdd_res,
+				 target);
+	if (rc)
+		kfree_skb(skb);
+
+	return rc;
 }
 
 static void digital_in_recv_sens_res(struct nfc_digital_dev *ddev, void *arg,