[PATCH net-next] NFC: digital: fix target leak after Type 1 Tag discovery

[Xia Yan]

digital_in_recv_sens_res() allocates a target for an NFC-A response.
For a Type 1 Tag, it calls digital_target_found() synchronously.
nfc_targets_found() copies the target into dev->targets.

On success, rc is zero and the callback skips kfree(target).
The original allocation is lost when the callback returns.
Each completed Type 1 Tag discovery leaks one struct nfc_target.

Free the target after digital_target_found() returns. Clear the pointer
to avoid freeing it again on the error path. Keep the target for other
tag types, whose discovery continues asynchronously.

Found during a code review of NFC-A target ownership.

Fixes: 2c66daecc409 ("NFC Digital: Add NFC-A technology support")
Signed-off-by: Xia Yan <yanxia@xxxxxxxxxxxxxxxxxxxx>
---
 net/nfc/digital_technology.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/nfc/digital_technology.c b/net/nfc/digital_technology.c
index ae6487c10a25..2d52e390cc67 100644
--- a/net/nfc/digital_technology.c
+++ b/net/nfc/digital_technology.c
@@ -510,10 +510,13 @@ static void digital_in_recv_sens_res(struct nfc_digital_dev *ddev, void *arg,
 		goto exit;
 	}
 
-	if (DIGITAL_SENS_RES_IS_T1T(target->sens_res))
+	if (DIGITAL_SENS_RES_IS_T1T(target->sens_res)) {
 		rc = digital_target_found(ddev, target, NFC_PROTO_JEWEL);
-	else
+		kfree(target);
+		target = NULL;
+	} else {
 		rc = digital_in_send_sdd_req(ddev, target);
+	}
 
 exit:
 	dev_kfree_skb(resp);