1 files changed, 39 insertions, 5 deletions

diff --git a/drivers/nfc/st21nfca/se.c b/drivers/nfc/st21nfca/se.c
index fd967a38a94a..8a96354796c7 100644
--- a/drivers/nfc/st21nfca/se.c
+++ b/drivers/nfc/st21nfca/se.c
@@ -247,12 +247,18 @@ int st21nfca_hci_se_io(struct nfc_hci_dev *hdev, u32 se_idx,
 					ST21NFCA_EVT_TRANSMIT_DATA,
 					apdu, apdu_length);
 	default:
+		/* Need to free cb_context here as at the moment we can't
+		 * clearly indicate to the caller if the callback function
+		 * would be called (and free it) or not. In both cases a
+		 * negative value may be returned to the caller.
+		 */
+		kfree(cb_context);
 		return -ENODEV;
 	}
 }
 EXPORT_SYMBOL(st21nfca_hci_se_io);
 
-static void st21nfca_se_wt_timeout(struct timer_list *t)
+static void st21nfca_se_wt_work(struct work_struct *work)
 {
 	/*
 	 * No answer from the secure element
@@ -265,8 +271,9 @@ static void st21nfca_se_wt_timeout(struct timer_list *t)
 	 */
 	/* hardware reset managed through VCC_UICC_OUT power supply */
 	u8 param = 0x01;
-	struct st21nfca_hci_info *info = from_timer(info, t,
-						    se_info.bwi_timer);
+	struct st21nfca_hci_info *info = container_of(work,
+						struct st21nfca_hci_info,
+						se_info.timeout_work);
 
 	pr_debug("\n");
 
@@ -284,6 +291,13 @@ static void st21nfca_se_wt_timeout(struct timer_list *t)
 	info->se_info.cb(info->se_info.cb_context, NULL, 0, -ETIME);
 }
 
+static void st21nfca_se_wt_timeout(struct timer_list *t)
+{
+	struct st21nfca_hci_info *info = from_timer(info, t, se_info.bwi_timer);
+
+	schedule_work(&info->se_info.timeout_work);
+}
+
 static void st21nfca_se_activation_timeout(struct timer_list *t)
 {
 	struct st21nfca_hci_info *info = from_timer(info, t,
@@ -322,7 +336,7 @@ int st21nfca_connectivity_event_received(struct nfc_hci_dev *hdev, u8 host,
 		 * AID		81	5 to 16
 		 * PARAMETERS	82	0 to 255
 		 */
-		if (skb->len < NFC_MIN_AID_LENGTH + 2 &&
+		if (skb->len < NFC_MIN_AID_LENGTH + 2 ||
 		    skb->data[0] != NFC_EVT_TRANSACTION_AID_TAG)
 			return -EPROTO;
 
@@ -332,15 +346,32 @@ int st21nfca_connectivity_event_received(struct nfc_hci_dev *hdev, u8 host,
 			return -ENOMEM;
 
 		transaction->aid_len = skb->data[1];
+
+		/* Checking if the length of the AID is valid */
+		if (transaction->aid_len > sizeof(transaction->aid)) {
+			devm_kfree(dev, transaction);
+			return -EINVAL;
+		}
+
 		memcpy(transaction->aid, &skb->data[2],
 		       transaction->aid_len);
 
 		/* Check next byte is PARAMETERS tag (82) */
 		if (skb->data[transaction->aid_len + 2] !=
-		    NFC_EVT_TRANSACTION_PARAMS_TAG)
+		    NFC_EVT_TRANSACTION_PARAMS_TAG) {
+			devm_kfree(dev, transaction);
 			return -EPROTO;
+		}
 
 		transaction->params_len = skb->data[transaction->aid_len + 3];
+
+		/* Total size is allocated (skb->len - 2) minus fixed array members */
+		if (transaction->params_len > ((skb->len - 2) -
+		    sizeof(struct nfc_evt_transaction))) {
+			devm_kfree(dev, transaction);
+			return -EINVAL;
+		}
+
 		memcpy(transaction->params, skb->data +
 		       transaction->aid_len + 4, transaction->params_len);
 
@@ -366,6 +397,7 @@ int st21nfca_apdu_reader_event_received(struct nfc_hci_dev *hdev,
 	switch (event) {
 	case ST21NFCA_EVT_TRANSMIT_DATA:
 		del_timer_sync(&info->se_info.bwi_timer);
+		cancel_work_sync(&info->se_info.timeout_work);
 		info->se_info.bwi_active = false;
 		r = nfc_hci_send_event(hdev, ST21NFCA_DEVICE_MGNT_GATE,
 				ST21NFCA_EVT_SE_END_OF_APDU_TRANSFER, NULL, 0);
@@ -395,6 +427,7 @@ void st21nfca_se_init(struct nfc_hci_dev *hdev)
 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 
 	init_completion(&info->se_info.req_completion);
+	INIT_WORK(&info->se_info.timeout_work, st21nfca_se_wt_work);
 	/* initialize timers */
 	timer_setup(&info->se_info.bwi_timer, st21nfca_se_wt_timeout, 0);
 	info->se_info.bwi_active = false;
@@ -422,6 +455,7 @@ void st21nfca_se_deinit(struct nfc_hci_dev *hdev)
 	if (info->se_info.se_active)
 		del_timer_sync(&info->se_info.se_active_timer);
 
+	cancel_work_sync(&info->se_info.timeout_work);
 	info->se_info.bwi_active = false;
 	info->se_info.se_active = false;
 }