[PATCH 5.4 404/411] nfc: st21nfca: fix incorrect validating logic in EVT_TRANSACTION

Greg Kroah-Hartman
2022-06-13T11:55:43Z

From: Martin Faltesek <mfaltesek@google.com>

commit 77e5fe8f176a525523ae091d6fd0fbb8834c156d upstream.

The first validation check for EVT_TRANSACTION has two different checks
tied together with logical AND. One is a check for minimum packet length,
and the other is for a valid aid_tag. If either condition is true (fails),
then an error should be triggered. The fix is to change && to ||.

Fixes: 26fc6c7f02cb ("NFC: st21nfca: Add HCI transaction event support")
Cc: stable@vger.kernel.org
Signed-off-by: Martin Faltesek <mfaltesek@google.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/nfc/st21nfca/se.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/nfc/st21nfca/se.c
+++ b/drivers/nfc/st21nfca/se.c
@@ -319,7 +319,7 @@ int st21nfca_connectivity_event_received
* 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;