On Mon, Jun 6, 2022 at 7:57 PM Martin Faltesek <mfaltesek@xxxxxxxxxx> wrote:
>
> Error paths do not free previously allocated memory. Add devm_kfree() to
> those failure paths.
>
> Fixes: 26fc6c7f02cb ("NFC: st21nfca: Add HCI transaction event support")
> Fixes: 4fbcc1a4cb20 ("nfc: st21nfca: Fix potential buffer overflows in EVT_TRANSACTION")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Martin Faltesek <mfaltesek@xxxxxxxxxx>
Reviewed-by: Guenter Roeck <groeck@xxxxxxxxxxxx>
> ---
> drivers/nfc/st21nfca/se.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/nfc/st21nfca/se.c b/drivers/nfc/st21nfca/se.c
> index 9645777f2544..8e1113ce139b 100644
> --- a/drivers/nfc/st21nfca/se.c
> +++ b/drivers/nfc/st21nfca/se.c
> @@ -326,22 +326,29 @@ int st21nfca_connectivity_event_received(struct nfc_hci_dev *hdev, u8 host,
> transaction->aid_len = skb->data[1];
>
> /* Checking if the length of the AID is valid */
> - if (transaction->aid_len > sizeof(transaction->aid))
> + 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)))
> + 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);
> --
> 2.36.1.255.ge46751e96f-goog
>
