Commit 4fbcc1a4 authored by Jordy Zomer's avatar Jordy Zomer Committed by David S. Miller
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nfc: st21nfca: Fix potential buffer overflows in EVT_TRANSACTION 



It appears that there are some buffer overflows in EVT_TRANSACTION.
This happens because the length parameters that are passed to memcpy
come directly from skb->data and are not guarded in any way.

Signed-off-by: default avatarJordy Zomer <jordy@pwning.systems>
Reviewed-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 2a4d75bf

drivers/nfc/st21nfca/se.c

+10 −0
Original line number Diff line number Diff line
@@ -316,6 +316,11 @@ 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))

			return -EINVAL;



		memcpy(transaction->aid, &skb->data[2],

		       transaction->aid_len);
@@ -325,6 +330,11 @@ int st21nfca_connectivity_event_received(struct nfc_hci_dev *hdev, u8 host, 
			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)))

			return -EINVAL;



		memcpy(transaction->params, skb->data +

		       transaction->aid_len + 4, transaction->params_len);