From: Jordy Zomer <jordy@pwning.systems> commit 4fbcc1a4cb20fe26ad0225679c536c80f1648221 upstream. 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: Jordy Zomer <jordy@pwning.systems> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Denis Efremov <denis.e.efremov@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/nfc/st21nfca/se.c | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/drivers/nfc/st21nfca/se.c +++ b/drivers/nfc/st21nfca/se.c @@ -330,6 +330,11 @@ int st21nfca_connectivity_event_received 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); @@ -339,6 +344,11 @@ int st21nfca_connectivity_event_received 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);
