ANDROID: NFC: st21nfca: Fix out of bounds kernel access when handling ATR_REQ

Out of bounds kernel accesses in st21nfca's NFC HCI layer
might happen when handling ATR_REQ events if user-specified
atr_req->length is bigger than the buffer size. In
that case memcpy() inside st21nfca_tm_send_atr_res() will
read extra bytes resulting in OOB read from the kernel heap.

Bug: 62679012

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
This commit is contained in:
Suren Baghdasaryan 2017-08-17 10:43:14 -07:00 committed by Amit Pundir
parent 9d30b77414
commit 51d5daea85

View file

@ -217,7 +217,8 @@ static int st21nfca_tm_recv_atr_req(struct nfc_hci_dev *hdev,
atr_req = (struct st21nfca_atr_req *)skb->data;
if (atr_req->length < sizeof(struct st21nfca_atr_req)) {
if (atr_req->length < sizeof(struct st21nfca_atr_req) ||
atr_req->length > skb->len) {
r = -EPROTO;
goto exit;
}