NFC: Fix the number of pipes

According to ETSI TS 102 622 specification chapter 4.4 pipe identifier
is 7 bits long which allows for 128 unique pipe IDs. Because
NFC_HCI_MAX_PIPES is used as the number of pipes supported and not
as the max pipe ID, its value should be 128 instead of 127.

nfc_hci_recv_from_llc extracts pipe ID from packet header using
NFC_HCI_FRAGMENT(0x7F) mask which allows for pipe ID value of 127.
Same happens when NCI_HCP_MSG_GET_PIPE() is being used. With
pipes array having only 127 elements and pipe ID of 127 the OOB memory
access will result.

Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Allen Pais <allen.pais@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/nfc/hci.h b/include/net/nfc/hci.h
index 316694dafa5bae75363e34c035906e2d937c33c6..008f466d1da7ea60c7b46dc4b5133e8ed257c9c3 100644 (file)
--- a/include/net/nfc/hci.h
+++ b/include/net/nfc/hci.h
@@ -87,7 +87,7 @@ struct nfc_hci_pipe {
  * According to specification 102 622 chapter 4.4 Pipes,
  * the pipe identifier is 7 bits long.
  */
-#define NFC_HCI_MAX_PIPES              127
+#define NFC_HCI_MAX_PIPES              128
 struct nfc_hci_init_data {
        u8 gate_count;
        struct nfc_hci_gate gates[NFC_HCI_MAX_CUSTOM_GATES];