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kernel os linux

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>

authored by

Suren Baghdasaryan and committed by
David S. Miller
e285d5bf 674d9de0

+1 -1
+1 -1
include/net/nfc/hci.h
··· 87 87 * According to specification 102 622 chapter 4.4 Pipes, 88 88 * the pipe identifier is 7 bits long. 89 89 */ 90 - #define NFC_HCI_MAX_PIPES 127 90 + #define NFC_HCI_MAX_PIPES 128 91 91 struct nfc_hci_init_data { 92 92 u8 gate_count; 93 93 struct nfc_hci_gate gates[NFC_HCI_MAX_CUSTOM_GATES];