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Subject[PATCH 1/1] NFC: Fix the number of pipes
Date
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.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
include/net/nfc/hci.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/net/nfc/hci.h b/include/net/nfc/hci.h
index 316694dafa5b..008f466d1da7 100644
--- 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];
--
2.18.0.865.gffc8e1a3cd6-goog
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