NFC: The core part should generate the target index

The target index can be used by userspace to uniquely identify a target
and thus should be kept unique, per NFC adapter. Moreover, some protocols
do not provide a logical index when discovering new targets, so we have to
generate one for them.
For NCI or pn533 to fetch their logical index, we added a logical_idx field
to the target structure.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
index 5a839ceb2e82..b2825aa85f64 100644
--- a/net/nfc/rawsock.c
+++ b/net/nfc/rawsock.c
@@ -92,6 +92,12 @@ static int rawsock_connect(struct socket *sock, struct sockaddr *_addr,
                 goto error;
         }
 
+        if (addr->target_idx > dev->target_idx - 1 ||
+            addr->target_idx < dev->target_idx - dev->n_targets) {
+                rc = -EINVAL;
+                goto error;
+        }
+
         rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol);
         if (rc)
                 goto put_dev;