[PATCH 4.18 110/158] Bluetooth: hidp: Fix handling of strncpy for hid->name information

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Marcel Holtmann <marcel@holtmann.org>

[ Upstream commit b3cadaa485f0c20add1644a5c877b0765b285c0c ]

This fixes two issues with setting hid->name information.

  CC      net/bluetooth/hidp/core.o
In function ‘hidp_setup_hid’,
    inlined from ‘hidp_session_dev_init’ at net/bluetooth/hidp/core.c:815:9,
    inlined from ‘hidp_session_new’ at net/bluetooth/hidp/core.c:953:8,
    inlined from ‘hidp_connection_add’ at net/bluetooth/hidp/core.c:1366:8:
net/bluetooth/hidp/core.c:778:2: warning: ‘strncpy’ output may be truncated copying 127 bytes from a string of length 127 [-Wstringop-truncation]
  strncpy(hid->name, req->name, sizeof(req->name) - 1);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

  CC      net/bluetooth/hidp/core.o
net/bluetooth/hidp/core.c: In function ‘hidp_setup_hid’:
net/bluetooth/hidp/core.c:778:38: warning: argument to ‘sizeof’ in ‘strncpy’ call is the same expression as the source; did you mean to use the size of the destination? [-Wsizeof-pointer-memaccess]
  strncpy(hid->name, req->name, sizeof(req->name));
                                      ^

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/bluetooth/hidp/core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -775,7 +775,7 @@ static int hidp_setup_hid(struct hidp_se
 	hid->version = req->version;
 	hid->country = req->country;
 
-	strncpy(hid->name, req->name, sizeof(req->name) - 1);
+	strncpy(hid->name, req->name, sizeof(hid->name));
 
 	snprintf(hid->phys, sizeof(hid->phys), "%pMR",
 		 &l2cap_pi(session->ctrl_sock->sk)->chan->src);