[PATCH 3.16 095/134] Bluetooth: Fix user channel for 32bit userspace on 64bit kernel

Ben Hutchings
2017-08-18T13:15:50Z

From: Szymon Janc <szymon.janc@codecoup.pl>

commit ab89f0bdd63a3721f7cd3f064f39fc4ac7ca14d4 upstream.

Running 32bit userspace on 64bit kernel results in MSG_CMSG_COMPAT being
defined as 0x80000000. This results in sendmsg failure if used from 32bit
userspace running on 64bit kernel. Fix this by accounting for MSG_CMSG_COMPAT
in flags check in hci_sock_sendmsg.

Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>
Signed-off-by: Marko Kiiskila <marko@runtime.io>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/bluetooth/hci_sock.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -886,7 +886,8 @@ static int hci_sock_sendmsg(struct kiocb
if (msg->msg_flags & MSG_OOB)
return -EOPNOTSUPP;

- if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_NOSIGNAL|MSG_ERRQUEUE))
+ if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_NOSIGNAL|MSG_ERRQUEUE|
+ MSG_CMSG_COMPAT))
return -EINVAL;

if (len < 4 || len > HCI_MAX_FRAME_SIZE)