[098/126] Bluetooth: RFCOMM - Fix missing msg_namelen update inrfcomm_sock_recvmsg()

From: Steven Rostedt
Date: Tue May 07 2013 - 00:38:48 EST


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

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

From: Mathias Krause <minipli@xxxxxxxxxxxxxx>

[ Upstream commit e11e0455c0d7d3d62276a0c55d9dfbc16779d691 ]

If RFCOMM_DEFER_SETUP is set in the flags, rfcomm_sock_recvmsg() returns
early with 0 without updating the possibly set msg_namelen member. This,
in turn, leads to a 128 byte kernel stack leak in net/socket.c.

Fix this by updating msg_namelen in this case. For all other cases it
will be handled in bt_sock_stream_recvmsg().

Cc: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Cc: Gustavo Padovan <gustavo@xxxxxxxxxxx>
Cc: Johan Hedberg <johan.hedberg@xxxxxxxxx>
Signed-off-by: Mathias Krause <minipli@xxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
net/bluetooth/rfcomm/sock.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 1a17850..3fd0464 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -610,6 +610,7 @@ static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,

if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
rfcomm_dlc_accept(d);
+ msg->msg_namelen = 0;
return 0;
}

--
1.7.10.4


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